Tissue imaging systems, instruments, and methods using fiducial. geometry-based displacement determination

Abstract

Tissue imaging systems, instruments, and methods using fiducial geometry-based displacement determination are provided. One embodiment is a method of determining a fiducial position in a tissue imaging system including: receiving image data representing a fiducial having a predetermined geometry; evaluating a plurality of one-dimensional row segments associated with the image data to generate a plurality of corresponding row-based fiducial position estimates; adjusting one or more of the plurality of row-based fiducial position estimates based on the predetermined geometry; and combining the adjusted fiducial position estimates to determine the fiducial position.

Description

Docket No. CURI-P27WOTISSUE IMAGING SYSTEMS, INSTRUMENTS, AND METHODS USING FIDUCIAL,GEOMETRY-BASED DISPLACEMENT DETERMINATIONCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U. S. Provisional Patent Application No.63 / 776,444, filed March 24, 2025, which is hereby incorporated by reference in its entirety.TECHNIC AL FIELD

[0002] The present disclosure relates generally to tissue analysis systems, and more particularly to imaging systems and methods for determining displacement of fiducial structures in multi-well tissue culture platforms.BACKGROUND

[0003] Engineered tissue models are used in drug screening and disease modeling to evaluate compound effects and disease phenotypes under controlled conditions. In many such models, tissue samples are suspended between supports and generate mechanical contraction over time. Measuring this contractility, by tracking displacement of the tissue supports, provides information that is not accessible through molecular or imaging-based assays alone.

[0004] Multi-well plate formats enable parallel analysis of multiple tissue samples under varying experimental conditions. Scaling contractility measurement to these formats, however, introduces significant technical challenges. Tissue contraction produces small-scale displacements of the ti ssue supports, and resolving these displacements from image data involves precise identification of fiducial features associated with the supports and determination of their positions across image frames. In a multi-well configuration, for example, this precision may be maintained across many wells simultaneously, each with its own optical path, illumination conditions, and sensor alignment. Processing the resulting image data at or near the point of acquisition, rather than offloading it to centralized computing resources, imposes additional computational constraints.

[0005] Image-based techniques for determining position from fiducial features are employed in various technical fields. Multi-well tissue contractility measurement, however, presents a distinct combination of requirements, including, for example, displacement sensitivity across a dense array of parallel optical channels, biology-influenced imaging condition variances between wells, consistent illumination and alignment conditions from well to well, andDocket No. CURI-P27WOcomputational throughput sufficient to keep pace with the well array. Existing approaches do not adequately address this combination,

[0006] Accordingly, there remains a need for improved approaches to determining tissue support displacement in multi-well measurement systems.BRIEF SUMMARY

[0007] Various embodiments of tissue imaging systems, instruments, and methods using fiducial geometry -based displacement determination are provided. One embodiment is a method of determining a fiducial position in a tissue imaging system comprising: receiving image data representing a fiducial having a predetermined geometry; evaluating a plurality of one-dimensional row segments associated with the image data to generate a plurality of corresponding row-based fiducial position estimates; adjusting one or more of the plurality of row-based fiducial position estimates based on the predetermined geometry; and combining the adjusted fiducial position estimates to determine the fiducial position.

[0008] Another embodiment is a tissue imaging system comprising an image sensor array, a plurality of programmable logic devices, multiplexing logic, and a processing module. The image sensor array comprises a plurality of image sensors. Each image sensor is configured to image a respective fiducial of a plurality of fiducials. Each of the plurality of fiducials has a predetermined geometry. The plurality of programmable logic devices is configured to process image data generated by the image sensor array. Each programmable logic device is configured to evaluate one-dimensional row segments of the image data to generate row-based fiducial position data. Multiplexing logic is configured to combine the row-based fiducial position data generated by the plurality of programmable logic devices. The processing module is configured to receive the combined row-based fiducial position data and to determine a fiducial position for the respective fiducial based on the predetermined geometry'.

[0009] Another embodiment of a tissue imaging system comprises: an image module comprising a plurality of image sensors arranged in an image sensor array; an illumination panel comprising a plurality of light sources and defining an opening array comprising a plurality of openings arranged in spatial correspondence with the image sensor array such that each opening of the opening array is aligned with a respective image sensor; and a multi-well tissue suspension cartridge comprising a plurality of wells arranged in a well array, each of the plurality of wells comprising a pair of tissue supports configured to suspend a tissue sample, atDocket No. CURI-P27WOleast one of the pair of tissue supports having a fiducial defining a three-dimensional body having a predetermined geometry, the well array positioned such that each well aligns with a respective opening of the opening array and the respective image sensor.

[0010] A further embodiment is a computer program embodied in a non-transitory computer readable medium and executable by a processor for determining a fiducial position in a tissue imaging system. The computer program comprises logic configured to: receive image data representing a fiducial having a predetermined geometry; evaluate a plurality of onedimensional row segments of the image data to determine corresponding boundary position responses; align the corresponding boundary position responses based on the predetermined geometry; and combine the aligned boundary position responses to determine a fiducial position.

[0011] Yet another embodiment is a tissue imaging instrument comprising: an illumination panel configured to illuminate a multi-well tissue suspension cartridge comprising a plurality of wells arranged in a well array, each of the plurality of wells comprising a pair of tissue supports configured to suspend a tissue sample, at least one of the pair of tissue supports having a fiducial defining a three-dimensional body having a predetermined geometry; an image module comprising a plurality of image sensors arranged in an image sensor array, the image sensor array arranged relative to the well array such that each image sensor corresponds to a respective well and is configured to image the fiducial within that well; and a processor in communication with the image module and the illumination panel, the processor comprising logic configured, for each image sensor to: detect a plurality of boundary positions of the respective fiducial within image data generated by that image sensor, the boundary positions corresponding to the predetermined geometry; and determine displacement of the respective tissue support based on changes in the plurality of boundary positions across image frames generated by that image sensor.

[0012] Another embodiment is a method of analyzing a tissue sample comprising, illuminating a plurality of wells of a multi-well tissue suspension cartridge, each well comprising a pair of tissue supports configured to suspend a tissue sample and at least one fiducial defining a three-dimensional body having a predetermined geometry; capturing image data representing the fiducials over a plurality of image frames; for each fiducial, detecting a plurality of boundary positions of the fiducial within the image data; and determiningDocket No. CURI-P27WOdisplacement of a respective tissue support based on changes in the plurality of boundary positions across the plurality of image frames.

[0013] A further embodiment is a multi-well tissue suspension cartridge comprising: a plurality of wells arranged in a well array; a pair of tissue supports disposed within each well and configured to suspend a tissue sample, at least one of the pair of tissue supports being deflectable along an axis extending between the pair of tissue supports; and at least one fiducial disposed on the at least one deflectable tissue support in each well, the fiducial defining a three-dimensional body having a surface profile that varies in cross-section along the axis according to a predetermined geometric relationship.BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0014] For a more complete understanding of the present disclosure, reference is now made to the following descriptions taken in conjunction with the accompanying figures, in which:

[0015] FIG. 1 is a block diagram illustrating an embodiment of a tissue imaging system.

[0016] FIG. 2 is a diagram illustrating an optical alignment architecture of the tissue imaging system of FIG. 1.

[0017] FIG. 3 illustrates an embodiment of a tissue imaging instrument comprising components of the tissue imaging system of FIG. 1.

[0018] FIG. 4 illustrates an embodiment of a method for analyzing tissue samples using the tissue imaging instrument of FIG. 3.

[0019] FIG. 5 is a bottom plan view of an embodiment of a multi-well tissue suspension cartridge.

[0020] FIG. 6 is a side elevation view of the multi-w7ell tissue suspension cartridge of FIG. 5 in a separated configuration with a casting plate.

[0021] FIG 7 is a cross-sectional view of the multi-well tissue suspension cartridge of FIG. 5 in an assembled configuration with the casting plate.

[0022] FIG. 8 is an enlarged cross-sectional detail view of the tissue supports and fiducials of the multi-well tissue suspension cartridge of FIG. 5 within several wells of the casting plate.

[0023] FIG. 9 is a perspective view of an embodiment of a row bridge flex assembly for use with the multi-well tissue suspension cartridge of FIG. 5.Docket No. CURI-P27WO

[0024] FIG. 10 is a side view of an embodiment of an illumination panel of the tissue imaging instrument of FIG. 3.

[0025] FIG. 11 is a top view of the light source substrate of the illumination panel of FIG. 10.

[0026] FIG. 12 is a top view of the aperture plate of the illumination panel of FIG. 10.

[0027] FIG. 13 is a perspective view of an embodiment of an image module of the tissue imaging instrument of FIG. 3 shown disassembled from the illumination panel.

[0028] FIG. 14 illustrates the image module assembled to the illumination panel.

[0029] FIG 15 is a top view of an alternative embodiment of the illumination panel comprising a planar waveguide.

[0030] FIG. 16 is a side view of the illumination panel of FIG. 15.

[0031] FIG. 17 is a combined block / architecture di agram illustrating an embodiment of the imaging processing system of FIG. 1.

[0032] FIG. ISA - FIG. 18E are schematic representations illustrating an embodiment of row¬ based fiducial position determination using detected boundary positions and a fiducial geometry model.

[0033] FIG. 18F and FIG. 18G are schematic representations illustrating fiducial position estimation from boundary positions with geometry-based adjustment.

[0034] FIG. 19 is a flowchart illustrating an exemplary method of row-based fiducial position determination.

[0035] FIG. 20 is a combined block / architecture diagram of a field-programmable gate array implementation of the row-based fiducialization logic of FIG. 17.DETAILED DESCRIPTION

[0036] The present disclosure provides systems, instruments, cartridges, and methods for analysis of biological tissues, for example determining contractility. Representative examples are provided in the context of tissue contractility; however, this is not limiting. It shall be appreciated that any of the embodiments provided herein may be claimed as systems, instruments, cartridges, and methods for tissue analysis.

[0037] FIG. 1 is a block diagram illustrating an embodiment of a tissue imaging system 100. The tissue imaging system 100 is configured to determine displacement of biological tissueDocket No. CURI-P27WOsamples supported within a multi -well tissue suspension cartridge 102 by capturing image data of fiducials disposed on the tissue supports and processing the captured image data to detect changes in fiducial position over time. As described below in more detail, in certain embodiments, the tissue imaging system 100 may comprise a coordinated system architecture in which the mechanical and spatial configuration of the tissue supports, the geometry of the fiducials, the optical illumination and imaging alignment, and the computational processing are coherently designed in relation to one another to enable efficient and reliable determination of tissue contractility from captured image data.

[0038] As used herein, biological tissue samples may include, for example, any natural or engineered (synthetic) musculoskeletal tissues including skeletal muscle, smooth muscle, cardiac muscle, tendons, and ligaments. Biological tissue samples may also include non-musculoskeletal tissue types, including pulmonary, tracheal, intestinal, hepatic and neuromuscular, and tumors. The foregoing biological samples may be prepared into specimens suitable for analysis in tissue analysis systems as described herein.

[0039] As illustrated in FIG. 1, the tissue imaging system 100 generally comprises a multi¬ well tissue suspension cartridge 102, an image module 104, an illumination panel 106, and an image processing system 108. Elements of the tissue imaging system 100 are, in some embodiments, embodied in a tissue imaging instrument as described below. The multi-well tissue suspension cartridge 102 comprises a plurality of wells arranged in a well array 202 (FIG. 2). As described below in more detail in connection with FIG. 5 - FIG. 8, each well comprises a pair of tissue supports configured to suspend a tissue sample. At least one of the pair of tissue supports includes a fiducial defining a three-dimensional body having a predetermined geometry. In some embodiments, each well comprises a pair of fiducials, with each fiducial disposed on a respective one of the pair of tissue supports. The fiducials provide optically detectable reference features whose positions can be identified across image frames to determine displacement of the tissue supports resulting from contraction or relaxation of the suspended tissue sample.

[0040] The illuminati on panel 106 is configured to illuminate the plurality of wells of the multi-well tissue suspension cartridge 102. In an embodiment, the illumination panel 106 provides spatially and temporally controlled illumination directed toward the wells, enabling consistent optical conditions for imaging the fiducials by the image module 104. The illumination panel 106 defines an opening array 204 comprising a plurality of openingsDocket No. CURI-P27WOarranged in spatial correspondence with the wells, as described in more detail below in connection with FIG, 2. Various structural embodiments of the illumination panel 106 are described below in more detail in connection with FIG. 10 - FIG. 12, FIG 15, and FIG. 16.

[0041] The image processing system 108 is communicatively coupled with the image module 104 and the illumination panel 106. The image processing system 108 is configured to process the captured image data to detect boundary positions of the fiducials and to determine displacement of the tissue supports based on changes in the boundary positions across image frames. As indicated in FIG. 1, the image processing system 108 uses a fiducial geometry model 110 incorporated into the physical design of the fiducials used in the multi-well tissue suspension cartridge 102 The fiducial geometry model 110 represents the expected geometric relationship between boundary positions of a fiducial as defined by the predetermined geometry' of the fiducial.

[0042] Because the fiducials have a predetermined geometry, the boundary positions of each fiducial vary across the image data in accordance with that geometry. For example, in embodiments where the predetermined geometry comprises a spherical surface, the boundary positions detected across different portions of the image data conform to a known geometric relationship that can be expressed in terms of the spherical geometry. The fiducial geometry model 110 captures this geometric relationship, enabling the image processing system 108 to determine fiducial position from detected boundary' positions without requiring computationally intensive full-frame image analysis. In this manner, the predetermined geometry of the fiducials is not merely an incidental physical characteristic but rather an architectural feature of the tissue imaging system 100 that the image processing system 108 is configured to leverage for efficient positional determination.

[0043] In various embodiments, the fiducial geometry model 110 may correspond to an analytical expression, a stored geometric representation, empirical calibration data, a lookup table, or other information defining expected spatial characteristics of the fiducial The fiducial geometry model 110 may define, for example, expected boundary variation across portions of the image data according to the predetermined geometry. Because the boundary positions conform to the fiducial geometry model 110, the image processing system 108 can detect boundary positions independently across different portions of the captured image data and aggregate the detected positions using the known geometric relationship to determine fiducial position. In some embodiments, this geometric aggregation may further enable sub-pixelDocket No. CURI-P27WOpositional determination. The predetermined geometry is not limited to spherical fiducials. The system is applicable to fiducials having other predetermined geometries for which boundary variation can be defined or modeled. FIG. 17 - FIG. 20 illustrate representative embodiments of the structure, logic, architecture, and / operation of the fiducial geometry model 110 as implemented within the image processing system 108, including specific implementations of boundary detection and positional determination based on the predetermined geometry.

[0044] It should be appreciated that the tissue imaging system 100 may further comprise a user interface 112 associated with the image processing system 108, which is configured to receive displacement data from the image processing system 108 and to present the displacement data for visualization, analysis, or further processing. In some embodiments, displacement data may be transmitted to the user interface 112 contemporaneously with capturing the image data, enabling real-time or near-real-time observation of tissue contractility. The user interface 112 may comprise a local display, a remote computing device, an external device, or other local or remote system configured to receive, display, store, or further process the displacement data. In some embodiments, the image processing system 108 generates an output signal representing the displacement data corresponding to one or more wells. Because the image processing system 108 performs fiducial position determination locally, the output signal may be generated without transmitting the image data to an external device.

[0045] It should be appreciated that the architecture of the tissue imaging system 100 reflects a coordinated relationship among the predetermined geometry of the fiducial body structure, the illumination provided by the illumination panel 106, the spatial alignment of the component arrays, and the computational approach implemented by the image processing system 108. The predetermined geometry of the fiducials provides a known geometric framework that the image processing system 108 can leverage through the fiducial geometry model 110 to reduce computational complexity. The illumination panel 106 and the optical alignment of the component arrays, described in more detail in connection with FIG. 2, provide consistent and uniform imaging conditions across the well array 202 such that the fiducial boundary positions detected in the image data reliably conform to the fiducial geometry model 110. The image processing system 108 is configured to leverage the consistent boundary behavior resulting from the predetermined geometry. In this manner, the mechanical, optical, and computationalDocket No. CURI-P27WOelements of the tissue imaging system 100 may be designed in certain embodiments to operate in concert, with each element supporting the efficiency and reliability of the others. Specific implementations of the computational processing provided by image processing system 108, including an edge processing architecture for geometry-based fiducial localization, are described in more detail in connection with FIG. 17 - FIG. 20.

[0046] FIG. 2 illustrates an optical alignment architecture 200 of the tissue imaging system 100. The optical alignment architecture 200 describes the spatial relationship between three component arrays that define the optical imaging geometry of the system: (1) a well array 202 defined by the multi-well tissue suspension cartridge 102; (2) an opening array 204 defined by the illumination panel 106; and (3) and an image sensor array 206 defined by the image module 104

[0047] As illustrated in FIG. 2, the well array 202 comprises the plurality of wells of the multi-well tissue suspension cartridge 102. Each well contains a plurality of tissue supports (e.g, posts, beams, flexures) configured to suspend a tissue sample therebetween, with at least, one tissue support including a fiducial having the predetermined geometry. The opening array 204 comprises a plurality of openings defined by the illumination panel 106 and arranged in spatial correspondence with the well array 202. The image sensor array 206 comprises the plurality of image sensors of the image module 104, arranged in spatial correspondence with the well array 202 and the opening array 204.

[0048] The three arrays are arranged such that each well of the well array 202 aligns spatially and optically with a respective opening of the opening array 204 and a respective image sensor of the image sensor array 206. This alignment defines a plurality of optical channels 208 extending longitudinally through the tissue imaging system 100. Each optical channel 208 corresponds to a respective well and establishes a dedicated optical path from the illumination panel 106, through the respective opening, through the respective well, and to the respective image sensor. In the illustrated embodiment, four representative optical channels 208a, 208b, 208c, and 208d are shown, although it should be appreciated that the optical alignment architecture 200 may define any number of optical channels 208 corresponding up to the number of wells in the well array 202. In some embodiments, the numbers of wells, openings, and image arrays are equal. Advantageously, such configurations may maximize parallelization as all wells can be illuminated and imaged contemporaneously. In other embodiments, the multi-well tissue suspension cartridge 102 has a greater number of wells thanDocket No. CURI-P27WOa number of openings of the opening array 204 and / or a number of image sensors of the image sensor array 206, Restated, such embodiments are configured to have fewer complete optical channels than the number of wells, e.g., only 8 or 16 wells are imaged at a given time.

[0049] As described below in more detail in connection with FIG. 10 - FIG. 12, in some embodiments, light sources 210 of the illumination panel 106 are arranged circumferentially around the openings of the opening array 204. The light sources 210 are configured to provide uniform illumination to the plurality of wells. Illumination may be directed toward the multiwell tissue suspension cartridge 102, with reflected light from each of the fiducials in the well array 202 then propagating through the optical channels 208 via the openings in the illumination panel 106 and terminating at the respective image sensor. In some embodiments, one or more of the light sources 210 comprises a light emitting diode configured to emit light at a wavelength of 300 nm to about 900 nm, although one of ordinary skill in the art will appreciate that the wavelength or other parameters associated with the light sources 210 may be configured based on factors including, for example, the optical contrast between the fiduci l 510 (see FIG. 8)and the surrounding structure, tissue or media, the spectral sensitivity of the image sensors 1302, and the optical properties of the materials within the well 502.

[0050] The optical alignment architecture 200 enables each well to be independently illuminated and imaged under consistent optical conditions. Because each optical channel 208 provides a dedicated path between a respective well, opening, and image sensor, the imaging conditions across wells are uniform. This uniformity has a direct relationship to the computational architecture of the image processing system 108. Spatially uniform illumination across the well array 202 produces image data in which fiducial boundary positions are reliably detectable and in which the detected boundary positions conform consistently to the fiducial geometry model 110 (FIG. 1). Accordingly, the optical alignment architecture 200 may provide a consistent imaging foundation upon which certain embodiments of the image processing system 108 may advantageously implement a geometry-based processing approach. Variations in illumination intensity, angle, or uniformity across wells could introduce inconsistencies in detected boundary positions that would not conform to the fiducial geometry model 110, potentially degrading the efficiency and accuracy of the positional determination. The optical alignment architecture 200 may be designed to minimize such variations and to support reliable geometry-based processing across the entire well array 202.Docket No. CURI-P27WO

[0051] It should be appreciated that the spatial correspondence among the well array 202, the opening array 204, and the image sensor array 206 is an architectural feature of the tissue imaging system 100 that enables parallel, per-well imaging with consistent optical geometry. The alignment of the three arrays and the resulting optical channels 208 allow the image processing system 108 to process image data from individual wells independently while relying on the consistent relationship between fiducial geometry and detected boundary positions. In this manner, the optical alignment, architecture 200, together with the predetermined geometry of the fiducials and the fiducial geometry model 110, provides the physical and geometric basis for the computational processing described in more detail in connection with FIG. 17 - FIG. 20.

[0052] FIG. 3 illustrates an embodiment of a tissue imaging instrument 300 comprising a stacked assembly of mechanical, optical, and electronic components. The tissue imaging instrument 300 houses components of the tissue imaging system 100 in a physical arrangement configured to maintain the optical alignment architecture 200 described above in connection with FIG. 2.

[0053] As illustrated in FIG. 3, the tissue imaging instrument 300 comprises, in a stacked configuration from top to bottom: a maintenance plate 304, the illumination panel 106, and the image module 104. In the illustrated embodiment, a stimulation module 302 is disposed above the multi-well tissue suspension cartridge 102, and the multi -well tissue suspension cartridge 102 is positioned on the maintenance plate 304. The stacked configuration positions the multi¬ well tissue suspension cartridge 102 above the illumination panel 106 and the image module 104, establishing the longitudinal optical channels 208 (FIG. 2) through which illumination and image capture occur. It should be appreciated that the multi-well tissue suspension cartridge 102 and the stimulation module 302 are separable from the tissue imaging instrument 300 and may be provided independently of the instrument. Furthermore, the maintenance plate 304 may form part of the multi-well tissue suspension cartridge 102.

[0054] The stimulation module 302 is disposed above the multi-well tissue suspension cartridge 102. The stimulation module 302 may be configured to provide electrical, optical, or other stimulation to the tissue samples suspended within the wells of the multi-well tissue suspension cartridge 102, e.g., via electrodes extending into the well. In some embodiments, the stimulation module 302 provides electrical pacing signals to promote contractile activity in the tissue samples.Docket No. CURI-P27WO

[0055] The maintenance plate 304 is disposed between the multi-well tissue suspension cartridge 102 and the illumination panel 106, and in some embodiments, forms part of the multi-well tissue suspension cartridge 102. The maintenance plate 304 has a plurality of transparent-bottom wells arranged in a Society For Biomolecular Screening (SBS) - compliant format, and is configured to receive and support the multi -well tissue suspension cartridge 102 following tissue casting. As described below in connection with FIG. 5 - FIG. 8, tissue samples are cast onto the pair of tissue supports 504 while the top portion cartridge frame 516 is mated with the casting plate 602. After casting, the top portion cartridge frame 516 is separated from the casting plate 602 and coupled to the maintenance plate 304. The maintenance plate 304 with the coupled multi -well tissue suspension cartridge 102 is then positioned within the tissue imaging instrument 300. The maintenance plate 304 positions the multi-well tissue suspension cartridge 102 in alignment with the illumination panel 106 and the image module 104, maintaining the spatial correspondence among the well array 202, the opening array 204, and the image sensor array 206 described above in connection with FIG. 2. Representative maintenance plates comprise, for example, a Society For Biomolecular Screening (SBS) - compatible layout, for example a 24, 48, 96 well layout.

[0056] The illumination panel 106 is positioned below the maintenance plate 304 and above the image module 104. This arrangement enables illumination to be directed upward toward the wells of the multi -well tissue suspension cartridge 102, with reflected light from the fiducials propagating downward through the openings of the opening array 204 to the image sensors of the image sensor array 206. Various structural embodiments of the illumination panel 106, including light source arrangements and thermal management features, are described in more detail in connection with FIG. 10 - FIG. 12, FIG. 15 and FIG. 16.

[0057] The image module 104 is positioned at the bottom of the stacked configuration. The image module 104 comprises the plurality of image sensors arranged in the image sensor array 206, each image sensor aligned with a respective opening and a respective well to form the optical channels 208. Various structural details of the image module 104 are described below in connection with FIG 13 and FIG. 14.

[0058] It should be appreciated that the stacked configuration of the tissue imaging instrument 300 is designed to maintain the optical alignment architecture 200 with suitable illumination parameters while allowing the multi-well tissue suspension cartridge 102 to be positioned within and removed from the instrument. The multi-well tissue suspension cartridge 102 isDocket No. CURI-P27WOcoupled to the maintenance plate 304 following separation from the casting plate 602 and placed upon the instrument as an assembly. The mechanical arrangement of the tissue imaging instrument 300 preserves the spatial correspondence among the component arrays that enables the consistent optical conditions and geometry-based computational processing described above. Detailed structural descriptions of embodiments of the individual components illustrated in FIG. 3 are provided in connection with FIG. 5 - FIG. 16.

[0059] Having described the system architecture (FIG. 1), optical alignment (FIG. 2), and physical instrument configuration (FIG. 3) of the tissue imaging system 100, an exemplary operational method will now be described with reference to FIG. 4. The method illustrates how the architectural elements described above operate together during analysis of tissue samples.

[0060] FIG. 4 illustrates an exemplary embodiment of a method 400 for analyzing tissue samples in the tissue imaging instrument 300 (FIG. 3). It should be appreciated that each of the blocks, including functional, operational, and any architectural aspects of each, may be implemented via one or more of the system and / or instrument components described herein.

[0061] At block 402, a multi-well tissue suspension cartridge 102 is positioned within the tissue imaging instrument 300. The multi-well tissue suspension cartridge 102 includes a plurality of wells arranged in a well array 202 (FIG. 2). Each well comprises a pair of tissue supports 504 (see FIG. 5) configured to suspend a tissue sample. At least one of the tissue supports may include a fiducial 510 (see FIG. 8) defining a three-dimensional body having a predetermined geometry. In some embodiments, the multi-well tissue suspension cartridge 102 may be aligned within the tissue imaging instrument 300 such that each fiducial corresponds spatial ly to a respective image sensor in the image sensor array 206 provided by the image module 104 and a respective opening in the opening array 204 provided by the illumination panel 106.

[0062] At block 404, the plurality of wells of the multi-well tissue suspension cartridge 102 are illuminated. Illumination may be provided by an illumination panel 106 configured to spatially and temporally illuminate the wells. Various embodiments of the illumination panel 106 are described below in more detail in connection with FIG. 10 - FIG. 12, FIG. 15, and FIG.16. In an embodiment, illumination may be provided through direct illumination toward the multi -well tissue suspension cartridge 102 with reflected light from each of the fiducials in the well array 202 then propagating through the controlled optical alignment architecture 200 viaDocket No. CURI-P27WOoptical channels 208 extending between each well through the openings in the illumination panel and terminating at the respective image sensor (FIG, 2).

[0063] At block 406, image data representing the fiducials disposed within the wells is captured over a plurality of image frames in the time domain for each well using the image module 104 providing the image sensor array 206 comprising the plurality of image sensors Each image sensor corresponds to a respective well such that movement of a fiducial associated with a tissue support can be observed across image frames generated by that image sensor. In some embodiments, each image sensor generates image data comprising pixel intensity values arranged in a two-dimensional array representing the imaged fiducial within the corresponding well

[0064] At block 408, a plurality of boundary positions of the fiducials are identified within the captured image data. The boundary positions correspond to transitions between optical regions associated with the fiducial and the surrounding background, as defined by the predetermined geometry of the fiducial. In some embodiments, identifying boundary positions comprises evaluating a plurality of one-dimensional row segments of the image data in which each row segment corresponds to a horizontal subset of pixel intensity values within the image data. Each row segment may be evaluated independently to generate a row-based fiducial position estimate corresponding to a detected boundary position within that row segment. In some embodiments, evaluation of a row segment comprises applying a one-dimensional evaluation function, such as a convolution kernel, across sequential pixel values within the row segment to detect a transition in pixel intensity corresponding to a fiducial boundary. A representative embodiment of boundary position identification using row-based evaluation is described in more detail in connection with FIG. 18A - FIG. 18G.

[0065] At block 410, displacement of respective tissue supports is determined based on changes in the plurality of boundary positions across the plurality of image frames. In some embodiments, determining displacement comprises adjusting one or more of the row-based fiducial position estimates based on the predetermined geometry. Because the boundary position observed within a given row segment varies as a function of the position of that row segment relative to the fiducial, the row-based fiducial position estimates may be shifted or transformed according to an expected boundary variation defined by the predetermined geometry, as represented in the fiducial geometry model 110 (FIG. 1). The adjusted fiducial position estimates may then be combined by aggregating the adjusted estimates across theDocket No. CURI-P27WOplurality of row segments to generate a combined response from which a fiducial position is determined. In some embodiments, the fiducial position may be determined by identifying a peak of the combined response, and the peak may be interpolated to determine a sub-pixel fiducial position. Because a fiducial center is determinable from the boundary positions, the image processing system 108 may determine the fiducial center and track changes in the fiducial center across the plurality of image frames to measure displacement of the respective tissue support resulting from contraction or relaxation of the suspended tissue sample, A representative embodiment of geometry-based adjustment, aggregation, and positional determination is described in more detail in connection with FIG. 18D - FIG. 18G.

[0066] At block 412, displacement data representing contractility of the tissue samples is generated. The displacement data may be transmitted to a user interface or other local or remote system for visualization, analysis, additional processing, or storage. In some embodiments, displacement data may be provided contemporaneously with image acquisition. The displacement data may be analyzed in connection with known mechanical properties of a flexible post assembly 514 (see FIG. 8) to determine a contraction force exerted by the tissue sample, e g., based on beam theory For example, the flexible post assembly may be characterized by a known stiffness, and the measured displacement of the fiducial 510 may be used with the known stiffness to calculate the contractile force of the tissue. In this manner, the tissue imaging system 100 may generate both displacement data and force data from the captured image data.

[0067] It should be appreciated that, in certain embodiments, prior to positioning the cartridge within the tissue imaging instrument 300, a tissue sample is first cast onto the pair of tissue supports within each well of the cartridge, and the top portion cartridge frame 516 is separated from the casting plate 602 and coupled to the maintenance plate 304 as described above in connection with FIG. 3. Additional aspects and techniques for detecting boundary positions and determining fiducial positions based on the predetermined geometry of the fiducials are described in more detail with reference to FIG. 17 - FIG. 20, which illustrate representative embodiments of the structure, logic, architecture, and / or operation of the fiducial geometry model 110 as implemented within the image processing system 108.

[0068] Having described the general system architecture, optical alignment, instrument configuration, and operational method of the tissue imaging system 100, detailed structural descriptions of certain embodiments of the individual components of the tissue imagingDocket No. CURI-P27WOinstrument 300 will now be provided. FIG. 5 - FIG. 16 describe structural aspects of embodiments of the multi-well tissue suspension cartridge 102, the illumination panel 106, and the image module 104, including the tissue support, fiducial, and well configurations that implement the predetermined geometry and optical alignment architecture described above.

[0069] FIG. 5 - FIG. 8 show various views of a representative multi-well tissue suspension cartridge 102 as described above.

[0070] FIG. 5 is a bottom plan view of an embodiment of the multi-well tissue suspension cartridge 102. The multi-well tissue suspension cartridge 102 comprises a lattice structure 506 defining a plurality of wells 502 arranged in a well array 202. The lattice structure 506 comprises a support frame from which a plurality of lattice cross-members 508 extend. The lattice cross-members 508 define openings corresponding to the wells 502. In the illustrated embodiment, the wells 502 are arranged in a grid configuration corresponding to a multi-well plate format of a maintenance plate and casting plate configured for coupling with the lattice structure 506. Each well 502 is associated with and comprises a pair of tissue supports 504, each pair comprising a rigid post assembly 512 and a flexible post assembly 514 coupled to and extending from the lattice structure 506 and configured to suspend a tissue sample therebetween (e.g., as shown in the image data of FIG. 18 A). At least one of the tissue supports 802 (see FIG. 8) of each pair of tissue supports 504 (at least the flexible post assembly 514) includes a fiducial 510 projecting from a distal end thereof and defining a three-dimensional body having a predetermined geometry.

[0071] As illustrated in FIG. 5, the multi-well tissue suspension cartridge 102 comprises a top portion cartridge frame 516 including the lattice structure 506, which cartridge frame 516 is configured to couple with (e.g., sit atop) optional casting plate 602 (shown in FIG 6). The top portion cartridge frame 516 is disposed over the wells 502 and supports the pair of tissue supports 504 such that the tissue supports 802 extend from the lattice structure 506 into the respective wells 502. In the illustrated embodiment, each well 502 of the lattice structure 506 comprises a rigid post assembly 512 and a flexible post assembly 514 coupled thereto, with at least the flexible post assembly 514 having a fiducial 510 extending from a distal end thereof. In some embodiments, both the rigid post assembly 512 and the flexible post assembly 514 include respective fiducials 510.

[0072] FIG. 6 is a side view of the multi-well tissue suspension cartridge 102 with the top portion cartridge frame 516 separated from the casting plate casting plate 602. As illustrated,Docket No. CURI-P27WOthe top portion cartridge frame 516 may comprise a lid member disposed over the wells 502 of the casting plate 602. When separated from the casting plate casting plate 602, the tissue supports 802 and fiducials 510 are visible extending from the underside of the top portion cartridge frame 516. The top portion cartridge frame 516 comprises the lattice structure 506 from which a plurality of rigid post assemblies 512 and flexible post assemblies 514 extend. The lattice structure 506 positions the rigid post assemblies 512 and flexible post assemblies 514 in spatial correspondence with the wells 502 of the casting plate 602, The top portion cartridge frame 516 further provides support positions for receiving one or more flexible post assemblies, each of which carries a flexure 810 as described below in connection with FIG. 8. The casting plate 602 defines the well geometry for each well 502, including the cavity shape into which a tissue sample may be cast onto the pair of tissue supports 504.

[0073] As described above in connection with FIG. 3, biological tissue samples are cast onto the pair of tissue supports 504 while the top portion cartridge frame 516 is mated with the casting plate 602. The casting plate 602 defines a well cavity for each well 502 of the lattice structure 506 into which a tissue sample may be cast onto the pair of tissue supports 504. In some embodiments, the casting plate 602 comprises at least one fiducial recess 808 formed in a bottom surface of each well cavity. The fiducial recess 808 is configured to receive a distal end of the respective flexible post assembly 514 and rigid post assembly 512 and to prevent biological tissue or media from occluding the fiducials 510 during the casting process, which would reduce the fidelity of the algorithm edge detection process described herein. Because the fiducials 510 are seated within the fiducial recesses 808 during the casting process, the fiducials 510 are not enveloped by the casting media and the tissue samples do not form around the fiducials 510. In this manner, the fiducials 510 remain unobscured by the cast tissue samples, which facilitates clear imaging by the image sensor array 206 during use. After casting, the top portion cartridge frame 516 is separated from the casting plate 602 and coupled to the maintenance plate 304 prior to placement within the tissue imaging instrument 300. The maintenance plate 304 has transparent wells that enable imaging of the tissues therein

[0074] FIG 7 is a cross-sectional view of the multi-well tissue suspension cartridge 102 with the top portion cartridge frame 516 mated with the casting plate 602. The cross-section is taken along a plane intersecting a row of wells 502 as shown in FIG. 5, illustrating the repeating arrangement of tissue support structures across the well array 202. As illustrated, the top portion cartridge frame 516 seats upon the casting plate 602, with the pairs of tissueDocket No. CURI-P27WOsupports 504 extending downward from the top portion cartridge frame 516 into the well cavities defined by the casting plate 602. The cross-hatched upper region corresponds to the casting plate 602, and the cross-hatched internal structures correspond to the top portion cartridge frame 516 and the flexible and rigid tissue support structures extending therefrom.

[0075] As illustrated, the top portion cartridge frame 516 comprises the lattice structure 506 including a plurality of lattice cross-members 508 from which the rigid post assemblies 512 extend integrally downward into the well cavities of the casting plate 602. The lattice structure 506 spaces the rigid post assemblies 512 in registration with the wells 502 such that each well 502 of the lattice structure 506 receives one rigid post assembly 512. A flexible post assembly 514 is received within the top portion cartridge frame 516, each flexible post assembly 514 extending downward into a respective well 502 alongside a corresponding rigid post assembly 512 to form the pair of tissue supports 504. In the assembled configuration with the casting plate 602, each pair of tissue supports 504 is positioned within a respective well cavity of the casting plate 602 with the fiducials 510 disposed at the free ends of the tissue supports, spaced apart along an axis extending between the rigid post assembly 512 and the flexible post assembly 514.

[0076] Although FIG 7 shows the cartridge frame 516 coupled with the casting plate 602, it should be appreciated that the casting plate 602 is replaced with a maintenance plate prior to imaging, and the assembled configuration of FIG. 7 corresponds to the multi-well tissue suspension cartridge 102 as positioned within the tissue imaging instrument 300 (FIG. 3) on such a maintenance plate, with the fiducials 510 disposed within the optical path of the optical channels 208 defined by the optical alignment architecture 200 (FIG. 2).

[0077] FIG. 8 is an enlarged cross-sectional detail view' illustrating structural features of the tissue supports 802 and fiducials 510 of the multi-well tissue suspension cartridge 102 within two adjacent wells 502 of the casting plate 602. The cross-hatched region at the bottom of FIG.8 corresponds to the casting plate 602, which defines the well cavities. The remaining cross-hatched structures correspond to the top portion cartridge frame 516, the lattice structure 506 thereof, and the tissue support structures extending therefrom. The enlarged view reveals the structural differentiation between the rigid post assembly 512 and the flexible post assembly 514, the regional geometry of each tissue support 802, and the spatial relationship of the tissue support components within the well cavity.Docket No. CURI-P27WO0078] Each well 502 of the cartridge frame 516 comprises a pair of tissue supports 504 formed by a corresponding rigid post assembly 512 and a flexible post assembly 514. Each of the rigid post assembly 512 and the flexible post assembly 514 comprises a post or beam, a tissue localizer portion 806, and optionally a fiducial 510. The rigid post assemblies 512 and the flexible post assemblies 514 have different structural profiles configured to provide different mechanical responses to tissue contraction. In the illustrated embodiment, each of the rigid post assemblies 512 couples with the top portion of the cartridge frame 516 and extends from the lattice structure toward the casting plate 602 or the maintenance plate. The rigid post assemblies 512 may be a separate component received within, or affixed to, and supported by the top portion cartridge frame 516 in a manner similar to the flexible post assembly 514.

[0079] Each rigid post assembly 512 comprises a rigid post 812, the tissue localizer portion 806 attached to a distal end of the rigid post 812, and optionally a fiducial 510 extending from a distal end of the tissue localizer portion 806 (opposite the rigid post rigid post 812). The rigid post 812 comprises a relatively rigid elongate beam or post having a higher stiffness or Young's modulus relative to the flexure 810 of the flexible post assembly 514.

[0080] As illustrated, the rigid post 812 of the rigid post assembly 512 has a relatively stiff cross-sectional profile, providing sufficient stiffness to remain stationary under the contractile forces exerted by the tissue sample In some embodiments, the cross section of the rigid post rigid post 812 is circular, rectangular, a structural section, or other shape providing sufficient stiffness to prevent deformation toward the flexible post assembly 514 when a tissue contracts therebetween. In this manner, the rigid post assembly 512 serves as a fixed reference against which displacement of the opposing flexible post assembly 514 can be measured.

[0081] Each flexible post assembly 514 comprises a flexure 810, the tissue localizer portion 806 attached to a distal end of the flexure 810, and a fiducial 510 extending from a distal end of the tissue localizer portion 806 (opposite the flexure 810). The flexure 810 comprises a relatively flexible post, beam, shim, or other elongate structure having a lower stiffness or Young's modulus relative to the rigid post rigid post 812. A fixed end of the flexure 810 is coupled with the lattice structure 506, and a distal end of the flexure 810 is coupled to the tissue localizer portion 806.

[0082] The term “rigid post” and “flexure” may be defined absolutely and / or relatively. For example, in some embodiments, each rigid post (e.g., rigid post 812) has a greater force-to- displacement relationship, e.g., at one point along the length of the post (e.g., a greater stiffnessDocket No. CURI-P27WOat the distal end) and / or a different Young's modulus than the flexure (e.g., flexure 810) in the same well. In some examples, the foregoing relationship (e.g., between the stiffness of the rigid post and the flexure) may have a ratio of 1x - 1,000x, e.g., about 1x to about 500x, about 5x to about 500x, or about 10x to about 300x. In absolute terms, by way of example, not limitation, in some embodiments, each rigid post has a stiffness of about 1,000 N / m to about 10,000 N / m, for example about 10N / m to about 30N / m (e.g., about 12N / m or 24N / m). In some embodiments, each flexure has a stiffness of about O.lN / m to about 5N / m, e.g., about.2N / m.

[0083] As illustrated in FIG. 8, the flexure 810 has a slender cross-sectional profile providing a lower bending stiffness such that the flexible post assembly 514 is configured to deflect toward the rigid post assembly 512 in response to contractile forces exerted by the tissue sample suspended between the pair of tissue supports 504. In this regard, the flexible post assembly 514 serves as a flexible support on which the fiducial 510 is disposed, such that deflection of the flexure 810 produces a corresponding displacement of the fiducial 510 In some embodiments, the flexure 810 comprises a thermoplastic or other non-elastomeric material. A non-elastomeric flexure material may reduce absorption of molecular compounds from the tissue sample or surrounding media relative to an elastomeric material, and may further reduce shape memory effects that could influence the resting position of the flexure 810 over time.

[0084] Each tissue support 802, whether comprising the rigid post assembly 512 or the flexible post assembly 514, comprises a tissue localizer portion 806. The tissue localizer portion 806 defines a narrowed waist or center region of the tissue support 802 having a reduced cross-sectional width relative to adjacent portions of the tissue support 802 above and below the tissue localizer portion 806. As illustrated in FIG. 8, the tissue localizer portion 806 has an hourglass-shaped profile in which the cross-sectional width tapers inward to a minimum width at the waist and then tapers outward toward the fiducial 510. This narrowed center region is configured guide or localize the attachment of the tissue sample at a defined location along the tissue support 802 during casting, as the tissue conforms around the reduced-width region and is thereby localized to the middle region between the pair of tissue supports 504.

[0085] In some embodiments, the tissue localizer portion 806 and the fiducial 510 are formed of materials that optically contrast. For example, in some embodiments, the tissue localizer portion 806 is formed of a dark polymeric materials and the fiducial 510 is a light-colored body, for example zirconium oxide sphere. Because the tissue localizer portion 806 has aDocket No. CURI-P27WOgreater cross-sectional width relative to the fiducial 510, the transition between the tissue localizer portion 806 and the fiducial 510 creates a region of optical contrast that may facilitate boundary discrimination during image-based fiducial detection as described below in connection with FIG. 17 - FIG. 20 (see, e.g., FIG. 18A).

[0086] As further illustrated in FIG. 8, a neck 804 may provide a structural transition between the tissue localizer portion 806 and the fiducial 510. The neck 804 defines a transitional region in which the cross-sectional profile of the tissue support 802 changes from the narrowed geometry of the tissue localizer portion 806 to the three-dimensional body of the fiducial 510. In the illustrated embodiment, the neck 804 tapers outward from the tissue localizer portion 806 and merges into the surface of the fiducial 510.

[0087] The fiducial 510 is disposed at the distal or free end of each tissue support 802, defining a three-dimensional body having a predetermined geometry. In the illustrated embodiment, the fiducial 510 comprises a spherical body. As described above generally and in more detail below in connection with FIG. 17 - FIG. 20, a spherical fiducial is symmetric about a central axis and accordingly provides a uniform boundary profile regardless of the deflection angle of the tissue support, allowing the fiducial geometry model 110 to remain valid as the flexible post assembly 514 deflects under tissue contraction. The spherical shape of the fiducial 510 provides a detectable boundary between a first optical region and a second optical region having different optical characteristics on opposite sides of the fiducial 510. In some embodiments, the fiducial 510 comprises a high-contrast material such that the boundary between the fiducial surface and the surrounding background is optically detectable by the image sensors of the image sensor array 206 (FIG. 2). The fiducial 510 may be integrally formed with the tissue support 802.

[0088] In some embodiments, the fiducial 510 comprises a light-colored spherical body, for example a zirconium oxide sphere. A light-colored fiducial may reduce specular glare from the illumination panel 106 such that pixel intensity values across the fiducial surface are consistent, facilitating boundary detection. Additionally, signal-to-noise ratio of the image sensor is proportional to the square root of the number of photons received. Accordingly, a brighter fiducial surface increases the number of photons reaching the image sensor, which may improve the signal-to-noise ratio of the fiducial detection performed by the image processing system 108. The tissue localizer portion 806 may comprise a dark-colored material, for example a dark-colored polymer, to provide stark visual contrast with the fiducial 510. In someDocket No. CURI-P27WOembodiments, the tissue localizer portion 806 may have a greater maximum cross-sectional width than the fiducial 510 such that, when imaged from below by the image sensor array 206, the fiducial 510 is bounded by the tissue localizer portion 806 and optically isolated from other structures within the well 502.

[0089] The surface profile of the fiducial 510 may vary in cross-section along the axis extending between the pair of tissue supports 504 according to a predetermined geometric relationship. For example, in embodiments where the fiducial 510 is spherical, the crosssection varies continuously along the axis, and the predetermined geometric relationship may be expressed as a radial distance function along the axis. A plurality of parallel cross-sections of the three-dimensional body perpendicular to the axis define boundary positions that conform to the predetermined geometric relationship. In this regard, as described below in more detail in connection with FIG. 18A - FIG. 18G, each one-dimensional row segment 1808 evaluated by the image processing system 108 corresponds to a parallel cross-section of the fiducial 510 perpendicular to the axis. Because the boundary positions defined by these cross-sections vary according to the predetermined geometric relationship, the fiducial geometry model 110 (FIG.1) can represent the expected boundary variation across row segments and enable a geometrybased adjustment (FIG. 18D and FIG. 18E). In this manner, the physical cross-sectional profile of the fiducial 510 provides a structural basis for the row-based fiducial position determination performed by the image processing system 108.

[0090] In some embodiments, at least one of the pair of tissue supports 504 comprises an epoxy-based material. In certain embodiments, at least one of the pair of tissue supports 504 comprises a silica material configured to reduce hydrophobic recovery of a surface of the tissue support, which may improve tissue adhesion and retention on the tissue support during tissue casting and culture.

[0091] In some embodiments, the tissue localizer portion 806 defines a body having a waist, a skirt, and a fiducial attachment feature. The waist corresponds to a smallest-diameter region of the body of the tissue localizer portion 806. The skirt is disposed at a bottom end of the body and radially projects around the fiducial 510 when viewed by the image module 104, creating an optically contrasting backdrop against which the fiducial 510 is imaged. The fiducial attachment feature comprises a seat, recess, depression, or other structural feature formed in the tissue localizer portion 806 that localizes the fiducial 510 relative to the tissue localizer portionDocket No. CURI-P27WO806 for consistent imaging. In some embodiments, the fiducial 510 is attached to or seated within the fiducial attachment feature by adhesive, friction fit, or co-molding.

[0092] The tissue localizer portion 806 may be attached to the distal end of the flexure 810 or the rigid post rigid post 812 by various attachment means, including adhesive bonding, friction fit, co-molding, or integral formation. In some embodiments, the tissue localizer portion 806 is integrally formed with the flexure 810 or the rigid post rigid post 812 as a unitary component.

[0093] It should be appreciated that the structural arrangement of the rigid post assemblies 512 and flexible post assemblies 514 relative to the lattice structure 506 may vary among embodiments, and the configurations described in connection with FIG. 5 through FIG. 9 are representative of a broader range of structural variations.

[0094] In some embodiments, the flexible post assemblies 514 and / or the rigid post assemblies 512 are attached to a top side of the lattice structure 506 via mechanical and / or adhesive coupling or friction fit. In other embodiments, the flexible post assemblies 514 and / or the rigid post assemblies 512 are attached to a bottom side of the lattice structure 506 via mechanical and / or adhesive coupling or friction fit. In still other embodiments, the flexible post assemblies 514 and / or the rigid post assemblies 512 are integrally formed with the lattice structure 506.

[0095] FIG. 9 illustrates an embodiment of the row bridge flex assembly 900 for use with the multi-well tissue suspension cartridge 102. The row bridge flex assembly 900 comprises the bridge rail 902 extending laterally across a plurality of wells 502 and a plurality of branching arms 904 extending from the bridge rail 902. Each branching arm 904 terminates at a respective flexure 810. Each flexure 810 extends to the tissue localizer portion 806 at a distal end thereof, and the fiducial 510 is disposed at a distal end of the tissue localizer portion 806. In the illustrated embodiment, the bridge rail 902 and branching arms 904 position the flexures 810 in spatial correspondence with the wells 502 of the lattice structure 506 such that each flexible post assembly 514 extends into a respective well 502.

[0096] The bridge rail 902 may be formed of a rigid material and the flexures 810 may be formed of a material and shape having reduced stiffness than the bridge rail 902, such that each flexure 810 is configured to deflect relative to the bridge rail 902 in response to contractile forces exerted by a tissue sample. In some embodiments, the row bridge flex assembly 900 is integrally formed as a unitary element. In other embodiments, the flexures 810 are separatelyDocket No. CURI-P27WOformed and attached to the branching arms 904 by adhesive, friction fit, co-molding, or other attachment means.

[0097] It shall be appreciated, that the rigid post assemblies 512 may also be connected across wells by a similar bridge rail. Advantageously, such bridging structures facilitate manufacturing and ensure consistent placement of the pairs of tissue supports 504 within each well.

[0098] In some embodiments, a bridge, such as the bridge rail 902, connects a plurality of flexible post assemblies 514 across wells 502. In other embodiments, a bridge connects a plurality of rigid post assemblies 512 across wells 502. In still other embodiments, a bridge connects both flexible post assemblies 514 and rigid post assemblies 512 across wells 502, such that pairs of opposing post assemblies are carried on a common bridge structure. In yet other embodiments, no bridge is provided, and each flexible post assembly 514 and each rigid post assembly 512 is individually attached to or integrally formed with the lattice structure 506.

[0099] In some embodiments, the flexible post assembly 514 and the rigid post assembly 512 for each well 502 are coupled to each other by a post module comprising a bridge that fixes the relative spacing between the rigid post assembly 512 and the flexible post assembly 514 within the well 502. The post module may be attached to the top side or the bottom side of the lattice structure 506 as a modular unit.

[0100] In various embodiments, the wells 502 may have different shapes when viewed from above. For example, the wells 502 may be square, round, rectangular, or other shape in plan view. The wells 502 may have different volumetric shapes, including cylindrical, rectangular prismatic, or other three-dimensional shapes.

[0101] FIG. 10 is a perspective view of an embodiment of the illumination panel 106 in an exploded configuration illustrating the layered construction of the illumination panel 106. As described above generally in connection with FIG. 1 - FIG. 3, the illumination panel 106 is configured to illuminate the plurality of wells 502 of the multi-well tissue suspension cartridge 102 and to define an opening array 204 through which light reflected from the fiducials 510 propagates toward the image sensor array 206.

[0102] As illustrated in FIG. 10, the illumination panel 106 comprises, from top to bottom, a diffuser plate 1002, an aperture plate 1004, a light source substrate 1006, and a thermal management layer 1008.Docket No. CURI-P27WO

[0103] The diffuser plate 1002 is disposed at the top of the illumination panel 106, facing the multi-well tissue suspension cartridge 102 when the cartridge is positioned within the tissue imaging instrument 300. in some embodiments, the diffuser plate 1002 comprises a holographic diffuser configured to distribute illumination from the light sources 1010 with controlled angular spread. The diffuser plate 1002 defines a plurality of openings through which illumination from the light sources 1010 is distributed. In operation, illuminating the wells comprises providing uniform illumination through the plurality of openings such that each well 502 receives consistent illumination conditions. Uniform illumination across wells supports consistent, boundary discrimination and reduces variation in fiducial detection conditions across the well array 202.

[0104] The aperture plate 1004 is disposed below the diffuser plate 1002 and defines the openings of the opening array 204. Each opening corresponds to a respective well 502 and is aligned with a corresponding image sensor of the image sensor array 206 to define an optical channel 208 (FIG. 2). In some embodiments, the aperture plate 1004 comprises a retroreflective upper surface configured to redirect illumination from the light sources 1010 toward the wells 502. The aperture plate 1004 further defines a plurality of light source cutouts 1202 (FIG, 12) through which respective light sources 1010 of the light source substrate 1006 extend, as described in more detail below in connection with FIG. 12.

[0105] The light source substrate 1006 is disposed below the aperture plate 1004 and provides a plurality of light sources 1010. In the illustrated embodiment, the light sources 1010 comprise surface-emitting light-emitting diodes (LEDs) arranged on the light source substrate 1006. In some embodiments, the light source substrate 1006 comprises a metal core printed circuit board (PCB) having a thermally conductive metal substrate configured to conduct heat from the light sources 1010 toward the thermal management layer 1008. A thermal interface material may be disposed between the light source substrate 1006 and the thermal management layer 1008 to enhance thermal coupling therebetween. The light sources 1010 may be arranged circumferentially around the openings of the opening array 204 such that each opening is illuminated by a plurality of surrounding light sources 1010. This circumferential arrangement contributes to uniform illumination of each well 502 through the corresponding opening. The spatial arrangement of the light sources 1010 on the light source substrate 1006 is described in more detail below in connection with FIG. 11.Docket No. CURI-P27WO

[0106] The thermal management layer 1008 is disposed at the bottom of the illumination panel 106, below the light source substrate 1006 (i.e., opposite the diffuser plate 1002). The thermal management layer 1008 defines a plurality of openings aligned with the opening array 204 and is configured to act as a heat sink for the illumination panel 106. In the illustrated embodiment, the thermal management layer 1008 comprises a liquid cooling plate through which a liquid coolant may be circulated. A coolant port 1012 is disposed on an edge of the thermal management layer 1008, between electrical connections for the light source substrate 1006, and is configured to receive the cooling liquid. A plurality of valves 1014 are disposed along edges of the thermal management layer 1008 to seal the cooling channels within the cooling plate. The liquid cooling plate may define coolant channels configured to route the liquid coolant between and around the plurality of openings defined by the thermal management layer 1008. In some embodiments, the coolant channels extend in a serpentine pattern between adjacent rows or columns of openings, such that the liquid coolant traverses the thermal management layer 1008 in a path that passes proximate each opening. In some embodiments, the coolant channels comprise a manifold region disposed adjacent the coolant port 1012 and a plurality of branching channels extending from the manifold region between the openings. The coolant channels may be defined within the interior of the liquid cooling plate, for example by forming internal passages within a unitary plate structure or between bonded plate halves. It should be appreciated that the particular routing geometry of the coolant channels may vary depending on the thermal load distribution across the illumination panel 106, and that serpentine, branching, grid, radial, or hybrid channel configurations may be employed. In some embodiments, coolant channels may further extend through the tissue imaging instrument 300 beyond the illumination panel 106, for example below the image module 104 or between one or more circuit boards associated with the image module 104, to remove heat generated by the image sensors and associated electronics. In some embodiments, the thermal management layer 1008 further comprises one or more temperature sensors, for example resistance temperature detectors (RTDs), disposed on or proximate the light source substrate 1006 and configured to monitor a local temperature of the illumination panel 106. The one or more temperature sensors may be communicatively coupled with a temperature controller configured to regulate the liquid coolant flow rate, the light source drive current, or both, in a closed-loop temperature control configuration. It should be appreciated that liquid cooling is one of several thermal management approaches. In other embodiments, the thermal management layer 1008 may additionally or alternatively comprise passive cooling elementsDocket No. CURI-P27WOsuch as one or more heat sinks configured to dissipate heat generated by the light sources 1010, and / or air-cooled cooling elements such as one or more fans configured to direct airflow across the illumination panel 106 or the image module 104

[0107] It should be appreciated that the layered construction of the illumination panel 106 positions the light sources 1010, the opening array 204, and the thermal management layer 1008 in a stacked arrangement such that the openings of each layer are aligned. This alignment ensures that each optical channel 208 extends through the illumination panel 106 from the well 502 through the opening array 204 to the corresponding image sensor of the image sensor array 206, as described above in connection with FIG. 2. In some embodiments, one or more spacer elements may be disposed between adjacent layers of the illumination panel 106 to establish a predetermined separation distance and to accommodate electrical or fluid connections between the layers.

[0108] FIG. 11 is a top plan view of the light source substrate 1006 of the illumination panel 106. As described above in connection with FIG. 10, the light source substrate 1006 comprises a printed circuit board (PCB) carrying the plurality of light sources 1010. As illustrated in FIG.11, the light sources 1010 are disposed at interstitial positions between adjacent openings of the opening array 204, such that each opening is surrounded by a plurality of light sources 1010 arranged circumferentially about the opening. In the illustrated embodiment, the light sources 1010 are positioned at the intersections of rows and columns defined by the opening array 204, providing uniform illumination to each well 502 through a corresponding opening. The light source substrate 1006 further comprises electrical connectors disposed along an edge of the light source substrate 1006 for providing electrical power to the light sources light source 1010. Coolant ports 1012 are disposed on opposing edges of the light source substrate 1006 and are configured to circulate cooling liquid through the thermal management layer 1008 disposed beneath the light source substrate 1006, as described above in connection with FIG. 10.

[0109] FIG 12 is a top plan view of the aperture plate 1004 of the illumination panel 106. As illustrated in FIG. 12, the aperture plate 1004 defines the openings of the opening array 204 and a plurality of light source cutouts 1202 disposed at interstitial positions between adjacent openings of the opening array 204. The light source cutouts 1202 are arranged in spatial correspondence with the light sources 1010 on the light source substrate 1006 (FIG. 11), such that each light source 1010 extends through a respective light source aperture cutout 1202 when the light source substrate 1006 and the aperture plate 1004 are assembled in the layeredDocket No. CURI-P27WOconfiguration described above in connection with FIG. 10. In this manner, the light source aperture cutouts 1202 position the light sources 1010 circumferentially around each opening of the opening array 204, enabling illumination to be directed toward the wells 502 from positions surrounding each opening. As further illustrated in FIG. 12, the retroreflective upper surface of the aperture plate 1004 is visible between the openings of the opening array 204 and the light source aperture cutouts 1202, the reflective upper surface being configured to redirect illumination from the light sources 1010 toward the wells 502, as described above in connection with FIG. 10.

[0110] FIG. 13 illustrates an embodiment of the image module 104 in a perspective view. The image module 104 provides the image sensor array 206 described above in connection with FIG. 2. As illustrated, the image module 104 may comprise a sensor printed circuit board (PCB) carrying a plurality of image sensors 1302 arranged in a grid corresponding to the well array 202 of the multi-well tissue suspension cartridge 102. Each image sensor 1302 is configured to image a respective fiducial 510 disposed within a corresponding well 502. In some embodiments, each image sensor 1302 has a lens disposed thereon, the lens configured to focus an image of the fiducial 510 onto the image sensor 1302 The focal point or focal range of each lens may be aligned with a plane extending between the pair of tissue supports 504 within each well 502. The image sensors 1302 are arranged on the sensor PCB in spatial correspondence with the openings of the opening array 204 defined by the illumination panel 106. In the assembled instrument configuration, the sensor PCB is mechanically aligned with the illumination panel 106 such that each image sensor 1302 is positioned at a terminus of a respective optical channel 208 (FIG. 2).

[0111] FIG 14 illustrates the image module 104 assembled to the illumination panel 106. As illustrated in FIG. 13, the image sensors 1302 extend through the openings of the illumination panel 106 when the image module 104 is mated with the illumination panel 106, with the multi¬ well tissue suspension cartridge 102 positioned above the illumination panel 106. In this assembled configuration, the image module 104 and the illumination panel 106 together define the optical alignment architecture 200 (FIG. 2) in which the well array 202, the opening array 204, and the image sensor array 206 are spatially aligned to establish the plurality of optical channels 208. This mechanical alignment between the image module 104 and the illumination panel 106 ensures that each image sensor 1302 receives image data from a corresponding well 502 through a dedicated optical channel 208, supporting the parallel image acquisition and per¬Docket No. CURI-P27WOwell fiducial position determination generally described above in connection with FIG. 1 - FIG.3 and in more detail below in connection with FIG. 17 - FIG. 20.

[0112] In some embodiments, each image sensor 1302 may comprise a complementary metal-oxide-semiconductor (CMOS) image sensor. Each image sensor 1302 may have a spatial resolution in a range of about 0.5 micrometers (pm) per pixel to about 50 um per pixel. In some embodiments, each image sensor 1302 may be configured to capture image data at a frame rate in a range of about 1 frame per second (fps) to about 1000 fps. The frame rate and spatial resolution may be selected based on the contractile dynamics of the tissue being analyzed.

[0113] Furthermore, each image sensor 1302 may include a pixel array comprising a plurality of pixel circuits arranged in a plurality of pixel circuit rows and a plurality of pixel circuit columns. The image sensor 1302 may further include readout circuitry coupled to the pixel array and configured to read out image data from the pixel circuits. In some embodiments, the image sensor 1302 may include control circuitry configured to control operation of the pixel array, including exposure timing and gain settings.

[0114] FIG. 15 and FIG. 16 illustrate an alternative embodiment of the illumination panel 106 employing an indirect illumination architecture. In this embodiment, the illumination panel 106 comprises a planar waveguide 1502 and light sources 210 configured to couple light into the planar waveguide 1502 via total internal reflection to provide uniform illumination of the wells 502 in the multi -well tissue suspension cartridge 102.

[0115] As illustrated in FIG. 16, the light sources 210 may be disposed along one or more edges of the planar waveguide 1502. Each light source 210 comprises a plurality of lightemitting diodes extending along an edge of the planar waveguide 1502. In some embodiments, the light sources 210 are bonded to optically polished edges of the planar waveguide 1502 using an optical index-matching adhesive. The uniform illumination emitted through the planar waveguide 1502 enables consistent imaging of the fiducials 510 by the image sensor array 206 from well to well.

[0116] The planar waveguide 1502 may be formed of a transparent polymer, such as, for example, extruded acrylic. As illustrated in FIG. 15, the planar waveguide 1502 defines the opening array 204, each opening corresponding to a respective well 502 and aligned with a corresponding image sensor of the image sensor array 206 to define an optical channel 208. The planar waveguide 1502 may provide at least 80% efficiency in both luminance andDocket No. CURI-P27WOuniformity. In some embodiments, the planar waveguide 1502 may comprise light-redirecting particles dispersed throughout the waveguide material as scattering particles configured to redirect photons back into the planar waveguide 1502 and ultimately through an exit surface thereof toward the fiducials 510. The light-redirecting particles may comprise metallic nanoparticles such as aluminum or silver nanoparticles. Additionally or alternatively, one or more surfaces of the planar waveguide 1502 may comprise a reflecting particle layer, for example a metallized layer formed by physical vapor deposition, configured to reflect photons from the light sources 210 back into the planar waveguide 1502. In some embodiments, a reflecting particle layer may be formed on a bottom surface, one or more side surfaces, and / or surfaces defining the openings of the opening array 204, but not on the exit surface, such that scattered photons are redirected through the exit surface toward the wells 502.

[0117] As illustrated in FIG. 16, the illumination panel 106 may further comprise light source support members 1504 disposed along the edges of the planar waveguide 1502. The light source support members 1504 extend inward toward a central region of the planar waveguide 1502 by a distance configured to block high-angle rays from the light sources 210 that would otherwise escape as stray light. In some embodiments, the light source support members 1504 serve as a thermal path from the light sources 210, being coupled to the planar waveguide 1502 with thermally conductive epoxy to form a bonded assembly. The light source support members 1504 may define coolant channels in a similar manner as described in connection with FIG. 10 and FIG. 11, through which a cooling liquid may be circulated. In this regard, coolant ports 1012 may be disposed at one or more corners of the illumination panel 106 for introducing the cooling liquid into the coolant channels of the light source support members 1504. In some embodiments, coolant channels may further extend through the tissue imaging instrument 300 beyond the illumination panel 106, for example below the image module 104 or between circuit boards associated with the image module 104, to remove heat generated by the image sensors and associated electronics. In other embodiments, the illumination panel 106 may additionally or alternatively employ passive cooling elements such as one or more heat sinks and / or air-cooled cooling elements such as one or more fans. It should be appreciated that the thermal management configurations described herein for the direct illumination embodiment of FIG. 10 - FIG. 12 and the waveguide embodiment of FIG. 15 and FIG. 16 are representative, and that the thermal management elements may be combined, substituted, or omitted depending on the thermal requirements of the particular implementation.Docket No. CURI-P27WO

[0118] FIG. 17 illustrates another embodiment of the image processing system 108, which may be incorporated in the tissue imaging system 100, As described above generally in connection with FIG. 1 - FIG. 4, the image processing system 108 communicates with the image module 104 to capture image data 1702 of fiducials disposed on tissue supports within the multi -well tissue suspension cartridge 102 and processes the captured image data 1702 to detect changes in fiducial position over time. The image processing system 108 determines positions of the fiducials 1802 (see FIG. 18A) based on second output path 1720 received from the image sensors 1704 and a predetermined geometry of the fiducials 1802. As illustrated in the embodiment of FIG. 17, the image processing system 108 may comprise a plurality of programmable logic devices 1708, multiplexing logic 1712, and a processing module 1714.

[0119] Image module 104 comprises a plurality of image sensors 1704. In an embodiment, each image sensor 1704 is configured to image a respective fiducial 1802. In certain embodiments, the fiducials may be provided in a multi-well tissue suspension cartridge 102, with each image sensor 1704 corresponding to a respective fiducial 1802, Each image sensor 1704 generates image 1102 (FIG. 18A) representing the imaged fiducial 1802. As described below in more detail, image data 1702 may comprise pixel intensity values arranged in a two-dimensional array that is received by the image processing system 108 and used to implement, in certain embodiments, row-based fiducial localization to determine fiducial position.

[0120] As further illustrated in FIG. 17, image processing system 108 further comprises rowbased fiducial localization logic 1710 which transforms image data 1702 into fiducial positions through row-based processing within the programmable logic devices 1708, consolidation via multiplexing logic 1712, and geometry-constrained positional determination within the processing module 1714, Different aspects of and functionality of the row-based fiducial localization logic 1710 may be executed by the programmable logic devices 1708 or the processing module 1714 depending on the implementation and architecture. It should be appreciated that by operating on row-based fiducial position data rather than full-frame image data, image processing system 108 may significantly reduce bandwidth and computational requirements compared to much more complex fiducial image analysis approaches. In this manner, in some embodiments, image data 1702 may be processed by the image processing system 108 without transmitting full-frame image data to a remote computing device 1716.

[0121] The plurality of programmable logic devices 1708 are configured to process the image data 1702 generated by the image module 104. In certain embodiments, the programmableDocket No. CURI-P27WOlogic devices 1708 may comprise field-programmable gate arrays, although other programmable logic devices and architectures may be used. As described below in more detail with reference to FIG. 18A - FIG 18F and FIG. 19, each programmable logic device 1708 is configured to evaluate one-dimensional row segments 1808 (FIG. 18B) of the image data 1702 (FIG. 18A) to generate row-based fiducial position data corresponding to row-based fiducial position estimates As illustrated in FIG. 17, in some embodiments, image processing system 108 may comprise an architecture in which the plurality of image sensors 1704 may be partitioned among the plurality of programmable logic devices 1708 such that each programmable logic device 1708 processes image data 1702 from a subset 1706 of the image sensors 1704.

[0122] Image processing system 108 may be implemented in various alternative architectures and with various alternative logic and / or processing devices. For example, as described below in more detail with reference to FIG. 20, the programmable logic devices 1708 may be arranged in a cascaded configuration in which row-based fiducial position data generated by one programmable logic device is provided to another programmable logic device. As illustrated in FIG. 17, in some implementations, at least one programmable logic device 1708 may provide row-based fiducial position data via a first output path 1718 to another programmable logic device 1708 or multiplexing logic 1712 and via a second output path 1720 to the processing module 1714.

[0123] Multiplexing logic 1712 is configured to combine row-based fiducial position data generated by the plurality of programmable logic devices 1708 In certain embodiments, multiplexing logic 1712 consolidates row-based fiducial position data received from multiple programmable logic devices into a reduced number of output channels provided to the processing module 1714. In this regard, it should be appreciated that programmable logic devices 1708 and multiplexing logic 1712 operate on row-based fiducial position data rather than full image data 1800.

[0124] The processing module 1714 is configured to receive the combined row-based fiducial position data and to determine a fiducial position based on the predetermined geometry of the fiducials 1802, which may be represented in the fiducial geometry model 110. It should be appreciated that the predetermined geometry may be stored in one or more of the programmable logic devices 1708 and the processing module 1714. As described below in more detail, in certain embodiments, the processing module 1714 may be configured toDocket No. CURI-P27WOgenerate a combined response (FIG. 18G) by aggregating row-based fiducial position estimates and determine the fiducial position from the combined response. The fiducial position may be determined with pixel-level or sub-pixel precision.

[0125] In some embodiments, the processing module 1714 may comprise one or more of a processor, a memory, and a non-transitory computer-readable medium storing instructions that, when executed by the processor, cause the processor to perform the associated operations, including receiving combined row-based fiducial position data and determining fiducial positions based on the predetermined geometry. The memory may comprise volatile memory, non-volatile memory, or a combination thereof, and may store intermediate computational results including row-based fiducial position data, combined response data, and determined fiducial positions. Similarly, each programmable logic device 1708 may comprise configuration memory storing logic implemented as configurable logic elements. The fiducial geometry model 110 may be stored in one or more of the programmable logic devices 1708 and the processing module 1714 as data, instructions, lookup tables, or configurable logic representations.

[0126] FIG. 18A - FIG. 18G illustrate an exemplary embodiment of the architecture, operation, and / or functionality of row-based fiducial localization logic 1710 for determining a fiducial position of a fiducial 1802 having a predetermined geometry. FIG. 18A - FIG. 18G may also represent schematic explanations of certain aspects, steps, or functions of various embodiments of methods for determining the position of a fiducial 1802 via row-based fiducial localization.

[0127] FIG. 18A illustrates an image frame 1800 associated with image data 1702 in which opposing fiducials 1802 are associated with the tissue localizer portions 1812 and tissue support structures, such as described above in connection with FIG. 5 - FIG. 9. In the illustrated embodiment, fiducials 1802 comprise high-contrast spherical bodies positioned relative to support posts with tissue 1804 suspended between opposing support structures. The fiducial 1802 may be imaged against a contrasting background to facilitate boundary discrimination.

[0128] In certain embodiments, a spherical geometry may be particularly well-suited to the contractility imaging context because its rotational symmetry provides a uniform boundary¬ profile regardless of the deflection angle of the tissue support, allowing the fiducial geometiy model 110 to remain valid as the flexible post assembly 514 deflects under tissue contraction.Docket No. CURI-P27WOAdditionally, a spherical fiducial 1802 creates a consistent and sharply contrasting edge against the tissue localizer portion 806 that may enable boundary determination even when the image sensor is not precisely in focus. In some embodiments, the high-contrast boundary between the fiducial 1802 and the tissue localizer portion 806 further enables the image processing system 108 to determine fiducial position in the presence of distractor objects such as bubbles, debris, or other artifacts that may appear within the well during culture and imaging. It should be appreciated, however, that the disclosed techniques may be applicable to fiducials 1802 having any predetermined geometry for which expected boundary variation across rows may be defined or modeled by image processing system 108. The predetermined geometry and / or fiducial geometry model 110 may correspond to a geometric model, stored representation, analytical expression, empirical calibration data, lookup table, or other information defining expected spatial characteristics of the fiducial 1802.

[0129] FIG. 18B schematically illustrates a portion of the two-dimensional image frame 1800 intersected by a plurality of one-dimensional row segments 1808 (labeled R1 - R9). Each one¬ dimensional row segment 1808 extends laterally across the image and intersects a plurality of pixel columns 1806. As illustrated in FIG. 18B, dashed vertical lines represent pixel columns 1806. Each pixel column 1806 corresponds to a discrete lateral sampling location of image frame 1800. Accordingly, each one-dimensional row segment 1808 comprises a sequence of pixel intensity values indexed by pixel column 1806. Referring to the schematic representation of FIG. 18B, the one-dimensional row segments 1808 that intersect the fiducial 1802 (R2 - R8 in the illustrated embodiment) contain boundary information, while the one-dimensional row segments 1808 outside the fiducial (R1 and R9) contain primarily background pixel data. In an exemplary embodiment, each one-dimensional row segment 1808 may be processed independently, allowing the two-dimensional image frame 1800 to be reduced to a plurality of one-dimensional evaluations along pixel columns 1806. It should be appreciated that this rowbased segmentation may significantly reduce computational complexity and enable streaming processing without requiring storage of a full two-dimensional pixel array.

[0130] FIG 18C illustrates example pixel intensity values along rows R2 - R8. In the schematic representation, for clarity, pixel values corresponding to background are represented by a first symbol (i.e., filled dots), and pixel values corresponding to the fiducial interior are represented by a second symbol (open circles). Each value is associated with a specific pixel column 1806 along a given one-dimensional row segment 1808. It should be appreciated that aDocket No. CURI-P27WOtransition between background-associated pixel columns and fiducial-associated pixel columns defines a boundary position for that one-dimensional row segment 1808. In this manner, boundary identification occurs at the pixel column level, and a row-based fiducial position estimate for a given one-dimensional row segment 1808 corresponds to a lateral coordinate indexed to one or more pixel columns 1806 at which a transition in pixel intensity, brightness, or related signal characteristic occurs. In connection with row-based fiducial localization logic 1710, FIG. 18C schematically represents pixel -level data from which boundary information may be derived, but it should be appreciated that the particular mechanism used to detect the transition may vary

[0131] FIG. 18D illustrates an exemplary embodiment for extraction of boundary positions from the one-dimensional row segments 1808. Each one-dimensional row segment 1808 may be evaluated to generate a row-based fiducial position estimate corresponding to a detected boundary pixel column 1806. In one implementation, evaluation may comprise detecting a transition in brightness, gradient, contrast, or other signal characteristic across adjacent pixel columns 1806. In some embodiments, evaluation of the one-dimensional row segment 1808 may include applying a one-dimensional operator or convolution kernel across sequential pixel column values 1806 within the one-dimensional row’ segment 1808. The convolution kernel may be configured to produce a boundary response indicative of a transition between background-associated pixel values and fiducial-associated pixel values.

[0132] In such embodiments, the row-based fiducial position estimate may correspond to a pixel column 1806 associated with a peak, threshold crossing, or other response characteristic of the convolution output. In other embodiments, alternative transition-detection mechanisms may be employed. While representative and advantageous boundary detection methods are detailed herein, it should be appreciated that, in other embodiments, any suitable boundary detection or other solution may be implemented by image processing system 108. Furthemore, a plurality of boundary positions may be detected for each one-dimensional row segment 1808, corresponding to opposing surfaces or edges of the fiducial 1802. In other embodiments, a single boundary position per row segment 1808 may be sufficient, to generate a row-based fiducial position estimate.

[0133] Referring to FIG. 18D, the detected boundary positions are illustrated as tick marks aligned wdth pixel columns 1806. Each tick mark represents a row-based fiducial position estimate derived from pixel-level data indexed to the corresponding pixel column 1806. TheDocket No. CURI-P27WOone-dimensional row segment 1808 located near extreme portions of the fiducial geometry may yield weaker or less reliable boundary estimates due to, for example, shorter chord length, reduced pixel span across pixel columns 1806, reduced contrast, or increased noise. Such onedimensional row segments 1808 may be weighted, filtered, selectively excluded, or otherwise treated differently during subsequent aggregation. In this manner, each row-based fiducial position estimate corresponds to a boundary coordinate indexed to one or more pixel columns 1806 and may be expressed in pixel-level form or, as described below in more detail, sub-pixel form using additional processing.

[0134] Because the expected boundary location varies across one-dimensional row segments 1808 according to the predetermined geometry, raw boundary' positions expressed in pixel column coordinates 1806 may not align laterally. FIG 18E illustrates an adjustment of the row-based fiducial position estimates based on the predetermined geometry. In one embodiment, each row-based boundary estimate, indexed to a pixel column 1806, is shifted or transformed according to an expected row-wise boundary variation defined by the predetermined geometry. The expected variation may be determined analytically, derived from the fiducial geometry model 110, defined by calibration data, or otherwise obtained. Following adjustment, boundary estimates originally associated with different pixel columns 1806 may be mapped to a common lateral reference coordinate such that corresponding geometric features align. The adjusted estimates comprise aligned boundary position responses in which boundary data from different rows has been corrected for the curvature of the fiducial. The aligned boundary position responses may then be combined to determine a fiducial position, as the geometric distortion across rows has been reduced.

[0135] FIG 18F illustrates row-level boundary responses following geometry-based adjustment. Each one-dimensional row segment 1808 contributes evidence regarding the fiducial position estimate along the lateral coordinate axis defined by pixel columns 1806. As illustrated in the embodiment of FIG. 18F, row segment responses may be represented as response curves defined over pixel column positions 1806. Row segments exhibiting strong boundary transitions generate stronger response magnitudes, while rows with weaker transitions generate lower response magnitudes. Because geometry-based adjustment has been applied, row-level responses corresponding to a common fiducial position are aligned across pixel columns 1806.Docket No. CURI-P27WO

[0136] It should be appreciated that row-based fiducial localization logic 1710 may not require explicit two-dimensional feature tracking across pixel arrays. Instead, in an embodiment, alignment may be achieved through geometry-constrained adjustment of independent one-dimensional row evaluations indexed to pixel columns 1806.

[0137] FIG. 18G illustrates aggregation of the adjusted row-level responses to generate a combined response along the lateral coordinate defined by pixel columns 1806. Aggregation may comprise summing, accumulating, weighting, or otherwise combining the adjusted rowbased fiducial position estimates or response values associated with each pixel column 1806. The combined response may exhibit a dominant peak corresponding to the fiducial position. In some embodiments, the fiducial position corresponds to a coordinate reference associated with the predetermined geometry, such as a center position derived from one or more boundary estimates. In certain embodiments, the peak location may be refined using, for example, interpolation between adjacent pixel columns 1806 to determine a sub-pixel fiducial position. Interpolation may comprise fitting a curve to response values surrounding the peak, performing multi-point estimation, or other peak refinement techniques.

[0138] Upon completion of the operations associated with one or more of the schematic representations of FIG. 18A - FIG. 18G, the determined fiducial position may be configured as a fiducial displacement output value associated with the tissue support structure and may be tracked across image frames to measure displacement.

[0139] It should be appreciated that, although FIG. 18A - FIG. 18G illustrate detection of a boundary of a spherical fiducial 1802 using pixel column indexing, the described techniques may be applied to opposing boundaries, paired boundary estimates, alternative geometric reference features, or fiducials having any non-spherical predetermined geometries or any other three-dimensional body having a surface profile that varies in cross-section along the tissue contraction axis extending between the tissue supports according to the predetermined geometry. Furthermore, row-based evaluation, geometry-based adjustment, response generation, and aggregation may be implemented in one or more of programmable logic devices 1708, processing module 1714, firmware, or other computational or processing elements or devices.

[0140] Having described the general architecture, logic, and / or functionality of image processing system 108, an exemplary method 1900 for determining a fiducial position from image data 1702 representing a fiducial 1802 having a predetermined geometry will beDocket No. CURI-P27WOdescribed with reference to FIG. 19. The method 1900 reduces two-dimensional image data 1702 into a plurality of one-dimensional row segments 1808, generates row-based fiducial position estimates, adjusts the row-based estimates according to the predetermined geometry, and combines the adjusted estimates to determine the fiducial position. It should be appreciated that method 1900 may be particularly suited for implementation in tissue imaging system 100 and executed by image processing system 108 in an edge-processing architecture.

[0141] At block 1902, image data 1702 representing a fiducial 1802 having a predetermined geometry is received. The image data 1702 may be generated by an image sensor 1704 positioned to image the fiducial 1802. In multi-well embodiments, a plurality of image sensors 1704 may generate image data 1702 corresponding to respective fiducials 1802. The image data 1702 may comprise pixel intensity values arranged in a two-dimensional array. The fiducial 1802 may have any predetermined geometric form suitable for positional determination. In some embodiments, the fiducial 1802 is spherical. However, the method 1900 applies to any fiducial 1802 comprising a three-dimensional body having a surface profile that varies in cross-section along the tissue contraction axis extending between the tissue supports according to the predetermined geometry.

[0142] At block 1904, the image data 1702 is segmented into a plurality of one-dimensional row segments 1808 Prior to detecting the plurality of boundary' positions from the row segments, the image data 1702 may be preprocessed by, for example, applying noise reduction or normalization. The one-dimensional row segments 1808 are then evaluated to generate corresponding row-based fiducial position estimates Each one-dimensional row' segment 1808 corresponds to a horizontal subset of pixel intensity values within the image data 1702. The one-dimensional row segments 1808 may be evaluated independently of one another.Evaluation of a one-dimensional row segment 1808 may include determining boundary position responses within the row segment 1808. In some embodiments, boundary' position responses are generated by applying a one-dimensional evaluation function across the one-dimensional row segment 1808 to detect transitions in pixel intensity corresponding to fiducial boundaries. The evaluation function may comprise a convolution kernel or other transition-detection mechanism. Each evaluated one-dimensional row segment 1808 produces a row-based fiducial position estimate. The estimate may represent a boundary location, a center-related estimate derived from opposing boundaries, or another position-related value derived from the one-Docket No. CURI-P27WOdimensional row segment 1808. In this manner, the row-based evaluation transforms the two-dimensional image data 1702 into a plurality of one-dimensional position estimates.

[0143] At block 1906, one or more of the row -based fiducial position estimates are adjusted based on the predetermined geometry'. Because the fiducial 1802 has a predetermined geometry, the boundary location observed within a given row segment 1808 may vary as a function of the vertical position of that one-dimensional row segment 1808 within the image frame 1800, Accordingly, adjustment may comprise shifting the row-based fiducial position estimates using a row-dependent geometric offset derived from the predetermined geometry. The geometric offset may define an expected boundary variation for each one-dimensional row segment 1808. In some embodiments, the adjustment may express the row-based fiducial position estimates relative to a fiducial position defined by the predetermined geometry. The geometric offset may be derived analytically from geometric parameters, empirically from calibration data, or from the fiducial geometry model 110

[0144] At block 1908, the adjusted fiducial position estimates are combined. Combining may include aggregating the adjusted estimates across a plurality of one-dimensional row segments 1808. In some embodiments, aggregation may comprise summing the adjusted fiducial position estimates to generate a combined response curve representing a likelihood of the fiducial position. Aggregation may reinforce position information that is consistent with the predetermined geometry and suppress inconsistent or noise-related responses.

[0145] In this manner, method 1900 determines the fiducial position associated with image frame 1800 from the combined adjusted position estimates. In some embodiments, the fiducial position may be determined by identifying a peak of the combined response curve, where the peak corresponds to a fiducial position. In further embodiments, determining displacement comprises interpolating a sub-pixel position of the peak to obtain a sub-pixel fiducial position. Sub-pixel interpolation may include evaluating neighboring response values to estimate a location between discrete pixel indices,

[0146] In some embodiments, the fiducial position may be determined without performing two-dimensional segmentation, contour extraction, or template matching. Instead, positional determination is achieved through evaluation of one-dimensional row segments and geometry-constrained alignment of row-based position information.

[0147] FIG 20 illustrates another embodiment of the image processing system 108 in which the programmable logic devices 1708 of FIG. 17 are implemented as a plurality of field- J9Docket No. CURI-P27WOprogrammable gate array (FPGA) devices 2000 multiplexed and arranged in a cascaded configuration. In the illustrated embodiment, the image module 104 provides the image data 1702 to the FPGA devices 2000 via one or more image data interfaces. Each FPGA device 2000 is configured to receive image data 1702 from at least one image sensor 1704. In some embodiments, the plurality of image sensors 1704 are partitioned among the plurality of FPGA devices 2000 such that each processes image data 1702 from a subset 1706 of the image sensors 1704.

[0148] Because the row-based fiducial localization logic 1710 operates on one-dimensional row segments 1808 rather than full two-dimensional image frames, the computational requirements per well are sufficiently constrained to be implemented within individual FPGA devices 2000. This enables the image processing system 108 to determine fiducial displacement contemporaneously with image acquisition across the full well array.

[0149] Each FPGA device 2000 may comprise row-based fiducial localization logic 1710 configured to evaluate one-dimensional row segments 1808 of the received image data 1702 to generate row-based fiducial position data as detailed above. In some embodiments, the FPGA devices 2000 sequentially process one-dimensional row segments 1808 without storing a full two-dimensional representation of the image data 1702.

[0150] In the embodiment illustrated in FIG. 20, at least a portion of the FPGA devices 2000 are arranged in a multiplexed cascaded configuration. Row-based fiducial position data generated by a first FPGA device 2000 may be provided to a second FPGA device 2000 via a first output path comprising an inter-device interface. In some embodiments, the inter-device interface enables aggregation or partial consolidation of row-based fiducial position data across multiple FPGA devices 2000.

[0151] As further illustrated in the embodiment of FIG. 20, each FPGA device 2000 may further provide row-based fiducial position data (or other data) along a second output path comprising data interface 2002 to a system-on-module (SoM) device 2004. The dual output paths may permit simultaneous forwarding of intermediate results and transmission of consolidated results toward the SoM device 2004. It should be appreciated that multiplexing logic 1712 (FIG. 17) may be implemented in the embodiment of FIG. 20 within one or more of the FPGA devices 2000 or as a separate component. Regardless of the implementation, SoM device 2004 receives the data from the final multiplexed FPGA devices 2000 in the cascadedDocket No. CURI-P27WOarrangement, and combines or consolidates row-based fiducial position data received from the FPGA devices 2000.

[0152] SoM device 2004 receives the combined row-based fiducial position data and determines a fiducial position based on the predetermined geometry. In some embodiments, the SoM device 2004 and / or edge computing device 2006 performs aggregation of aligned rowbased fiducial position data and may perform sub-pixel interpolation to generate a fiducial position output.

[0153] As further illustrated in FIG. 20, edge computing device 2006 may communicate with remote computing devices 1716 either locally via, for example, a local area network or any other communication network 2008.

[0154] The specific components and communication interfaces illustrated in FIG. 20 represent one implementation of the logical connections shown in FIG. 17. Other communication protocols, interface standards, routing configurations, or processing topologies may be used without departing from the architecture described with respect to FIG. 17.

[0155] Although FIG. 20 illustrates a cascaded arrangement of programmable logic devices, other configurations may be used, including parallel, tree-based, ring-based, or centralized arrangements. The illustrated embodiment is provided as one example implementation of distributed row-based fiducial processing.

[0156] It should be appreciated that the methods, systems, and logic described herein may be implemented as a computer program embodied in a non-transitory computer-readable media and executable by one or more processors. As used herein, a "processor" may refer to any one or more general-purpose processors, microprocessors, controllers, microcontrollers, field- programmable gate arrays, application-specific integrated circuits, digital signal processors, systems-on-module, or any combination thereof, including the programmable logic devices 1708, the processing module 1714, the SoM device 2004, and the edge computing device 2006 described herein. A "non-transitory computer-readable medium" may include any tangible storage medium that stores instructions or data accessible by a processor, including read-only memory, random-access memory, flash memory, solid-state storage, magnetic disk, optical disc, embedded firmware storage, configuration memory of a programmable logic device, or any combination thereof. The term "non-transitory" excludes transitory propagating signals but does not exclude volatile storage media that maintain stored data during powered operation.Docket No. CURI-P27WO

[0157] Instructions stored on a non-transitory computer-readable medium may be executed by one or more processors to perform any of the methods described herein, including the method 1900 of FIG 19 and the row-based fiducial localization logic 1710 described in connection with FIG 18A -FIG. 18G. In some embodiments, the instructions may be distributed across a plurality of non-transitory computer-readable media associated with respective processors. For example, a first portion of the row-based fiducial localization logic 1710 may be stored in configuration memory of the programmable logic devices 1708, while a second portion may be stored in memory associated with the processing module 1714 or the SoM device 2004. The fiducial geometry model 110 may be stored as data, instructions, lookup tables, or configurable logic representations in one or more non-transitory computer-readable media accessible to the image processing system 108.

[0158] It should further be appreciated that the functional block diagrams, architectural diagrams, and method flowcharts described herein represent logical arrangements and are not limited to any particular physical implementation. The described functions may be implemented in hardware, firmware, software, or any combination thereof References to "logic" herein encompass hardware circuits, firmware instructions, software instructions, configurable logic, or any combination thereof that performs the described function. The particular partitioning of functionality among components described herein is illustrative, and other allocations of the described functions among fewer, additional, or alternative processing components are within the scope of the present disclosure.

[0159] Various changes can be made to the embodiments of the present disclosure as could be reasonably contemplated in view of the above-described description by any person skilled in the art The following claims are presented as examples of embodiments of the present disclosure, but these claims should not be construed to limit other claims or other embodiments disclosed herein.

[0160] The detailed description set forth above in connection with the appended drawings, where like numerals reference like elements, are intended as a description of representative embodiments of the present disclosure and are not intended to represent the only embodiments. Each embodiment described in this disclosure is provided as an example or illustration and should not be construed as preferred or advantageous over other embodiments. The illustrative embodiments provided herein are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Similarly, any steps described herein may be interchangeable with otherDocket No. CURI-P27WOsteps, or combinations of steps, in order to achieve the same or substantially similar result. Further still, one or more features of any embodiment may be combined with one or more features of one or more embodiments to form additional embodiments, which are within the scope of the present disclosure.

[0161] Generally, the embodiments disclosed herein are non-limiting, and the inventors contemplate that other embodiments within the scope of this disclosure may include structures and functionalities from more than one specific embodiment shown in the FIGURES and described in the specification. It will be appreciated that variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present disclosure. Accordingly, it is expressly intended that all such variations, changes, and equivalents fall within the spirit and scope of the present disclosure as claimed. For example, the present disclosure includes additional embodiments having combinations of any one or more features described above with respect to the representative embodiments.

[0162] In the foregoing description, specific details are set forth to provide a thorough understanding of representative embodiments of the present disclosure. It will be apparent to one skilled in the art, however, that the embodiments disclosed herein may be practiced without embodying all the specific details. In some instances, well-known process steps have not been described in detail in order not to unnecessarily obscure various aspects of the present disclosure.

[0163] The present application may include references to directions, such as “first,” "second," "vertical," "horizontal," "front," "rear," "left," "right," "top," and "bottom," “below,” “around,” etc. These references, and other similar references in the present application, are intended to assist in helping describe and understand the particular embodiment (such as when the embodiment is positioned for use) and are not intended to limit the present disclosure to these directions or locations.

[0164] The present application may also reference quantities and numbers. Unless specifically stated, such quantities and numbers are not. to be considered restrictive, but exemplary of the possible quantities or numbers associated with the present application. Also in this regard, the present application may use the term "plurality" to reference a quantity or number. In this regard, the term "plurality" means any number that is more than one, for example, two, three, four, five, etc. The term "about," "approximately," etc., means plus or minus 5% of the stated value. The term "based upon" means "based at least partially upon." The term "between" includes the values recited in connection therewith. The expressions “at least one of A, B, or C"; “at least one ofDocket No. CURI-P27WOA, B, and C"; and “at least one of A, B, and / or C" have the same meaning, i.e., any one of the following conditions satisfy all of the foregoing expressions: A; B; C, AB; AC, BC; ABC.

Claims

1. Docket No. CURI-P27WOCLAIMSWhat is claimed is:

1. A method of determining a fiducial position in a tissue imaging system, the method comprising:receiving image data representing a fiducial having a predetermined geometry; evaluating a plurality of one-dimensional row segments associated with the image data to generate a plurality of corresponding row-based fiducial position estimates;adjusting one or more of the plurality of row-based fiducial position estimates based on the predetermined geometry; andcombining the adjusted fiducial position estimates to determine the fiducial position.

2. The method of claim 1, wherein the predetermined geometry corresponds to a spherical fiducial.

3. The method of claim 1, wherein the adjusting the one or more of the plurality of row-based fiducial position estimates based on the predetermined geometry comprises shifting the rowbased fiducial position estimates based on an expected boundary variation defined by the predetermined geometry.

4. The method of claim 1, wherein the combining the adjusted fiducial position estimates comprises summing the adjusted fiducial position estimates.

5. The method of claim 1, wherein the fiducial position is determined by interpolating a peak of a combined response to determine a sub-pixel fiducial position.

6. The method of claim 1, wherein the fiducial position corresponds to displacement of a tissue support structure.

7. A tissue imaging system comprising:an image sensor array comprising a plurality of image sensors, each image sensor configured to image a respective fiducial of a plurality of fiducials, each of the plurality of fiducials having a predetermined geometry;Docket No. CURI-P27WOa plurality of programmable logic devices configured to process image data generated by the image sensor array, each programmable logic device configured to evaluate onedimensional row segments of the image data to generate row-based fiducial position data; multiplexing logic configured to combine the row-based fiducial position data generated by the plurality of programmable logic devices; anda processing module configured to receive the combined row-based fiducial position data and to determine a fiducial position for the respective fiducial based on the predetermined geometry.

8. The tissue imaging system of claim 7, wherein the programmable logic devices comprise field-programmable gate arrays9. The tissue imaging system of claim 7, wherein the plurality of image sensors are partitioned among the plurality of programmable logic devices such that each programmable logic device processes image data from a subset of the plurality of image sensors.

10. The tissue imaging system of claim 7, wherein the programmable logic devices are configured to process the one-dimensional row segments without storing a two-dimensional representation of the image data.

11. The tissue imaging system of claim 7, wherein the programmable logic devices are configured to sequentially process the one-dimensional row segments.

12. The tissue imaging system of claim 7, wherein the fiducial position is generated as an output signal without transmitting the image data to an external device.

13. The tissue imaging system of claim 7, wherein at least a portion of the plurality of programmable logic devices are arranged in a cascaded configuration such that row-based fiducial position data generated by one programmable logic device is provided to another programmable logic device.

14. The tissue imaging system of claim 7, wherein at least one of the programmable logic devices is configured to provide row-based fiducial position data along a first output path to another programmable logic device and along a second output path toward the processing module.Docket No. CURI-P27WO15. The tissue imaging system of claim 7, wherein the multiplexing logic is configured to consolidate row-based fiducial position data received from the plurality of programmable logic devices into a reduced number of output channels provided to the processing module.

16. A computer program embodied in a non-transitory computer readable medium and executable by a processor for determining a fiducial position in a tissue imaging system, the computer program comprising logic configured to:receive image data representing a fiducial having a predetermined geometry; evaluate a plurality of one-dimensional row segments of the image data to determine corresponding boundary position responses;align the corresponding boundary position responses based on the predetermined geometry; andcombine the aligned boundary position responses to determine a fiducial position.

17. The computer program of claim 16, wherein the logic configured to evaluate the plurality of one-dimensional row segments of the image data comprises logic configured to apply a one¬ dimensional convolution kernel along each row segment.

18. The computer program of claim 16, wherein the logic configured to evaluate the plurality of one-dimensional row segments of the image data comprises logic configured to generate responses for opposing boundaries of the fiducial within each row segment.

19. The computer program of claim 16, wherein the logic configured to determine the fiducial position comprises logic configured to interpolate a peak of a combined response curve to determine a sub-pixel fiducial position.

20. The computer program of claim 16, wherein the logic configured to align the corresponding boundary position responses comprises logic configured to shift the boundary' position responses based on a row-dependent geometric offset derived from the predetermined geometry¬ relative to a fiducial center location defined by the predetermined geometry.

21. A tissue imaging instrument comprising:an illumination panel configured to illuminate a multi-well tissue suspension cartridge comprising a plurality of wells arranged in a well array, each of the plurality of wells comprising a pair of tissue supports configured to suspend a tissue sample, at least one of theDocket No. CURI-P27WOpair of tissue supports having a fiducial defining a three-dimensional body having a predetermined geometry;an image module comprising a plurality of image sensors arranged in an image sensor array, the image sensor array arranged relative to the well array such that each image sensor corresponds to a respective well and is configured to image the fiducial within that well; and a processor in communication with the image module and the illumination panel, the processor comprising logic configured, for each image sensor to:detect a plurality of boundary positions of the respective fiducial within image data generated by that image sensor, the boundary positions corresponding to the predetermined geometry; anddetermine displacement of the respective tissue support based on changes in the plurality of boundary positions across image frames generated by that image sensor.

22. The tissue imaging instrument of claim 21, wherein the predetermined geometry comprises a spherical fiducial surface.

23. The tissue imaging instrument of claim 21, wherein the predetermined geometry is symmetric about a central axis.

24. The tissue imaging instrument of claim 21, wherein the plurality of boundary positions comprise opposing boundary positions corresponding to opposite sides of the fiducial.

25. The tissue imaging instrument of claim 21, wherein a plurality of programmable logic devices are configured to process the image data from respective subsets of the plurality of image sensors, each programmable logic device generating boundary position data provided to the processor.

26. The tissue imaging instrument of claim 21, wherein the illumination panel defines an opening array comprising a plurality of openings arranged in spatial correspondence with the image sensor array such that each opening is aligned with a respective image sensor.

27. The tissue imaging instrument of claim 26, wherein the illumination panel comprises a plurality of light sources arranged circumferentially around the openings of the opening array and configured to provide uniform illumination to the plurality of wells.Docket No. CURI-P27WO28. The tissue imaging instrument of claim 21, wherein determining displacement comprises aggregating the plurality of boundary positions to determine a fiducial center and tracking changes in the fiducial center across image frames29. The tissue imaging instrument of claim 21, wherein the processor is configured to transmit displacement data for each image sensor to a user interface contemporaneously with image acquisition.

30. The tissue imaging instrument of claim 26, wherein the illumination panel comprises a thermal management layer defining a plurality of openings aligned with the opening array and configured to distribute cooling across the illumination panel.

31. The tissue imaging instrument of claim 25, wherein the programmable logic devices are configured to process the image data without storing a two-dimensional representation of the image data.

32. A tissue imaging system comprising:an image module comprising a plurality of image sensors arranged in an image sensor array;an illumination panel comprising a plurality of light sources and defining an opening array comprising a plurality of openings arranged in spatial correspondence with the image sensor array such that each opening of the opening array is aligned with a respective image sensor; anda multi-well tissue suspension cartridge comprising a plurality of wells arranged in a well array, each of the plurality of wells comprising a pair of tissue supports configured to suspend a tissue sample, at least one of the pair of tissue supports having a fiducial defining a three-dimensional body having a predetermined geometry, the well array positioned such that each well aligns with a respective opening of the opening array and the respective image sensor.

33. The tissue imaging system of claim 32, wherein each opening defines an illumination channel corresponding to a respective well and image sensor.Docket No. CURI-P27WO34. The tissue imaging system of claim 32, wherein the plurality of light sources are arranged circumferentially around the openings of the opening array and configured to provide uniform illumination across the well array.

35. The tissue imaging system of claim 32, wherein the predetermined geometry comprises a spherical surface.

36. The tissue imaging system of claim 32, wherein the predetermined geometry is symmetric about a central axis37. The tissue imaging system of claim 32, wherein at least one of the pair of tissue supports is deflectable along an axis extending between the pair of tissue supports.

38. The tissue imaging system of claim 37, wherein the fiducial is disposed on the at least one deflectable tissue support.

39. The tissue imaging system of claim 32, wherein the pair of tissue supports comprise a tissue localizer portion defining a narrowed center region configured to center the tissue sample between the pair of tissue supports.

40. The tissue imaging system of claim 39, wherein the tissue localizer portion defines a contrasting visual backdrop adjacent to the fiducial.

41. The tissue imaging system of claim 32, wherein each well comprises a pair of fiducials, each fiducial disposed on a respective one of the pair of tissue supports.

42. The tissue imaging system of claim 32, further comprising a processor configured to determine displacement of the tissue support based on changes in a plurality of boundary positions of the fiducial across image frames generated by the image sensor array.

43. The tissue imaging system of claim 42, wherein the processor is configured to determine a fiducial center based on the predetermined geometry.

44. The tissue imaging system of claim 42, wherein a plurality of programmable logic devices are configured to process image data generated by the image sensor array to detect the plurality of boundary positions of the fiducial.Docket No. CURI-P27WO45. The tissue imaging system of claim 42, wherein the processor is configured to transmit displacement data to a user interface contemporaneously with image acquisition.

46. The tissue imaging system of claim 32, wherein the illumination panel comprises a thermal management layer defining a plurality of openings aligned with the opening array and configured to distribute cooling across the illumination panel.

47. A method of analyzing a tissue sample comprising:illuminating a plurality of wells of a multi-well tissue suspension cartridge, each well comprising a pair of tissue supports configured to suspend a tissue sample and at least one fiducial defining a three-dimensional body having a predetermined geometry;capturing image data representing the fiducials over a plurality of image frames; for each fiducial, detecting a plurality of boundary positions of the fiducial within the image data; anddetermining displacement of a respective tissue support based on changes in the plurality of boundary positions across the plurality of image frames.

48. The method of claim 47, further comprising aligning the plurality of wells such that each well corresponds spatially to a respective image sensor prior to detecting the plurality of boundary positions.

49. The method of claim 47, wherein the predetermined geometry comprises a spherical surface.

50. The method of claim 47, wherein the detecting the plurality of boundary positions comprises evaluating a plurality of one-dimensional row segments of the image data to identify corresponding boundary positions.

51. The method of claim 47, wherein the determining displacement comprises adjusting the plurality of boundary positions based on the predetermined geometry prior to combining the adjusted boundary positions52. The method of claim 47, where the determining displacement comprises aggregating the plurality of boundary positions to determine a fiducial center and tracking changes in the fiducial center across the plurality of image frames.Docket No. CURI-P27WO53. The method of claim 47, wherein the determining displacement comprises interpolating a sub-pixel position from the plurality of boundary positions.

54. The method of claim 47, further comprising transmitting displacement data to a user interface contemporaneously with capturing the image data.

55. The method of claim 47, further comprising casting the tissue sample onto the pair of tissue supports prior to illuminating.

56. The method of claim 47, wherein the illuminating comprises providing uniform illumination through a plurality of openings aligned with respective wells of the multi-well tissue suspension cartridge.

57. A multi-well tissue suspension cartridge comprising:a plurality of wells arranged in a well array;a pair of tissue supports disposed within each well and configured to suspend a tissue sample, at least one of the pair of tissue supports being deflectable along an axis extending between the pair of tissue supports; andat least one fiducial disposed on the at least one deflectable tissue support in each well, the fiducial defining a three-dimensional body having a surface profile that varies in cross- section along the axis according to a predetermined geometric relationship.

58. The multi-well tissue suspension cartridge of claim 57, wherein the three-dimensional body comprises a spherical shape.

59. The multi-well tissue suspension cartridge of claim 57, wherein at least a portion of the fiducial defines a curved surface such that the cross-section varies continuously along the axis.

60. The multi-well tissue suspension cartridge of claim 57, wherein the predetermined geometric relationship corresponds to a radial distance function along the axis.

61. The multi-well tissue suspension cartridge of claim 57, wherein the pair of tissue supports comprise a rigid support and a flexible support on which the fiducial is disposed.

62. The multi-well tissue suspension cartridge of claim 57, wherein the fiducial comprises a high-contrast material.Docket No. CURI-P27WO63. The multi-well tissue suspension cartridge of claim 57, wherein a flexure of the at least one deflectable tissue support comprises a thermoplastic material.

64. The multi-well tissue suspension cartridge of claim 57, wherein the pair of tissue supports comprise a tissue localizer portion configured to receive the tissue sample.

65. The multi- ’ell tissue suspension cartridge of claim 64, wherein the tissue localizer portion defines a narrowed portion of the tissue supports configured to center the tissue sample between the pair of tissue supports.

66. The multi-well tissue suspension cartridge of claim 57, wherein the at least one deflectable tissue support is configured to deflect along an axis in response to contraction of the tissue sample.

67. The multi-well tissue suspension cartridge of claim 57, wherein the fiducial defines a boundary between a first optical region and a second optical region having different optical characteristics.

68. The multi-well tissue suspension cartridge of claim 57, wherein the fiducial is integrally formed with the tissue support,69. The multi-well tissue suspension cartridge of claim 57, wherein the surface profile is defined such that a plurality of parallel cross-sections of the three-dimensional body perpendicular to the axis define boundary positions that conform to the predetermined geometric, relationship.

70. The multi-well tissue suspension cartridge of claim 69, wherein a fiducial center is determinable from the boundary positions of the plurality of parallel cross-sections.

71. The multi-well tissue suspension cartridge of claim 57, wherein at least one of the pair of tissue supports is coupled to a lid member disposed over the well.

Images