Bimodal imaging optical system for brain surgery navigation

Abstract

The invention discloses a bimodal imaging optical system for brain surgery navigation, and belongs to the technical field of brain surgery imaging and navigation. The system adopts a split design of an optical machine head and an OCT module and is connected through a single-mode optical fiber. The light machine head comprises a large objective lens group, a dichroscope, a spectroscope, a lighting lens, a dodging lens, a light source, a front fixed lens, a zoom lens, a rear fixed lens, an imaging camera, a three-dimensional galvanometer and a collimator; the OCT module comprises a coupler, a frequency sweeping light source, a polarization controller, a dispersion compensation assembly, an optical path compensation assembly and a photoelectric detector. According to the system, through light splitting and light path multiplexing of the dichroscope, high-definition color images (300-850 nm) on the surface of brain tissue and deep high-precision OCT cross-sectional images (950-1300 nm) can be simultaneously and coaxially obtained in real time, and the problem that surface and inner images cannot be synchronously obtained through an existing operating microscope is solved. The system is high in integration level and good in flexibility, can provide accurate intraoperative navigation for doctors, and remarkably improves the safety and accuracy of an operation.

Description

Technical Field

[0001] This invention belongs to the field of intraoperative imaging and navigation technology in neurosurgery, specifically relating to a dual-modal imaging optical system for navigation in neurosurgery. Background Technology

[0002] In neurosurgery, delicate procedures such as tumor resection, localization of epileptic foci, and treatment of vascular malformations all rely on real-time, high-resolution visualization and precise navigation of brain tissue structures during surgery. Currently, neurosurgery primarily utilizes the magnified optical field provided by surgical microscopes. This technology can present high-resolution color surface images of the surgical area, significantly improving the conditions for direct observation during surgery.

[0003] However, existing surgical microscopy techniques have significant limitations, specifically in the following aspects: 1) Limited imaging modality, unable to simultaneously acquire surface and internal information: Existing surgical microscopes can only provide two-dimensional color images of the tissue surface, unable to simultaneously acquire three-dimensional tomographic information (such as OCT images) of deep tissues in the same time and optical path. If surgeons need to observe subcortical structures, tumor boundaries, or microvascular pathways during surgery, they must rely on separate OCT equipment, resulting in a separation of image acquisition in time and space, failing to achieve true "simultaneous observation of surface and internal structures." 2) Limited navigation accuracy and insufficient deep structure identification: Due to the lack of real-time, high-resolution tomographic imaging capabilities, existing systems struggle to accurately identify the tumor infiltration front, microvessels, or functional area boundaries during surgery. Surgeons relying solely on surface images for resection operations are prone to residual lesions or accidental damage to important structures, affecting the safety and thoroughness of the surgery. 3) Low system integration and poor operational flexibility: Traditional OCT equipment is typically bulky and complex, making it difficult to integrate flexibly with surgical microscopes or robotic arms. Integrated designs are often cumbersome and difficult to adjust, unable to meet the multi-angle, small-space, and highly flexible operational requirements of neurosurgery, limiting their application in complex surgical fields. 4) Optical path separation leads to registration difficulties and increases cognitive burden: If a microscope and an independent OCT device are used simultaneously, their optical paths are independent and their perspectives are different. Doctors need to perform image registration and information fusion in their minds, which not only interrupts the surgical procedure but also increases the complexity of the operation and cognitive load, reducing the intuitiveness and real-time performance of navigation. 5) Rigid imaging function and lack of dynamic adjustment capability: The field of view and magnification of existing microscopes are usually fixed or have a limited adjustment range, making it impossible to achieve continuous zoom observation without changing the object distance. It is difficult to meet the needs of large-scale positioning and local detail examination at the same time, limiting the adaptability of intraoperative observation. 6) The stability and imaging quality of the OCT system are limited by traditional design: Traditional OCT systems mostly use spatial optical path or hybrid optical path designs, which are easily affected by factors such as vibration and temperature drift. Moreover, the dispersion and optical path compensation are not flexible enough, which may lead to a decrease in image resolution and insufficient signal-to-noise ratio, affecting the clear imaging of deep structures. 7) Insufficient spectral crosstalk and band management: When attempting to integrate multimodal imaging, existing systems often lack efficient spectral separation mechanisms. Visible light and near-infrared light are prone to crosstalk, affecting the purity of images from each modality and diagnostic reliability. 8) Optical layout does not follow strict conjugate relationships, affecting imaging and scanning accuracy: Many integrated systems do not fully consider the object-image conjugate relationship of illumination, imaging, and scanning optical paths, resulting in uneven illumination, blurred imaging, or scanning distortion, making it difficult to simultaneously achieve high-quality color imaging and accurate OCT tomography. 9) Existing integrated designs are difficult to adapt to the unique environmental requirements of neurosurgery: In recent years, to achieve multimodal imaging fusion, devices integrating visible light imaging and OCT have emerged (such as color three-dimensional fundus imaging systems for ophthalmic examinations).While these integrated devices have some applications in diagnostic scenarios, their inherent design philosophy and structural characteristics are completely unsuitable for the demanding environment of neurosurgical navigation. Specifically: They are bulky and lack flexibility: The integrated design encapsulates all modules—light source, detection, scanning, and imaging—into a single housing, resulting in a large and heavy device. In neurosurgery, the surgical field is extremely limited and requires flexible observation from multiple angles. The bulky device is difficult to move precisely and quickly position, and cannot be easily integrated into surgical microscopes or robotic arms, severely limiting its application in complex, deep surgical fields. It violates aseptic surgical principles: Neurosurgery requires extremely strict aseptic environments. The bulky integrated device makes disinfection, sterile covering, and intraoperative manipulation extremely difficult if frequent access to or entry into the sterile area is required, significantly increasing the risk of surgical infection and operational complexity. It cannot meet the needs of real-time dynamic navigation: Neurosurgical navigation requires the imaging system to respond to the surgeon's intentions in real time, providing immediate and accurate imaging of the area of ​​interest. Integrated devices are complex to adjust and inconvenient to move, making it difficult to achieve fast and easy operation of the imaging front end, which seriously affects the real-time performance of navigation and the smoothness of interaction. Poor scalability and adaptability: The optical path and structure of integrated designs are usually fixed, making it difficult to flexibly adjust or modularly replace them according to different surgical instruments (such as endoscopes and puncture needles) or different intraoperative needs (such as changing objectives with different working distances or magnifications), and lacking the ability to cope with diverse surgical scenarios.

[0004] Therefore, developing a dual-modal optical system that can truly synchronize, coaxially, and integrate high-definition color imaging and high-precision OCT tomography imaging of the surgical area, and is specifically optimized for the neurosurgical environment, possessing high flexibility, high stability, and high imaging quality, has become an urgent need for the development of neurosurgical navigation technology. This invention addresses these issues by proposing an innovative dual-modal imaging optical system to improve the precision, safety, and operational efficiency of neurosurgery. Summary of the Invention

[0005] The purpose of this invention is to provide a dual-modal imaging optical system for navigation in neurosurgery. This system can simultaneously, coaxially, and in real time acquire high-definition color images of the surface of the surgical area and high-precision OCT tomographic images of the deep layers, thereby solving the problem that existing surgical microscopes have a single imaging modality and cannot achieve simultaneous "surface and interior observation", significantly improving the accuracy and operational safety of neurosurgery navigation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In one aspect, a dual-modal imaging optical system for navigation in neurosurgery is provided.

[0007] A dual-modal imaging optical system for navigation in neurosurgery, characterized in that it includes a separate optical head and an OCT module connected by a single-mode optical fiber; The optical head is a compact optical module that integrates illumination, color imaging, and an OCT beam spatial scanning and coupling interface. Its optical components include: The large objective lens group has a wide spectral transmission characteristic covering the wavelength range of 300nm to 1300nm, and is used for focusing and collimating visible and near-infrared light. The dichroic mirror, located behind the large objective lens group, is configured to transmit visible light in the 300-850nm band and reflect near-infrared light in the 950-1300nm band. It is a key component for realizing the splitting and combining of visible and near-infrared light. The beam splitter is located behind the dichroic mirror; The illumination lens and the homogenizing lens are located behind the beam splitter and together with the light source form the illumination light path. They are used to generate and homogenize visible light, which is then irradiated onto the surgical area through the beam splitter, dichroic mirror and large objective lens group. The front fixed lens, the zoom lens, and the rear fixed lens are located sequentially in the direction of the reflected light path of the beam splitter. The zoom lens is an electrically movable lens used to continuously adjust the imaging magnification without changing the system's working distance. An imaging camera, located behind a fixed rear lens, is used to receive visible light transmitted through the color imaging optical path and form a high-definition color image; A three-dimensional galvanometer is located in the direction of the reflected light path of the dichroic mirror; A collimator, located behind the three-dimensional galvanometer, is used to realize the mutual conversion between spatial beams and fiber beams; The OCT module is an all-fiber independent functional unit, connected to the collimator of the optical head via the single-mode fiber, and includes: First coupler and second coupler; Frequency-sweeping light source, used to generate frequency-sweeping lasers in the 950-1300nm wavelength band; A polarization controller is used to regulate the polarization state of a light beam. Dispersion compensation components and optical path compensation components are used to accurately compensate for the optical path difference and group dispersion of the system; Photodetectors are used to receive interference signals and convert them into electrical signals; The illumination light path consists of the light source, the homogenizing lens, the illumination lens, the beam splitter, the dichroic mirror, and the large objective lens group, which are used to provide uniform visible light illumination to the surgical area. The color imaging optical route is composed of the large objective lens group, dichroic mirror, beam splitter, front fixed lens, zoom lens, rear fixed lens and imaging camera in sequence, and is used to receive and image the visible light reflected from the surgical area. The OCT imaging optical route is composed of the sweep frequency light source, the first coupler, the polarization controller, the dispersion compensation component, the optical path compensation component, the second coupler, the photodetector, and the collimator, the three-dimensional galvanometer, the dichroic mirror, and the large objective lens group in the optical head, which are used to perform high-resolution tomographic scanning of the inside of tissues.

[0008] Furthermore, the illumination lens and the uniform light lens constitute a 4F illumination system to ensure the uniformity of illumination.

[0009] Furthermore, the three-dimensional galvanometer is located at the rear focal plane of the large objective lens group to ensure that the scanning beam is distortion-free.

[0010] Furthermore, the system also includes a navigation display for synchronously or fusedly displaying the color image acquired by the imaging camera and the OCT tomographic image reconstructed by the photodetector.

[0011] Furthermore, the single-mode optical fiber between the optical head and the OCT module can be embedded in the robotic arm pipeline channel connecting the two.

[0012] Secondly, a navigation method for neurosurgery is provided.

[0013] A neurosurgical navigation method, characterized by using the aforementioned dual-modal imaging optical system, includes the following steps: S1: System Deployment and Surgical Area Preparation: Mount the optical imaging head onto the surgical microscope or robotic arm, complete aseptic processing, and connect the system. Adjust the position of the optical imaging head so that the brain tissue to be imaged is within the working distance of the large objective lens group.

[0014] S2: Surface Color Imaging and Real-time Macroscopic Navigation: The illumination source and imaging camera are activated to acquire and display high-resolution color images of the surgical area in real time for macroscopic anatomical observation and instrument navigation. During this process, the zoom lens can be continuously adjusted to change the magnification.

[0015] S3: Target-Guided OCT Tomography and Microscopic Navigation: Guided by real-time color images, the target area requiring deep exploration is identified. OCT imaging is initiated, and the three-dimensional galvanometer guides the OCT beam to scan the target area. The photodetector receives the interference signal and reconstructs the OCT tomographic image in real time.

[0016] S4: Dual-modal information fusion and composite navigation decision-making: Real-time color images and real-time OCT tomographic images are displayed synchronously, in split-screen, or fused on the same navigation interface. Doctors make precise surgical decisions and operations based on the fused macroscopic and microscopic information.

[0017] Compared to existing technologies, it has the following beneficial effects: 1. Real-time synchronization and coaxial acquisition of intraoperative dual-modal information were achieved. By employing a large objective lens group and a dichroic mirror, the system ensures strict alignment of illumination, color imaging, and the three optical axes of OCT. This allows for the simultaneous acquisition of high-resolution color surface images (300-850nm) and OCT tomographic images (950-1300nm) of the surgical area, with simultaneous or fused display on the navigation monitor. Surgeons can acquire composite information on macroscopic anatomy and microscopic depths within the same field of view and at the same time, without needing to switch devices or perform intracranial registration. This significantly reduces cognitive burden and enhances the intuitiveness and timeliness of surgical decisions.

[0018] 2. Significantly improved the accuracy and operational safety of surgical navigation. OCT imaging optical paths possess micron-level resolution, enabling real-time in-situ tomographic scanning of subcortical structures, tumor boundaries, and microvessels. Combined with precise control of a 3D galvanometer, it achieves sub-millimeter-level navigation capabilities, facilitating real-time identification of the tumor invasion front, avoidance of functional areas and important blood vessels during resection. This improves resection integrity, protects neurological function, and reduces the risk of intraoperative bleeding and injury.

[0019] 3. The use of a split design with single-fiber connection greatly enhances the system's flexibility and surgical adaptability. The optical sensor head and OCT module adopt a separate structure, connected by only a single-mode optical fiber, which is built into the robotic arm. This design makes the optical sensor head lightweight and miniaturized, facilitating integration into surgical microscopes, robotic arms, or handheld instruments, and adapting to various surgical approaches and complex surgical fields; at the same time, it keeps the bulky main unit away from the surgical area, freeing up operating space and meeting the stringent requirements of neurosurgery for sterility and flexibility.

[0020] 4. By using a common optical path and reusing key components, the system achieves high integration and performance optimization. The illumination, color imaging, and OCT optical paths share a large objective lens group and a dichroic mirror in the core section, resulting in a compact structure and strong optical path consistency. The illumination optical path uses a 4F lens group (illumination lens plus a homogenizing lens) to achieve uniform illumination. The color imaging optical path uses a variable zoom lens group (front fixed lens, zoom lens, and rear fixed lens) to support continuous zoom. This design significantly improves the system's integration and stability while ensuring image quality.

[0021] 5. Enhanced the intraoperative observation adaptability of color imaging. The color imaging optical path uses a movable zoom lens, which can continuously adjust the imaging magnification without changing the working distance. Doctors can seamlessly switch between a wide field of view (for positioning and path planning) and a high-magnification field of view (for detailed observation) according to the needs of the surgery, achieving a flexible combination of "macro positioning" and "microscopic examination".

[0022] 6. Innovative all-fiber OCT module and dispersion path compensation technology ensure high-quality tomographic imaging. The OCT module employs an all-fiber design, connecting each component via a first and second coupler. It integrates dispersion compensation and optical path compensation components to achieve precise compensation for system optical path difference and group dispersion. The all-fiber structure provides strong anti-interference capabilities and signal stability, ensuring that OCT images consistently maintain high resolution and a high signal-to-noise ratio.

[0023] 7. Precise band management and optical design effectively avoid intermodal crosstalk and expand system functionality. The dichroic mirror (A2) strictly transmits visible light (300-850nm) and reflects near-infrared light (950-1300nm), while the large objective lens group (A1) has a wide wavelength coverage of 300-1300nm, achieving spectral separation and crosstalk-free imaging, and reserving optical bandwidth for future expansion to multispectral or fluorescence imaging functions.

[0024] 8. The clearly defined conjugate relationship between key components and the object lays the physical foundation for high-quality imaging and precise scanning. The system's optical layout strictly adheres to the principle of object-image conjugation: brain tissue is located on the front focal plane of the large objective lens group, while the beam splitter and 3D galvanometer are located on the rear focal plane of the large objective lens group. The beam splitter also serves as the object plane for both the 4F lens group and the variable focal plane lens group. This design ensures uniform illumination, clear imaging, and distortion-free beam scanning, providing a solid foundation for the overall system performance. Compared to existing technologies, this invention not only solves the core problem of the inability to simultaneously acquire surface and tomographic images, but also provides a real-time, precise, and user-friendly dual-modal image navigation solution for neurosurgery through its flexible, highly integrated design. This has significant value in improving the precision and minimally invasive nature of neurosurgery, and possesses greater clinical value and market potential.

[0025] 9. Specifically designed for the neurosurgical environment, this invention solves the feasibility problem of traditional integrated devices in the operating room: The modular, lightweight design of this invention allows the system to seamlessly integrate into existing neurosurgical procedures. The optical imaging head can be easily sterilized and integrated into the surgical microscope or robotic arm, meeting the needs of real-time, dynamic intraoperative navigation; the OCT module is placed in a stable area to ensure image quality. This overall architecture fundamentally overcomes the inherent shortcomings of traditional integrated devices in neurosurgical procedures, which are impractical due to their bulkiness, inflexibility, and difficulty in achieving sterilization. It represents the first time that dual-modal imaging navigation technology has been truly applied in neurosurgical procedures. Attached Figure Description

[0026] The present invention can be further illustrated by the non-limiting embodiments given in the accompanying drawings; Figure 1This is a schematic diagram of the optical structure of an embodiment of a dual-modal imaging optical system for navigation in neurosurgery according to the present invention; Figure 2 This is a schematic diagram of the mechanical structure of an embodiment of a dual-modal imaging optical system for navigation in neurosurgery according to the present invention. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present invention, the technical solution of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0028] Example 1 This embodiment provides a dual-modal imaging optical system for navigation in neurosurgery, the optical structure of which is as follows: Figure 1 As shown, the mechanical layout is illustrated in the diagram. Figure 2 As shown. The system adopts a split modular design, mainly composed of an optical head, an OCT module, a robotic arm, and a navigation display. The robotic arm is equipped with optical fibers to connect the optical head and the OCT module.

[0029] The optical head includes a large objective lens group A1. The area in front of the large objective lens group A1 is the surgical area of ​​the brain tissue to be imaged. Behind the large objective lens group A1, a dichroic mirror A2, a beam splitter B1, an illumination lens B2, a homogenizing lens B3, and a light source B4 are arranged coaxially in sequence. The large objective lens group A1, the dichroic mirror A2, the beam splitter B1, the illumination lens B2, the homogenizing lens B3, and the light source B4 form the illumination optical path.

[0030] In the direction of the reflected light path of the beam splitter B1, a front fixed lens B5, a zoom lens B6, a rear fixed lens B7, and an imaging camera B8 are arranged in sequence. The large objective lens group A1, the dichroic mirror A2, the beam splitter B1, the front fixed lens B5, the zoom lens B6, the rear fixed lens B7, and the imaging camera B8 form a color imaging light path.

[0031] In the direction of the reflected light path of the dichroic mirror A2, a three-dimensional galvanometer C1 and a collimator C2 are arranged in sequence to form the spatial scanning and interface part of the OCT beam.

[0032] The OCT module is an independent unit integrated within the optical system. Its core components are connected via optical fiber and mainly include: a first coupler C3, a swept frequency light source C4, a polarization controller C5, a dispersion compensation component C6-1, an optical path compensation component C6-2, a second coupler C7, and a photodetector C8.

[0033] One end of the collimator C2 is connected to the first end of the first coupler C3 via an optical fiber. The second end of the first coupler C3 is connected to the first end of the swept frequency light source C4 and the optical path compensation component C6-2 via optical fibers. The first end of the first coupler C3 is also connected to the first end of the polarization controller C5 via an optical fiber. The second end of the polarization controller C5 is connected to the first end of the dispersion compensation component C6-1 via an optical fiber. The second ends of the dispersion compensation component C6-1 and the optical path compensation component C6-2 are both connected to the first end of the second coupler C7 via optical fibers. The second end of the second coupler C7 is connected to the photodetector C8 via an optical fiber.

[0034] The frequency sweep light source C4, coupler C3, polarization controller C5, dispersion compensation component C6-1, optical path compensation component C6-2, coupler C7, photodetector C8, collimator C2, three-dimensional galvanometer C1, dichroic mirror A2 and large objective lens group A1 in the optical head together form the OCT imaging optical path, which is used to perform high-resolution tomographic scanning of the tissue in the 950nm-1300nm band.

[0035] The illumination optical path and the color imaging optical path share the same large objective lens group A1, dichroic mirror A2, and beam splitter B1.

[0036] The three optical paths mentioned above share the large objective lens group A1 and the dichroic mirror A2, ensuring that the optical axes of all imaging modes are strictly consistent.

[0037] The dichroic mirror A2 is the core component for achieving dual-mode spectral splitting. It transmits visible light in the 300nm-850nm range (for illumination and color imaging) and reflects near-infrared light in the 950nm-1300nm range (for OCT imaging), effectively avoiding crosstalk between wavelengths.

[0038] like Figure 2 As shown, in actual surgical applications, the optical sensor head is detachably mounted on the observation optical path port of the surgical microscope or the end effector of the surgical robot arm via a standardized adapter interface on its housing. The single-mode optical fiber is integrated into the tubing channel of the robotic arm or passes through a dedicated sterile cannula / sealed sleeve, with its other end connected to the OCT module host located in the equipment area of ​​the operating room (usually a non-sterile area). The navigation display is located in a position easily accessible to the surgeon (such as next to the microscope eyepiece or opposite the operating table). This innovative deployment method ensures that the lightweight optical sensor head can move and be positioned freely and flexibly with the microscope or robotic arm within the sterile surgical area, while the larger, vibration-sensitive OCT module host is located away from the surgical operation area. This frees up valuable surgical field space, perfectly meets the stringent sterile environment requirements of neurosurgery, and ensures the stability of OCT imaging.

[0039] The surgeon first observes high-resolution color images of the brain tissue surface, acquired and transmitted in real-time by the optical transducer head, through the eyepiece of the surgical microscope or a navigation display, for macroscopic anatomical structure identification and surgical instrument navigation. When deep exploration of specific areas (such as suspicious tumor boundaries or blood vessel locations) is required, the surgeon can directly mark points of interest on the color image or directly control the robotic arm to align the optical center of the optical transducer head with that point. The system then automatically drives the three-dimensional galvanometer C1 within the optical transducer head, precisely guiding the OCT scanning beam to perform rapid tomographic scanning of the marked area. The photodetector C8 receives the signal and reconstructs the OCT image in real time, instantly displaying it on the navigation display in a picture-in-picture, side-by-side, or transparent overlay manner, synchronously with the color image. The entire process does not require interruption of the surgical procedure or movement or operation of any large, independent equipment, achieving an instantaneous and seamless switch from "macroscopic observation" to "microscopic perspective," providing surgeons with unprecedented real-time, in-situ, multi-scale navigation information.

[0040] Example 2 This embodiment provides a method for the above system to operate in neurosurgical navigation, including the following steps: S1: System Deployment and Surgical Area Preparation Mount the optical sensor head onto the surgical microscope or robotic arm via the adapter interface, ensuring sterility. Connect the single-mode fiber to the OCT module and power on the system. Adjust the microscope or robotic arm to align the optical sensor head with the surgical area, ensuring the brain tissue to be imaged is within the optimal working distance of the large objective lens group A1.

[0041] S2: Surface Color Imaging and Real-time Macro Navigation Turn on the illumination source B4 and the imaging camera B8. The optical head provides uniform illumination, and the visible light reflected from the surgical area is transmitted through the color imaging optical path to form a high-definition color image in real time on the imaging camera B8, which is then displayed on the navigation display. The surgeon can use this to observe macroscopic anatomical structures, locate instruments in real time, and plan the surgical path. During this process, the electrically adjustable zoom lens B6 can be used to continuously magnify and observe specific areas of interest without changing the object distance.

[0042] S3: Target-guided OCT tomography and micro-navigation Guided by real-time color images, doctors use a touchscreen, joystick, or voice commands to pinpoint precise target areas (such as tumor boundaries or blood vessel walls) requiring deep exploration on the monitor. Once confirmed, the OCT imaging scan command is initiated: the system controls the three-dimensional galvanometer C1 to rapidly guide the OCT beam to the target area; near-infrared laser light emitted by the frequency-scanning light source C4 is transmitted via fiber to the collimator C2, where it is converted into spatial light. Through galvanometer scanning and objective lens focusing, high-resolution tomographic scanning of the tissue interior is performed; signal light returning from different depths of the tissue is coupled back to the fiber via its original path and transmitted back to the OCT module, interfering with the reference light; the photodetector C8 receives the interference signal, which is then reconstructed in real-time by the high-speed processing system and immediately displayed on the navigation monitor as cross-sectional, sagittal, or three-dimensional OCT tomographic images of the area.

[0043] S4: Dual-modal information fusion and composite navigation decision-making The system synchronously displays, compares in split screens, or fuses the real-time color image from step S2 with the real-time OCT tomographic image from step S3 on the same navigation interface (e.g., overlaying the outline of key OCT layers onto the color image). Based on this composite navigation information that integrates macroscopic surface information and microscopic deep structure, the surgeon makes precise surgical decisions and operations, such as determining resection boundaries and avoiding important functional areas and blood vessels, thereby significantly improving the accuracy and safety of the surgery.

[0044] The system can simultaneously or fusedly display color images and OCT images, providing doctors with a composite navigation field that combines macroscopic anatomical information and microscopic structural information, greatly improving the accuracy and safety of neurosurgery.

[0045] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A dual modality imaging optical system for neurosurgical navigation, characterized by: This includes a separate optical head and an OCT module connected via single-mode fiber; The optical head includes a large objective lens group (A1), a dichroic mirror (A2), a beam splitter (B1), an illumination lens (B2), a homogenizing lens (B3), a light source (B4), a front fixed lens (B5), a zoom lens (B6), a rear fixed lens (B7), an imaging camera (B8), a three-dimensional galvanometer (C1), and a collimator (C2). The OCT module includes a first coupler (C3), a swept frequency light source (C4), a polarization controller (C5), a dispersion compensation component (C6-1), an optical path compensation component (C6-2), a second coupler (C7), and a photodetector (C8). The illumination light path consists of a large objective lens group (A1), a dichroic mirror (A2), a beam splitter (B1), an illumination lens (B2), a homogenizing lens (B3), and a light source (B4); The color imaging optical path consists of a large objective lens group (A1), a dichroic mirror (A2), a beam splitter (B1), a front fixed lens (B5), a zoom lens (B6), a rear fixed lens (B7), and an imaging camera (B8). The OCT imaging optical route consists of a swept frequency light source (C4), a first coupler (C3), a polarization controller (C5), a dispersion compensation component (C6-1), an optical path compensation component (C6-2), a second coupler (C7), a photodetector (C8), and a collimator (C2), a three-dimensional galvanometer (C1), a dichroic mirror (A2), and a large objective lens group (A1) inside the optical head. The dichroic mirror (A2) transmits visible light in the 300-850nm range and reflects near-infrared light in the 950-1300nm range.

2. The dual modality imaging optical system of claim 1, wherein: The single-mode optical fiber between the optical head and the OCT module is built into the robotic arm that connects the two. The optical head can be detachably installed on the surgical microscope or the robotic arm.

3. The dual modality imaging optical system of claim 1, wherein: The large objective lens group (A1) has a wide band transmission characteristic covering 300-1300nm.

4. The dual modality imaging optical system of claim 1, wherein: The illumination lens (B2) and the uniform light lens (B3) together form a 4F illumination system.

5. The dual modality imaging optical system of claim 1, wherein: The zoom lens (B6) is a movable lens used to continuously adjust the magnification of color imaging without changing the working distance.

6. The dual modality imaging optical system of claim 1, wherein: The OCT module adopts an all-fiber structure and compensates for the system optical path difference and group dispersion through the dispersion compensation component (C6-1) and the optical path compensation component (C6-2).

7. The dual modality imaging optical system of claim 1, wherein: The three-dimensional galvanometer (C1) is located at the back focal plane of the large objective lens group (A1) and is used to scan the OCT beam.

8. The dual-modality imaging optical system of any one of claims 1 to 7, wherein: The system is also connected to a navigation display for synchronously or fusedly displaying the color images acquired by the imaging camera (B8) and the OCT tomographic images reconstructed by the photodetector (C8).

9. A neurosurgical navigation method, characterized by, Using the dual-modal imaging optical system according to any one of claims 1 to 8 includes the following steps: S1: System deployment and surgical area preparation: Install the optical head onto the surgical microscope or robotic arm, complete aseptic processing and connect the system, and adjust the optical head so that the tissue to be imaged is within the working distance of the large objective lens group (A1); S2: Surface color imaging and real-time macro navigation: Turn on the light source (B4) and imaging camera (B8) to acquire and display real-time color images of the surgical area, perform macro navigation, and adjust the zoom lens (B6) to change the magnification. S3: Target-guided OCT tomography and micro-navigation: Under the guidance of color images, the target area for deep exploration is determined, the OCT imaging system is activated, the three-dimensional galvanometer (C1) is controlled to guide the OCT beam to scan the area, and the photodetector (C8) receives the interference signal and reconstructs the OCT tomographic image. S4: Dual-modal information fusion and composite navigation decision-making: Synchronize or fuse color images with OCT tomographic images to provide composite navigation information for surgery.

10. The neurosurgical navigation method of claim 9, wherein, In step S3, points of interest are marked on the color image using a touchscreen, joystick, or voice command to determine the target area.

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