Avoidance of blood vessels in direct selective laser trabecloplasty

Abstract

The disclosure relates to vessel avoidance in direct selective laser trabecloplasty. A system (20) includes a radiation source (48) and a controller (44). The controller is configured to specify a plurality of target areas (84) on an eye (25) of a patient (22) for irradiation with respective amounts of energy, cause the radiation source to irradiate at least a first one of the target areas, identify a change in the eye by processing an image of the eye after causing the radiation source to irradiate at least the first one of the target areas, and determine a change in the eye by processing the image of the eye. And in response to identifying the change, refraining from irradiating a second one of the target regions with the radiation source, the second one of the target regions having not been irradiated with an amount of energy specified for the second one of the target regions. Other embodiments are also described.

Description

[0001] This application is a divisional application of the application filed on October 25, 2021, with application number 202180071581.6 and invention title "Avoiding Blood Vessels in Direct Selective Laser Trabeculoplasty".

[0002] Cross-reference to related applications

[0003] This application is a continuation-in-part of U.S. Application 17 / 136,052, filed December 29, 2020, entitled “Avoiding blood vessels during direct selective laser trabeculoplasty,” the disclosure of which is incorporated herein by reference. This application also claims the benefit of U.S. Provisional Application 63 / 105,388, filed October 26, 2020, entitled “Vasoconstrictors for use in laser eye surgery,” the disclosure of which is incorporated herein by reference. Invention Field

[0004] This invention relates to ophthalmic devices and methods for treating glaucoma, ocular hypertension (OHT), and other diseases. background

[0005] U.S. Patent 5,422,899 describes an optically pumped mid-infrared solid-state laser with a high pulse repetition rate for laser surgery. This laser produces wavelengths from 1.7 micrometers to 4.0 micrometers and is optically pumped.

[0006] U.S. Patent 6,761,713 describes a medical laser unit comprising at least one laser body made of a laser material. A first type of pump source is designed and arranged to continuously excite the laser material and generate continuous laser radiation. A second type of pump source is designed and arranged to pulse the laser material and generate pulsed laser radiation. An emitting unit is designed and arranged to emit both continuous and pulsed laser radiation to the surgical application site. More specifically, the medical laser unit has two operating modes: a first mode for cutting with continuous laser radiation and a second mode for fragmentation using pulsed laser radiation with short durations and high power pulses.

[0007] U.S. Patent 8,160,113 describes an optical system outputting pulses from an optical amplifier having a seed source and an optical amplifier coupled to the seed source, the output of which can be controlled by controlling the power of a seed signal from the seed source. The seed signal can vary between a minimum and a maximum value in such a way that the seed signal presents one or more pulse bursts. Each pulse burst can contain one or more pulses. During the inter-pulse period between consecutive pulses within a pulse burst or between consecutive pulse bursts, the power of the seed signal can be adjusted to an intermediate value greater than the minimum and less than the maximum. This intermediate value is selected to control the gain in the optical amplifier, such that pulses or pulse bursts following this period exhibit the desired behavior.

[0008] U.S. Patent 5,982,789 describes a diode-pumped frequency doubling system that employs a pump diode, crystal, and frequency multiplier in a laser cavity with a diode, and operates with a pulsed or low duty cycle pumping mechanism, while the cavity length is short enough to stabilize the transient response to pulsed diode operation and produce a stable and known or controlled energy output under non-CW pumping mechanisms. In a preferred embodiment, the device employs a frequency multiplier clamped on its noncritical axis and operating together with a control system that generates isotherms in the active mode volume. The controller operates one or more individual heat sources and / or sinks to preheat the diode source or frequency doubling crystal to maintain a directional thermal gradient, and the rate or direction of isotherm migration across the mode volume is controlled according to the upcoming pulse sequence to maintain effectively stable conditions during laser operation. The thermal control system may include an absorber, a heater, and control elements for preheating the laser diode before actuation and during quiet intervals.

[0009] U.S. Patent 5,151,909 describes a laser system using a nonlinear crystal and a solid-state gain medium for second harmonic generation, which operates under the control of a data processor to enable multiple pump power modes. The data processor modulates the pump power in a low-power mode and provides continuous pump power in a high-power mode using a Q-switch. Optionally, modulation can be used in both low-power and high-power modes, with modulation parameters adjusted under program control. Second harmonic generation without a Q-switch can also be achieved in the high-power mode.

[0010] U.S. Patent 6,414,980 describes a method for operating an off-cavity frequency-converted solid-state laser to perform laser processing operations. The laser has a laser resonator comprising an optically pumped gain medium. The resonator is configured to compensate for thermal lensing within a predetermined range in the gain medium. An optical nonlinear crystal located outside the resonator converts the fundamental laser radiation transmitted by the resonator into frequency-converted radiation. The laser processing operation is performed by a pulse sequence of frequency-converted radiation with sufficient power to perform the processing operation. The power of the frequency-converted radiation depends on the transmission parameters of the laser radiation from the laser resonator. The laser operates such that the resonator effectively transmits fundamental laser radiation of the same average power before and during the laser processing operation. This ensures that the thermal lensing effect in the gain medium is within a predetermined range before and during the laser processing operation. The transmission parameters of the laser radiation are varied before and during the processing operation such that the power of the frequency-converted radiation generated before the processing operation is insufficient to perform the laser processing operation.

[0011] In laser trabeculoplasty, a laser uses one or more treatment beams to illuminate the trabecular meshwork in the patient's eye, thereby reducing intraocular pressure. Invention Overview

[0012] According to some embodiments of the present invention, a system is provided comprising a radiation source and a controller. The controller is configured to designate a plurality of target regions on a patient's eye for irradiation with a corresponding amount of energy. The controller is further configured to cause the radiation source to irradiate at least a first target region among the target regions, and is further configured to identify changes in the eye by processing an image of the eye after irradiating at least the first target region among the target regions. The controller is further configured to, in response to identifying a change, suppress irradiation of a second target region among the target regions by the radiation source, the second target region among the target regions having not yet been irradiated with the amount of energy designated for the second target region among the target regions.

[0013] In some embodiments, the controller is configured to suppress the illumination of a second target area within the target area by the radiation source by:

[0014] Specify the new target area, and

[0015] The radiation source is directed to illuminate the new target area instead of the second target area within the target area.

[0016] In some embodiments, the controller is configured to suppress the irradiation of a second target region in the target region with a specified amount of energy by having the radiation source irradiate the second target region in the target region with an energy less than a specified amount.

[0017] In some embodiments, the variation includes bleeding.

[0018] In some embodiments, the change includes swelling.

[0019] In some embodiments, the change includes a change in color.

[0020] In some embodiments, the variation includes forming one or more bubbles.

[0021] In some embodiments, the controller is configured to suppress the radiation source from illuminating the second target area in the target area in response to the distance between the second target area in the target area and another area of ​​the eye.

[0022] In some embodiments,

[0023] The controller is also configured to identify anatomical features at a second target region within the target region, and

[0024] The controller is configured to suppress the radiation source from irradiating a second target area within the target area in response to the identification of anatomical features.

[0025] In some embodiments,

[0026] The controller is also configured to calculate a predicted overlap metric between the radiation beam over a second target region within the irradiated target area and anatomical features, and

[0027] The controller is configured to suppress a second target region within the target region from being irradiated by the radiation source in response to a predicted overlap metric.

[0028] In some embodiments,

[0029] The anatomical features are those of the second target region.

[0030] The controller is also configured to identify the anatomical features of a first target region at a first target region within the target region, and

[0031] The controller is configured to suppress the radiation source from irradiating a second target region within the target region in response to the identification of anatomical features of the first target region.

[0032] In some embodiments, the controller is configured to suppress the radiation source from irradiating the second target region in the target region in response to the first target region anatomical features and the second target region anatomical features being of the same type.

[0033] In some embodiments,

[0034] The controller is also configured to:

[0035] Calculate the estimated overlap metric between (a) the first radiation beam illuminating the first target region within the target area and (b) the anatomical features of the first target region, and

[0036] Calculate the predicted overlap metric between (a) the second radiation beam illuminating the second target region within the target area and (b) the anatomical features of the first target region, and

[0037] The controller is configured to suppress the radiation source from illuminating a second target region in the target region in response to the predicted overlap metric and the estimated overlap metric.

[0038] In some embodiments,

[0039] The controller is also configured to:

[0040] Calculate an estimated amount of energy transmitted from the first radiation beam to the anatomical features of the first target region, and

[0041] Calculate a predicted amount of energy transmitted by the second radiation beam to the anatomical features of the second target region, and

[0042] The controller is configured to suppress the radiation source from irradiating a second target area in the target area in response to a predicted amount of energy and an estimated amount of energy.

[0043] In some embodiments,

[0044] The controller is also configured to calculate a risk metric associated with a second target area within the irradiated target area, and

[0045] The controller is configured to suppress the radiation source from illuminating a second target area within the target area in response to a risk measurement.

[0046] In some embodiments, the controller is configured to calculate risk metrics based on the patient’s medical profile.

[0047] In some embodiments,

[0048] The controller is also configured to identify anatomical features at a second target region within the target region, and

[0049] The controller is configured to calculate a risk metric based on the type of the second anatomical feature.

[0050] According to some embodiments of the present invention, a method is also provided, the method comprising designating a plurality of target regions on a patient's eye for irradiation with a corresponding amount of energy. The method further comprises irradiating at least a first target region among the target regions with a radiation source. The method further comprises, after irradiating at least the first target region among the target regions with a radiation source, identifying changes in the eye by processing an image of the eye. The method further comprises, in response to identifying the changes, suppressing irradiation of a second target region among the target regions, which has not yet been irradiated with the amount of energy designated for the second target region among the target regions.

[0051] According to some embodiments of the present invention, a system is also provided, comprising a radiation source and a controller. The controller is configured to acquire an image of the eye; identify a plurality of edge points in the image, the plurality of edge points being at different corresponding angles relative to a reference point located radially inward from the edge points on the eye, each of the edge points being located on the edge of a corresponding blood vessel; define a plurality of target regions on the eye between the reference point and the edge points; and irradiate the target regions with the radiation source.

[0052] In some embodiments, the reference point is located at the center of the iris of the eye.

[0053] In some embodiments, the reference point is located at the center of the limbus of the eye.

[0054] In some embodiments, the reference point is located at the center of the pupil of the eye.

[0055] In some embodiments, for each angle, the edge of the corresponding blood vessel is closer to the reference point than any other edge of any blood vessel at that angle.

[0056] In some embodiments, the controller is configured to define a target area by:

[0057] Define at least one treatment path between the edge point and the reference point, and

[0058] Define the target area so that each element within the target area is located on the treatment path.

[0059] In some embodiments, the controller is configured to define a treatment path such that the shortest distance between any of the edge points and the treatment path is at least 0.001 mm.

[0060] In some embodiments, the controller is configured to define the treatment path by:

[0061] Define at least one curve that passes through the edge points.

[0062] To shift the curve toward the reference point, and

[0063] The treatment path is defined in response to the offset curve.

[0064] In some embodiments, the controller is configured to respond to the offset curve by defining the treatment path as a perimeter of a predetermined shape tangent within the offset curve.

[0065] In some embodiments, the predetermined shape is an ellipse.

[0066] In some embodiments, the controller is configured to respond to the offset curve defining the treatment path by defining the treatment path as the perimeter of a predetermined shape that is inscribed within the offset curve to the maximum area.

[0067] In some embodiments, the controller is configured to respond to the offset curve defining the treatment path by defining the treatment path as the perimeter of a predetermined shape with the maximum area centered at a reference point and inscribed within the offset curve.

[0068] In some embodiments, the controller is configured to define the treatment path in response to the offset curve by defining the treatment path as a closed curve that is inscribed within the offset curve and has the shape of the corneal limbus of the eye.

[0069] According to some embodiments of the present invention, a method is also provided, the method comprising: acquiring an image of an eye; identifying a plurality of edge points in the image, the plurality of edge points being at different corresponding angles relative to a reference point located radially inward from the edge points on the eye, each of the edge points being located on the edge of a corresponding blood vessel; defining a plurality of target regions on the eye between the reference point and the edge points; and irradiating the target regions with a radiation source.

[0070] According to some embodiments of the present invention, a system is also provided, comprising a radiation source and a controller. The controller is configured to acquire an image of the eye; identify a plurality of edge points in the image, the plurality of edge points being at different corresponding angles relative to a reference point located radially inward from the edge points on the eye, each of the edge points being located on the edge of a corresponding blood vessel; define at least one curve passing through the edge points; and offset the curve toward the reference point. The controller is also configured to receive from a user a definition of a plurality of target regions on the eye when the offset curve is displayed to a user; and to irradiate the target regions with the radiation source.

[0071] According to some embodiments of the present invention, a method is also provided, the method comprising: acquiring an image of an eye; identifying a plurality of edge points in the image, the plurality of edge points being at different corresponding angles relative to a reference point located radially inward from the edge points on the eye, each of the edge points being located on the edge of a corresponding blood vessel; defining at least one curve passing through the edge points; and offsetting the curve toward the reference point. The method further includes receiving from a user the definition of a plurality of target regions on the eye when the offset curve is displayed to a user; and illuminating the target regions with a radiation source.

[0072] According to some embodiments of the present invention, a method is also provided, which includes administering an α2 agonist to a patient's eye and treating the patient's eye with laser radiation within 40 minutes after administering the α2 agonist.

[0073] In some embodiments, treating a patient’s eye includes treating the patient’s eye by irradiating the trabecular mesh of the eye with laser radiation.

[0074] In some embodiments, treating the patient’s eyes includes treating the patient’s eyes within 30 minutes after administration of the α2 agonist.

[0075] In some embodiments, treating a patient’s eye includes treating the patient’s eye in response to an instruction from a controller that the blood vessels in the eye should be sufficiently constricted due to an α2 agonist.

[0076] According to some embodiments of the invention, an α2 agonist is also provided for use in a method of constricting blood vessels in a patient's eye, wherein the α2 agonist is administered to the patient for less than 40 minutes prior to laser radiation therapy of the eye.

[0077] According to some embodiments of the present invention, a system is also provided, comprising a camera and a controller, the camera being configured to acquire images of the eye prior to treating a patient's eye with laser radiation. The controller is configured to calculate a contraction metric by processing the images, the contraction metric indicating the degree to which the blood vessels in the eye constrict due to an α2 agonist. The controller is also configured to output an indication that the blood vessels are sufficiently constricted due to the α2 agonist in response to the contraction metric exceeding a predefined threshold.

[0078] According to some embodiments of the present invention, a system is also provided, comprising a laser and a controller, the laser including a pump source and a laser medium. The controller is configured to designate a plurality of target regions on a patient's eye for sequential irradiation by the laser. The controller is also configured to initiate irradiation of the target regions by driving the pump source to pump the laser medium with a sequence of lasing-causing pulses, each of the lasing-causing pulses being configured to cause the laser medium to emit laser light. The controller is further configured, after initiation of irradiation of the target regions, to replace one of the lasing-causing pulses with one or more heating pulses, the heating pulses being configured to heat the laser medium without causing it to emit laser light.

[0079] In some embodiments, the controller is also configured to heat the laser medium from the pump source before irradiation of the target area begins, without causing the laser medium to emit laser light.

[0080] In some embodiments, the total energy of the heating pulses is between 70% and 100% of the energy of each pulse that induces laser light.

[0081] In some embodiments, one or more heating pulses consist of N>1 heating pulses.

[0082] In some embodiments, each of the heating pulses has a heating pulse duration of D0 / N, where D0 is the lasing pulse duration of each lasing pulse.

[0083] In some embodiments, each of the heating pulses has a peak power equal to the peak power of each of the pulses that cause the laser.

[0084] In some embodiments, the sequence is periodic and has a period T, and the controller is configured to replace the pump source with a heating pulse for a time {k*T / N} from the time of one of the pulses that would otherwise pump to cause laser light, where k=0……N-1.

[0085] In some embodiments, the controller is configured to replace the pump source with a heating pulse in response to a signal indicating an error.

[0086] In some embodiments, the controller is also configured to process one or more images of the eye acquired by the camera, and the controller is configured to replace the pump source with heating pulses in response to processing the images.

[0087] In some embodiments, the controller is configured to identify obstructions to the eye by processing an image, and the controller is configured to replace the pump source with a heating pulse in response to the identification of an obstruction.

[0088] In some embodiments, the controller is configured to identify changes in the eye by processing images, and the controller is configured to replace the pump source with heating pulses in response to identifying the changes.

[0089] In some embodiments, the variation includes forming one or more bubbles.

[0090] In some embodiments,

[0091] The controller is configured to identify the reference point location of a reference point on the eye by processing images.

[0092] The controller is also configured to:

[0093] Based on the reference point location, calculate the location of one of the target regions, and

[0094] Determine where the laser is not aligned with the target area, and

[0095] The controller is configured to replace the pump source with a heating pulse in response to this determination.

[0096] In some embodiments, the system further includes one or more motors, the controller is configured to use the motors to align the laser, and the controller is configured to determine, in response to a corresponding signal from a corresponding encoder of the motor, the location where the laser is not aligned with the target area.

[0097] In some embodiments,

[0098] The laser is a therapeutic laser.

[0099] The system also includes an alignment laser.

[0100] The controller is also configured to:

[0101] To cause the alignment laser to emit an alignment beam at the position aligned with the treatment laser, and

[0102] By processing images, the alignment beam position is identified, and

[0103] The controller is configured to determine where the therapeutic laser is not aligned with the target area based on the displacement between the alignment beam position and the target area position.

[0104] In some embodiments, the wavelength of the aligned beam is greater than 700 nm.

[0105] In some embodiments,

[0106] The images include a first image and a second image. The first image is acquired when the alignment beam is emitted, such that the alignment beam appears in the first image. The second image is acquired before or after the emission of the alignment beam, such that the alignment beam does not appear in the second image.

[0107] The controller is configured to identify the position of the aligned beam in the first image, and

[0108] The controller is configured to identify the location of a reference point in the second image.

[0109] In some embodiments,

[0110] The image consists of a single image including a first frame and a second frame, in which the alignment beam appears, but not in the second frame.

[0111] The controller is configured to identify the position of the aligned beam in the first frame, and

[0112] The controller is configured to identify the location of the reference point in the second frame.

[0113] According to some embodiments of the present invention, a method is also provided, the method comprising designating a plurality of target regions on a patient's eye for sequential irradiation by a laser. The method further comprises initiating irradiation of the target regions by driving a pump source to pump a laser medium with a sequence of laser-inducing pulses, each of the laser-inducing pulses being configured to cause the laser medium to emit laser light. The method further comprises, after initiation of irradiation of the target regions, replacing one of the laser-inducing pulses with one or more heating pulses, the heating pulses being configured to heat the laser medium without causing the laser medium to emit laser light.

[0114] The invention will be more fully understood from the following detailed description of embodiments of the invention taken in conjunction with the accompanying drawings, in which: Brief description of the attached diagram

[0115] Figure 1 This is a schematic diagram of a system for performing trabeculoplasty according to some embodiments of the present invention;

[0116] Figure 2 This is a schematic diagram of a trabeculectomy apparatus according to some embodiments of the present invention;

[0117] Figure 3 This is a schematic diagram of a technique for defining a target area on the eye according to some embodiments of the present invention;

[0118] Figure 4 This is a flowchart of an algorithm for defining a target region according to some embodiments of the present invention;

[0119] Figure 5 This is a flowchart of an algorithm for performing automated trabeculoplasty according to some embodiments of the present invention;

[0120] Figures 6A-6B These are flowcharts of image processing steps according to different corresponding embodiments of the present invention;

[0121] Figure 7 This is a flowchart of the inspection steps according to some embodiments of the present invention;

[0122] Figure 8 The illustrations depict example execution of inspection steps and target region shifting steps according to some embodiments of the present invention; and

[0123] Figure 9 This is a schematic diagram of the timelines of the laser-inducing pulses and heating pulses according to some embodiments of the present invention. Detailed Implementation

[0124] Overview

[0125] When performing laser trabeculoplasty on the eye, it is desirable to avoid irradiating blood vessels and other sensitive anatomical structures due to the risk of bleeding and / or other adverse effects.

[0126] To address this challenge, embodiments of the present invention provide a technique for defining a treatment path that avoids blood vessels in the eye. After defining the treatment path, multiple target regions are defined along the treatment path, and then the target regions are irradiated.

[0127] To define the treatment path, the controller first identifies multiple points on the inner edge of the blood vessels surrounding the limbus of the eye. The controller then defines a curve passing through these points. Next, the controller shifts the curve inwards towards the center of the eye. Finally, the controller inclines the treatment path within the shifted curve.

[0128] Nevertheless, in some cases, such as due to the abnormal distribution of blood vessels in the eye, it may be impossible to define the treatment path as described above. Furthermore, irradiation of sensitive areas outside of blood vessels (such as growths) may also lead to adverse effects.

[0129] Hypothetically, given this challenge, it might be possible to cut off parts of the treatment path that pass through blood vessels and other sensitive areas. However, as the inventors have observed, it is generally not possible to know a priori the eye's sensitivity to radiation; for example, in some patients, even if the laser beam directly hits a blood vessel, it will not cause bleeding. Therefore, for some patients, avoiding all sensitive areas of the eye may unnecessarily reduce the effectiveness of the treatment.

[0130] To address this challenge, embodiments of the present invention allow the treatment path to pass through sensitive areas, but the eye is continuously monitored using appropriate image processing techniques as treatment progresses. If any problematic changes (e.g., hemorrhage) are observed in the eye, for each upcoming target area, the controller assesses the likelihood that irradiation of the upcoming target area will cause similar changes. In response to a high probability, the controller can shift or skip the upcoming target area. Thus, it is advantageous to selectively modify the treatment path without unnecessarily impairing the effectiveness of the treatment.

[0131] For example, in response to observed changes at the irradiated target area, the controller can calculate a risk metric that depends on the type of sensitive anatomical feature at the irradiated target area (if such a feature exists), an estimated amount of radiation energy delivered to that sensitive anatomical feature, the type of sensitive anatomical feature at the upcoming target area (if such a feature exists), and an estimated amount of radiation energy to be delivered to that sensitive anatomical feature. In response to the risk metric exceeding a predefined threshold, the controller can shift or skip the upcoming target area.

[0132] Optionally or additionally, to reduce the amount of bleeding that may occur (e.g., to avoid causing any bleeding), the eye may be treated with a vasoconstrictive α2 agonist (e.g., aclomid and / or brimonidine) before irradiation (e.g., within 40 minutes prior to irradiation). After administration of the α2 agonist, the controller can monitor the degree of vasoconstriction in the eye by processing images of the eye. In response to determining that the blood vessels are sufficiently constricted, the controller can output an indication that irradiation of the eye can begin.

[0133] In addition to monitoring for changes in the eye that indicate a problem, the controller continuously checks for any obstructions along the treatment path using appropriate image processing techniques. In response to the detection of an obstruction, it can shift or skip one or more target areas.

[0134] Typically, taking into account any eye movement after defining the target area, immediately before irradiating each target area, the controller checks whether the laser is aligned with the target area's position. (This check is usually performed in addition to checking for any changes in the eye or obstructions, as described above.) If the laser is not aligned or the position cannot be calculated, the controller aborts the upcoming irradiation. Irradiation of the target area can then be attempted again after acquiring and processing another image of the eye. Optionally, target areas can be skipped.

[0135] To check if the laser is correctly aligned, the controller may process signals received from an encoder of a motor that orients a beam-guiding element used to align the laser. Optionally or additionally, the controller may process images of the eye acquired by a camera to locate the alignment beam that strikes the eye at the position where the laser is aligned. In such embodiments, the alignment beam is invisible to the patient (but visible to the camera), so that the alignment beam does not interfere with the patient. Optionally or additionally, the alignment beam may be configured and / or controlled to not interfere with eye motion tracking. For example, the camera may include a filter matrix that filters the wavelength of the alignment beam, such that the image includes a first frame in which the alignment beam appears and a second frame in which the alignment beam does not appear. Optionally, the controller may acquire a first image when the alignment beam is emitted and a second image when the alignment beam is not emitted. The controller may then locate the alignment beam in the first image or frame, but track eye motion based on the second image or frame.

[0136] In some embodiments, in response to determining that an upcoming irradiation of a target area should be aborted (e.g., due to obstructions, changes such as bleeding, or improper laser alignment), the controller drives the laser pump source to pump the laser medium with one or more heating pulses. Typically, the total energy of the heating pulses is approximately equal to the energy that would otherwise have been delivered to the laser medium if the controller determined that an upcoming irradiation was to occur. However, this total energy is dispersed over a sufficiently long period of time so that the laser medium does not emit laser light. Therefore, it is advantageous that the laser's thermal equilibrium can be maintained until the target area is irradiated (or, if that target area is to be skipped, until the next target area is irradiated). Optionally or additionally, the laser medium can be pumped with heating pulses before treatment begins, such that thermal equilibrium is reached before the first treatment beam is emitted. On the other hand, if the laser medium is not heated for a period of time, the irradiation energy of at least the first treatment beam emitted by the laser after this period may be less than expected, and / or the beam profile or beam alignment may become unstable.

[0137] System Description

[0138] First refer to Figure 1 , Figure 1 This is a schematic diagram of a system 20 for performing trabeculoplasty surgery according to some embodiments of the present invention. The system 20 includes a trabeculoplasty device 21. Also referenced... Figure 2 , Figure 2 This is a schematic diagram of a trabeculectomy apparatus 21 according to some embodiments of the present invention.

[0139] The trabeculoplasty device 21 includes an optical unit 30 and a controller 44. The optical unit 30 includes a radiation source 48 configured to irradiate the patient's eye 25 (e.g., the trabecular mesh of the eye 25) with one or more therapeutic beams 52.

[0140] Typically, the radiation source 48 includes a therapeutic laser 43, such as Ekspla. TM NL204-0.5K-SH laser. The therapeutic laser 43 includes a laser medium 45, which may include, for example, a semiconductor, glass, or crystal, such as a neodymium-doped yttrium aluminum garnet (Nd:YAG) crystal. The laser medium 45 may be pumped by any suitable pump source 47 (e.g., a laser diode). The pump may be optical, electrical, or any other suitable type. The laser 43 also includes a plurality of mirrors 49 arranged to define a stable or unstable resonant cavity. (Each mirror 49 may be an independent element, or it may include a reflective coating applied to another element.) The laser 43 also includes a heat storage unit 57 for removing heat from the laser medium 45.

[0141] In some embodiments, the laser further includes a Q-switch (QS) 63. Optionally or additionally, the laser may include a second harmonic generation (SHG) crystal 51 that converts the wavelength emitted by the laser medium 45 into another wavelength suitable for treatment. (The SHG crystal 51 may be inside or outside the resonant cavity.) The laser may be modified to include an attenuator, a power meter, and / or a mechanical shutter typically located outside the resonant cavity.

[0142] Typically, the radiation source also includes a driver 53, and the controller 44 drives the pump source 47 via the driver 53 to pump the laser medium 45. Specifically, the driver 53 typically receives a control signal 55 from the controller 44 via a cable 59. In response to the control signal 55, the driver outputs an electrical drive signal to the pump source 47, and the pump source responds by pumping the laser medium. In other embodiments, the controller directly drives the pump source by outputting a drive signal to the pump source 47.

[0143] The optical unit 30 also includes one or more beam guiding elements, including, for example, one or more (e.g., two) galvo mirrors 50, which may be collectively referred to as "galvo scanners". Before emitting each treatment beam 52, the controller 44 aligns the treatment laser 43 with the desired target area on the eye 25 by orienting the beam guiding elements to direct the beam toward the target area. (Since each treatment beam is directed onto the eye with a non-infinite spot size, this application generally describes each beam as being directed onto an "area" of the eye rather than a "point" on the eye.) Thus, for example, the beam can be deflected by the galvo mirror 50 toward the beam combiner 56, and then by the beam combiner, such that the beam is directed onto the target area. Thus, the beam follows a path 92 that extends from the downstream end of the optical components in the optical unit 30 (e.g., the beam combiner 56) to the eye 25.

[0144] Typically, the controller orients the beam guide element (and thus aligns it to the laser) by transmitting a control signal 39 (e.g., via cable 23) to a corresponding alignment motor 61 of the beam guide element. Typically, the controller (e.g., via cable 23 or a different cable) receives a feedback signal 37 from a corresponding encoder 67 of the alignment motor 61, which indicates the corresponding orientation of the beam guide element.

[0145] In some embodiments, the treatment beam comprises visible light. Optionally or additionally, the treatment beam may include invisible electromagnetic radiation, such as microwave radiation, infrared radiation, X-ray radiation, gamma radiation, or ultraviolet radiation. Typically, the wavelength of the treatment beam is between 200 nm and 11000 nm, for example, 500 nm–850 nm (such as 520 nm–540 nm, e.g., 532 nm). The spatial profile of each treatment beam 52 on the eye may be elliptical (e.g., circular), square, or any other suitable shape.

[0146] In some embodiments, the radiation source 48 further includes an alignment laser configured to emit a visible or invisible (e.g., infrared) alignment beam. The alignment laser sufficiently overlaps with the treatment laser 43 such that, for any orientation of the beam guiding element, the beam guiding element will direct both the alignment beam and the treatment beam to the same location. Thus, as referenced below... Figure 6B Furthermore, aligning the laser can facilitate the alignment of the treatment laser.

[0147] Alternatively, in addition to a laser, the radiation source may include any other suitable emitter configured to emit a therapeutic beam or a aligning beam.

[0148] The optical unit 30 also includes a camera 54, which the controller 44 uses to acquire images of the eye. Figure 2 As shown, camera 54 is typically at least substantially aligned with path 92; for example, the angle between path 92 and a hypothetical line extending from eye 25 to the camera may be less than 15 degrees. In some embodiments, the camera is positioned behind beam combiner 56 such that the camera receives light via the beam combiner. In other embodiments, the camera is offset relative to the beam combiner.

[0149] Prior to the surgery, camera 54 acquires at least one image of eye 25. (See below for reference.) Figures 3-4 Further described, based on this image, controller 44 can define the target area where the eye will be illuminated. Optionally or additionally, as referenced below. Figures 4-5 Further described, based on the image, controller 44 can identify one or more blood vessels or other anatomical features of the eye.

[0150] Subsequently, during the surgery, camera 54 can acquire multiple images of the patient's eye at a relatively high frequency. Controller 44 can process these images and, in response, control radiation source 48 and beam guiding elements to illuminate the target area of ​​the eye while avoiding obstructions and potentially sensitive anatomical features, as described below. Figures 6A-6B and Figure 7 Further description.

[0151] Typically, camera 54 may include one or more imaging sensors of any suitable type, such as charge-coupled device (CCD) sensors, complementary metal-oxide-semiconductor (CMOS) sensors, optical coherence tomography (OCT) sensors, and / or hyperspectral image sensors. Using these sensors, the camera can acquire any suitable type of two-dimensional or three-dimensional image, such as monochrome images, color images (e.g., based on three-color frames), multispectral images, hyperspectral images, optical coherence tomography (OCT) images, or images generated by fusing multiple images of different corresponding types.

[0152] In some embodiments, the optical unit 30 further includes a light source 66, which is at least substantially aligned with the path 92. For example, the angle between the path 92 and a hypothetical line extending from the end of the path 92 on the eye 25 to the light source 66 may be less than 20 degrees, such as less than 10 degrees. The light source 66 is configured to act as a fixation target 64 by emitting a visible fixation light 68, thereby helping to stabilize the position of the eye.

[0153] Specifically, prior to the surgery, the patient 22 is instructed to fix their eyes 25 relative to the light source 66. Subsequently, during the surgery, the eyes 25 are fixed relative to the light source by means of a fixing light 68 emitted from the light source 66, so that the line of sight of the eyes is approximately aligned with the path 92 (since the light source is approximately aligned with the path) and the eyes are relatively stable. While the eyes are fixed relative to the light source, the radiation source irradiates the eyes with a therapeutic beam 52.

[0154] In some embodiments, the light source 66 includes a light emitter, such as a light-emitting diode (LED). In other embodiments, the light source includes a reflector configured to reflect light emitted from the light emitter.

[0155] Typically, the wavelength of the fixed light 68 (which can be higher or lower than the wavelength of the therapeutic beam) is between 350 nm and 850 nm. For example, the fixed light 68 can be orange or red with a wavelength of 600 nm to 750 nm, while the therapeutic beam can be green with a wavelength of 527 nm to 537 nm.

[0156] Typically, the optical unit includes an optical bench, and at least some of the aforementioned components belonging to the optical unit (e.g., radiation sources, galvanometers, and beam combiners) are coupled to the optical bench. Typically, the optical unit also includes a front surface 33 through which the therapeutic beam and the fixation beam pass. For example, the optical unit 30 may include a housing 31 that at least partially surrounds the optical bench and includes the front surface 33. (The housing 31 may be made of plastic, metal, and / or any other suitable material.) Optionally, the front surface 33 may be attached to the optical bench or may be part of the optical bench.

[0157] In some embodiments, the front surface 33 is shaped to define an opening 58 through which the treatment beam and the fixation beam 52 pass. In other embodiments, the front surface includes an exit window instead of the opening 58, through which the fixation beam 68 and the treatment beam 52 pass. The exit window may be made of plastic, glass, or any other suitable material.

[0158] Typically, the optical unit 30 also includes one or more illumination sources 60, including, for example, one or more LEDs, such as white LEDs or infrared LEDs. For example, the optical unit may include an LED ring surrounding the opening 58. In such an embodiment, the controller 44 can cause the illumination source 60 to intermittently flash light toward the eye, as described in U.S. Patent Application Publication 2021 / 0267800 (the disclosure of which is incorporated herein by reference). This flash can facilitate imaging performed by the camera, and, by means of the brightness of the flash, can further help constrict the pupil of the eye without causing eye damage or patient discomfort. (For ease of illustration, the electrical connection between the controller 44 and the illumination source 60 is not shown in the image.) Figure 2(As clearly shown in the diagram.) In some embodiments, the illumination source 60 is coupled to the front surface 33, such as... Figure 2 As shown.

[0159] To facilitate positioning of the optical unit, the optical unit may include a plurality of beam emitters 62 (including, for example, corresponding laser diodes) configured to direct a plurality of triangulation beams toward the eye, for example, as described in U.S. Patent Application Publication 2021 / 0267800 (the disclosure of which is incorporated herein by reference). In some embodiments, the beam emitters 62 are coupled to the front face 33, such as... Figure 2 As shown. In other embodiments, the beam emitter 62 is directly coupled to the optical bench.

[0160] Optical unit 30 is mounted on XYZ stage unit 32, which is controlled by a control mechanism 36, such as a joystick. Using the control mechanism 36, a user of system 20 (e.g., an ophthalmologist) can position the optical unit before treating the eye (e.g., by adjusting the distance between the optical unit and the eye). In some embodiments, XYZ stage unit 32 includes a locking element configured to prevent movement of the stage unit after it has been positioned.

[0161] In some embodiments, the XYZ motion stage unit 32 includes one or more motors 34, and a control mechanism 36 is connected to an interface circuit 46. When a user manipulates the control mechanism, the interface circuit 46 converts the activity into appropriate electronic signals and outputs these signals to a controller 44. In response to these signals, the controller controls the motors of the XYZ motion stage unit.

[0162] In other embodiments, the XYZ motion stage unit 32 is manually controlled via a manipulation control mechanism. In such embodiments, the XYZ motion stage unit may include a set of gears instead of a motor 34.

[0163] System 20 also includes a headrest 24, which includes a forehead rest 26 and a chin rest 28. During trabeculoplasty, the patient 22 rests his forehead against the forehead rest 26 while placing his chin on the chin rest 28. In some embodiments, the headrest 24 also includes a fixation strap 27 configured to secure the patient's head from behind and thus keep the patient's head pressed against the headrest.

[0164] In some embodiments, such as Figure 1As shown, both the headstock 24 and the XYZ moving stage unit 32 are mounted on a surface 38 (e.g., the top surface of a tray or table). (In some such embodiments, the headstock is L-shaped and attached to the side of the surface 38 rather than the top.) In other embodiments, the XYZ moving stage unit is mounted on the surface 38, while the headstock is attached to the XYZ moving stage unit.

[0165] Typically, such as Figure 1 As shown, when the patient's eyes are illuminated, the optical unit is angled upwards towards the eyes while the eyes are looking downwards, causing path 92 to be tilted. For example, the path can be oriented at an angle θ between five and twenty degrees relative to the horizontal. Advantageously, this orientation reduces the obstruction of the patient's eyes by the upper eyelids and related anatomical structures when the patient's head is positioned against the headrest.

[0166] In some embodiments, such as Figure 1 As shown, the tilt orientation of path 92 is achieved by mounting the optical unit on a wedge 40 (which is mounted on the XYZ moving stage unit). In other words, the optical unit is mounted on the XYZ moving stage unit via the wedge 40. Figure 2 (Wedge part 40 is omitted.)

[0167] Alternatively, or in addition to angulating the optical unit, the patient's head may be tilted back to reduce obstruction to the patient's eyes.

[0168] System 20 also includes a monitor 42 configured to display an image of the eye acquired by the camera. Monitor 42 may be attached to the optical unit 30 or positioned at any other suitable location, such as adjacent to device 21 on surface 38. In some embodiments, monitor 42 includes a touchscreen, and the user inputs commands to the system via the touchscreen. Optionally or additionally, system 20 may include any other suitable input device that can be used by the user, such as a keyboard or mouse.

[0169] In some embodiments, the monitor 42 is directly connected to the controller 44 via a wired or wireless communication interface. In other embodiments, the monitor 42 is connected to the controller 44 via an external processor (e.g., a processor belonging to a standard desktop computer).

[0170] In some embodiments, such as Figure 2 As shown, the controller 44 is located within the XYZ mobile station unit 32. In other embodiments, the controller 44 is located externally to the XYZ mobile station unit. Optionally or additionally, the controller may cooperate with another external processor to perform at least some of the functions described herein.

[0171] In some embodiments, α2 agonist 29 ( Figure 1 The α2 agonist 29 may include, for example, aclomid and / or brimonidine. Typically, the α2 agonist is administered to the eye by instilling eye drops 35 containing an α2 agonist into the eye.

[0172] After administration of α2 agonist 29, the α2 agonist constricts the blood vessels in the eye. After the blood vessels have been sufficiently constricted, the eye is irradiated with a therapeutic beam 52. Typically, the blood vessels are sufficiently constricted, and therefore, irradiation is performed within 40 minutes (e.g., within 30 minutes, 20 minutes, 10 minutes, or 5 minutes) after administration of the α2 agonist.

[0173] In some embodiments, the α2 agonist is administered at least twice. The first administration (e.g., approximately 45-60 minutes before the expected start time of radiation therapy) is to the eye to reduce any possible spikes in intraocular pressure. Subsequently, typically within 40 minutes before the expected start time (e.g., within 30 minutes, 20 minutes, 10 minutes, or 5 minutes), the same or a different α2 agonist is administered. If sufficient contraction is not achieved after the predetermined dose, the same or a different α2 agonist is administered. Treatment is performed after the predetermined dose (typically within 40 minutes, e.g., within 30 minutes, 20 minutes, 10 minutes, or 5 minutes).

[0174] In some embodiments, the user of system 20 can assess whether the blood vessels in the eye are sufficiently constricted without any assistance from controller 44.

[0175] In other embodiments, controller 44 assists the user based on images acquired by camera 54. Specifically, the controller processes the images to calculate a contraction metric indicating the degree of vasoconstriction. (In some embodiments, only the green and / or blue frames of the image are processed for this purpose.) In response to the contraction metric exceeding a predefined threshold, the controller outputs an indication that the blood vessels have sufficiently constricted due to the α2 agonist. For example, the controller may display a message on monitor 42 indicating that radiation therapy can be administered. (The message does not need to explicitly mention contraction.) In response to this indication, the user can begin treatment. Alternatively, if the contraction metric does not exceed the threshold, the controller outputs an indication that the same α2 agonist or a different α2 agonist should be administered.

[0176] In some embodiments, the contraction measure is based on a distance of 86 cm from the limbus of the eye. Figure 3The percentage of pixels with a gray level greater than a predefined threshold (e.g., 230) within a predefined distance. Optionally or additionally, the contraction metric may be based on the number and / or density of detected blood vessels, the average or maximum width of detected blood vessels, and / or any other suitable statistics. To detect blood vessels in an image, the controller can use the following reference... Figure 4 Any technology described.

[0177] In some embodiments, as described herein, at least some functions of controller 44 are implemented in hardware (e.g., using one or more fixed-function or general-purpose integrated circuits, application-specific integrated circuits (ASICs), and / or field-programmable gate arrays (FPGAs). Optionally or additionally, controller 44 may perform at least some of the functions described herein by executing software and / or firmware code. For example, controller 44 may be embodied as a programmed processor including, for example, a central processing unit (CPU) and / or a graphics processing unit (GPU). Program code and / or data, including software programs, may be loaded for execution and processing by the CPU and / or GPU. For example, program code and / or data may be downloaded to the controller electronically via a network. Optionally or additionally, program code and / or data may be provided and / or stored on a non-transitory tangible medium (e.g., magnetic storage, optical storage, or electronic storage). Such program code and / or data, when provided to the controller, create a machine or dedicated computer configured to perform the tasks described herein.

[0178] In some embodiments, the controller includes a system-on-module (SOM), such as Variste. TM DART-MX 8M.

[0179] Target area

[0180] Now for reference Figure 3 , Figure 3 This is a schematic diagram of a technique for defining a target region 84 on an eye 25 according to some embodiments of the present invention.

[0181] Typically, camera 54 ( Figure 2 At least one image 70 of the eye 25 is acquired prior to treatment of the eye. In some embodiments, based on image 70, controller 44 defines a target region 84 such that the target region is not located on any blood vessels 72 visible in the image. (Nevertheless, the target region may be located on blood vessels that are too small or too deep to be visible in the image.)

[0182] To define the target area, the controller first identifies multiple edge points 76 in image 70, each edge point 76 located on the edge of a corresponding blood vessel 72. The edge points 76 are at different corresponding angles relative to a reference point 74 located radially inward on the eye from the edge point. Typically, for each angle, the edge where the edge point is located is closer to the reference point 74 than any other edge of any vessel at that angle. (Usually, at least 50 edge points 76 are identified; however, for simplicity, ...) Figure 3 Only three edge points 76 are shown.

[0183] After identifying the edge points, the controller defines the target region 84 between the reference point and the edge points. (Typically, at least 50 target regions are identified; however, for simplicity, ...) Figure 3 (Only one target region is shown.) For example, the controller may first define at least one treatment path 82 between the edge point and the reference point, and then define the target regions such that each target region lies on the treatment path 82 (e.g., such that the center of each target region lies on the treatment path). Successive target regions can be spaced apart from each other by any suitable angle, such as 2 to 4 degrees. For example, for a 360-degree treatment path, the controller may define 90 to 180 target regions. (Note that, depending on the size of each target region and the spacing angle, successive target regions may overlap.)

[0184] In some embodiments, the controller defines a corresponding edge point and target region for each angle belonging to a predefined set of angles. For angles where the edge of a blood vessel cannot be identified, the controller defines a synthetic edge point that is not actually located at any blood vessel edge, but at a predefined distance from the reference point.

[0185] Typically, the treatment path is defined such that the shortest distance between any edge point and the treatment path is at least 0.1 mm, for example, between 0.1 mm and 1 mm, in order to provide sufficient distance between the target area and the blood vessel.

[0186] In some embodiments, to define the treatment path, the controller first defines at least one curve 78 passing through the edge point 76, for example using any suitable spline interpolation method known in the art. The controller then offsets curve 78 toward the reference point by, for example, a distance between 0.001 mm and 1 mm, to define an offset curve 80. The controller then defines the treatment path in response to the offset curve 80.

[0187] For example, at least a portion of the treatment path may be identical to at least a portion of the offset curve. Alternatively, the treatment path may be defined as the perimeter of a predetermined shape (e.g., an ellipse (e.g., a circle)) inscribed within the offset curve and having any suitable center. For example, the treatment path may be defined as the perimeter of a predetermined shape with the largest area, or the perimeter of a predetermined shape with the largest area centered at reference point 74, inscribed within the offset curve. As yet another option, the treatment path may be defined as a closed curve inscribed within the offset curve and having the shape of the limbus 86 of the eye. As yet another option, the treatment path may be defined by smoothing the offset curve 80 and / or offsetting the offset curve toward the reference point.

[0188] In some cases, such as Figure 3 As shown, the patient's eyelids obscure blood vessels within one or more angular ranges. In this case, the controller typically defines multiple curves 78 (and therefore multiple offset curves 80), each traversing a different angular range of corresponding exposure. Subsequently, based on the offset curves, the controller can define a closed treatment path, as described above. Nevertheless, the controller can suppress defining any target area within the ambiguous angular range (and optionally, a small angular range adjacent to the ambiguous range to provide a safety margin). For example, in Figure 3 In the scenario shown, the controller can suppress [the action / action]. and The area between (assuming the patient's upper eyelid 83 covers the blood vessels within that angle range) defines any target area.

[0189] In other cases, the density of edge points within a specific angular range may be less than the predefined threshold density required by any curve-fitting algorithm used to define curve 78, even if that angular range is exposed. (Low density could be due to an insufficient number of vessels being identified, for example, because the patient is in a state of vasoconstriction.) In this case, the controller can define supplementary points located on the limbus 86 within the angular range to achieve the threshold density. Subsequently, the controller can define curve 78 such that it passes through both the edge points and the supplementary points.

[0190] Typically, after defining the target area, the controller overlays a corresponding marker indicating the target area on image 70. (Optionally, markers indicating treatment paths may also be overlaid on the image.) The controller can then allow the user to adjust any of the target areas as needed, and then indicate to the controller that the target area is approved.

[0191] Optionally or additionally, the controller can perform simulated irradiation of the target area. For example, the controller can transmit control signal 39 to the alignment motor 61 ( Figure 2This allows the treatment laser to be directed sequentially at each target area. The controller can then process data from encoder 67 (…). Figure 2 The controller can send signals to the eye to verify that the laser is actually aligned with each target area. Optionally or additionally, the controller can overlay corresponding markers indicating the laser alignment positions on a real-time image sequence of the eye, allowing the user to verify alignment (including verifying that any eye movements are taken into account). Optionally or additionally, for embodiments where the radiation source includes an alignment laser, the controller can cause the alignment laser to sequentially emit an alignment beam at each target area, as described in U.S. Patent Application Publication 2021 / 0267800 (the disclosure of which is incorporated herein by reference). The controller can then verify that the alignment beam is hitting each target area through image processing. Optionally or additionally, the controller can display a real-time image sequence of the eye where the alignment beam is visible, allowing the user to verify alignment.

[0192] After the user approves the target area and / or the controller and / or the user verify alignment, the controller causes the treatment laser to irradiate the target area.

[0193] Further details regarding the limitations on target region 84 can be found separately here. Figure 4 , Figure 4 This is a flowchart of an algorithm 88 for defining a target region 84 according to some embodiments of the present invention.

[0194] According to Algorithm 88, in the vessel recognition step 90, the controller first identifies the vessels in image 70. To identify vessels, the controller can use segmentation, edge detection, feature enhancement, pattern recognition, and / or any other suitable image processing techniques. For example, these techniques are described in “Sclera recognition—a survey,” Das, Abhijit et al., 2nd IAPR Asia Conference on Pattern Recognition, IEEE, 2013, the contents of which are incorporated herein by reference.

[0195] Subsequently, in the reference point definition step 91, the controller defines a reference point 74. For example, the controller can (e.g., using color segmentation) identify the iris 85 or pupil 87 of the eye, and then place the reference point 74 at the center of the iris 85 or pupil 87. Optionally, the controller can (e.g., using edge detection or maximum gradient detection) identify the limbus 86, and then place the reference point at the center of the limbus. Optionally, when image 70 is displayed on display 41 (… Figure 1When the system is in use, the user of system 20 can indicate the desired location of the reference point using any suitable user interface (e.g., a mouse). In response, the controller can place the reference point at the desired location. The controller can also calculate and store the offset of this location relative to the center of the iris, the center of the pupil, the center of the limbus, or any other anatomical point that can be identified through image processing.

[0196] Subsequently, the controller iterates through multiple angles relative to the reference point. In angle selection step 94, each angle is selected. After selecting an angle, the controller checks in check step 96 whether there are any edge points at the selected angle. (This check is based on the controller having already identified blood vessels in vessel identification step 90.) If so, the controller marks the edge points in edge point marking step 98. Subsequently, or if there are no edge points at the selected angle, the controller checks in another check step 100 whether there are any unselected angles remaining. If so, the controller returns to angle selection step 94.

[0197] Typically, the controller can be selected at any suitable angle. For example, the controller can be positioned relative to any axis (e.g., the horizontal axis, such as...). Figure 3 (As shown) Limit 0 ° Subsequently, during each i-th iteration (where i = 1...M), the controller can choose (i-1)*Δθ, where Δθ can be 0.5. ° 1 ° Or any other suitable value. M is the number of iterations, which can be chosen such that 360 ° It lies between (M-1)*Δθ and M*Δθ.

[0198] After marking the edge points, the controller defines curve 78 in curve definition step 102. Then, in curve offset step 104, the controller offsets curve 78 toward the reference point. Subsequently, in treatment path definition step 106, the controller defines the treatment path based on the offset curve 80. Finally, in target region definition step 108, the controller defines the target region. Typically, each target region is specified as an offset from reference point 74 or any other suitable reference point. (The offset can be specified using a radial coordinate system or a Cartesian coordinate system.)

[0199] In an alternative embodiment, the controller displays the offset curve 80 to the user (by overlaying the offset curve onto image 70, onto another still image of the eye, or onto a live stream of such images), but does not define any target region. Instead, while displaying the offset curve, the controller receives definition of the target region from the user. For example, the user can define the target region by clicking a mouse button at each desired target region location. In response, the controller specifies the treatment laser 43 in sequence ( Figure 2The target area to be irradiated.

[0200] Perform treatment

[0201] Now for reference Figure 5 , Figure 5 This is a flowchart of an algorithm 110 for performing automated trabeculoplasty according to some embodiments of the present invention.

[0202] Algorithm 110 begins with a target region designation step 112, in which the controller designates multiple target regions on the patient's eye for irradiation with corresponding amounts of energy. These corresponding amounts of energy may be the same; alternatively, one or more amounts of energy may differ from the others.

[0203] For example, the controller can be referenced as above. Figures 3-4 The target area is defined as described above. Subsequently, in response to the user's approval of the target area (as referenced above)... Figure 3 (As mentioned above), the controller can specify the target area for irradiation.

[0204] Alternatively, any other technique may be used to specify the target area. For example, see U.S. Patent Application Publication 2021 / 0267800. Figure 3 The disclosure of this U.S. patent application, which allows the user to specify the location of target regions relative to any suitable reference portion of the eye (e.g., the limbus), is incorporated herein by reference. As a specific example, the user can specify an elliptical path for target regions adjacent to the limbus by specifying the number of target regions and the distance from the limbus where the center or edge of each target region will be located. In response to this input, the controller can calculate the location of each target region and, after user approval, designate these regions for irradiation.

[0205] In some embodiments, after specifying the target area, the controller searches for at least a portion of the eye in anatomical feature recognition step 114 to look for any anatomical features that may have enhanced sensitivity to radiation. If blood vessels have not yet been identified, for example in blood vessel recognition step 90 of algorithm 88 (… Figure 4 During this process, such anatomical features may include, for example, blood vessels. Optionally or additionally, such anatomical features may include highly pigmented limbal areas, areas affected by trachoma, localized pemphigoid, localized scleritis, localized burns or other injuries or growths (e.g., pterygium, corneal pannus, arcus senilis, dermoid tumor or any other type of limbal tumor, or limbal pinguecula). Any suitable image processing technique (such as those described above with reference to step 90 of the vessel identification section) may be used to identify sensitive anatomical features.

[0206] In some embodiments, the search for sensitive anatomical features is limited to a distance of 82 from the treatment path ( Figure 3 Within a predefined distance (e.g., 1.5 mm, 3 mm, or 5 mm) of the limbus. In other embodiments, the entire eye is searched.

[0207] Next, the controller selects a first target region in target region selection step 116. Then, the controller begins an iterative treatment process. Each iteration begins with image processing step 117, in which the controller processes one or more images of the eye. (As described in U.S. Patent Application Publication 2021 / 0267800, the controller may flash light to the eye while acquiring one or more images, the contents of which are incorporated herein by reference.) Further reference is now made in this regard. Figure 6A , Figure 6A This is a flowchart of image processing step 117 according to some embodiments of the present invention.

[0208] In some embodiments, image processing step 117 begins with image acquisition step 118, in which camera 54 is used. Figure 2 (To obtain an image of the eye.)

[0209] Subsequently, in the reference point identification step 119, the controller attempts to locate reference point 74 in the image. Figure 3 If the reference point is located, the controller calculates the position of the selected target region based on the location of the reference point in position calculation step 120. For example, if the target region is defined as being at a displacement (dx, dy) from the reference point, and according to the image, the reference point is at (x0, y0), then the controller can calculate the position of the target region as (x0+dx, y0+dy). (The controller thus compensates for any eye movement after target region designation step 112.) On the other hand, if the reference point cannot be located, the controller immediately proceeds to decision step 128 as described below.

[0210] After position calculation step 120, the controller, in alignment start step 125, transmits appropriate control signal 39 to alignment motor 61. Figure 2 ) to activate the treatment laser 43 ( Figure 2The laser is aligned with the selected target area, i.e., the position calculated in alignment position calculation step 120. Subsequently, while the laser is aligned, the controller checks in another inspection step 122 for the presence of any static or dynamic obstructions at the target area. Static obstructions (whose position relative to the eye is constant) may include, for example, growths, such as any of the example growths listed above, or blood vessels on the sclera, limbus, or cornea (e.g., due to corneal neovascularization). Dynamic obstructions (whose position relative to the eye may change during the procedure) may include, for example, eyelids, eyelashes, fingers, or speculum.

[0211] More generally, in the context of this application, including the claims, "block" can be anything other than tissue that the user of the system considers irradiable. Therefore, the scope of the term "block" may vary depending on the procedure. For example, while blood vessels may constitute a block in some procedures, in others irradiation of blood vessels may be acceptable or even desirable, rendering them not a block.

[0212] Typically, any suitable image processing technique can be used to identify obstructions, optionally in conjunction with user input. For example, prior to surgical intervention, a user can indicate one or more parts of the eye that constitute a potential obstruction, for instance, by using image 70 (…). Figure 3 These parts are identified in the process. Subsequently, in inspection step 122, the controller can use template matching, edge detection, or any other suitable technique—including, for example, recognizing changes between successive images—to identify the selected portion of the eye. Such techniques can also be used to identify other static or dynamic obstructions that the user may not have identified beforehand.

[0213] In some embodiments, the controller further checks at check step 122 any obstructions that meet one or more predefined criteria, even if the obstruction does not block the selected target area. For example, the controller may check any obstructions whose size exceeds a predefined threshold or that are moving toward the selected target area.

[0214] If an obstruction is identified, the controller immediately proceeds to decision step 128, where it can determine to suppress the radiation source from irradiating the target area. Otherwise, the controller checks in another check step 124 whether the selected target area is too sensitive to irradiation with a certain amount of energy assigned to the target area, as described below. Figure 7 If the selected target area is too sensitive, the controller immediately proceeds to decision step 128. Otherwise, the controller checks in another check step 127 whether the laser is properly aligned, i.e., whether the laser is aligned with the position of the target area. For example, the controller can process data from encoder 67 (…). Figure 2Feedback signal 37.

[0215] If the laser is improperly aligned, the controller immediately proceeds to decision step 128. Otherwise, in some embodiments, the controller performs one or more final verifications in verification step 135. (Optionally, any of these verifications may be performed at an earlier stage of image processing step 117.) For example, as described in U.S. Patent Application Publication 2021 / 0267800 (the disclosure of which is incorporated herein by reference), the controller may verify that the target area is not located (or even partially located) in a predefined “no-go zone,” which is a static area in the camera’s field of view (FOV) where illumination is prohibited for safety reasons. Optionally or additionally, as further described in U.S. Patent Application Publication 2021 / 0267800, the controller may verify that the target area is within a predefined distance from the previously identified target area, indicating that the eye is relatively stationary. After performing verification step 135, the controller performs decision step 128.

[0216] In determination step 128, the controller, in response to processing the image of the eye in image processing step 117, determines whether to illuminate the selected target area. If, for example, the reference point is locatable, no obstructions are identified, the selected target area is not too sensitive, the laser is properly aligned, and verification step 135 is successfully performed, the controller can determine that the selected target area should be illuminated.

[0217] After determining that irradiation should proceed, the target area is irradiated with a treatment beam in irradiation step 130. Subsequently, the controller checks in another check step 132 whether there are any other target areas that have not yet been selected. If so, the controller selects the next target area in another target area selection step 133, and then begins the next treatment iteration by returning to image processing step 117. Otherwise, the treatment process ends.

[0218] On the other hand, if the controller determines that the selected area should not be illuminated, the controller, for example, transmits an appropriate control signal 55 to the driver 53. Figure 2 In heating start step 129, heating of the laser medium 45 is initiated. (See below for reference) Figure 9 (Further described, the laser medium does not emit laser light in response to heating.) Subsequently, when the laser medium is heated, the controller determines in another decision step 131 whether to skip the selected target area, that is, to suppress irradiation of the selected target area even in subsequent iterations. For example, if an obstruction is detected at the location of the target area or the target area is too sensitive, the controller may decide to skip the selected target area.

[0219] If the controller determines to skip the target area, it proceeds to check step 132. Otherwise, the controller determines in another decision step 137 whether to move the selected target area. For example, if an obstruction is detected at the location of the target area, or if the current location of the target area is too sensitive to illumination, the controller may determine to move the selected target area.

[0220] If the controller determines to shift the target area (e.g., to avoid identified obstructions), the controller shifts the target area in target area shift step 126. (Typically, the target area is shifted away from the pupil, not towards it.) The controller then returns to image processing step 117. Therefore, during subsequent iterations, the controller can cause the radiation source to illuminate a different location than the original location of the target area.

[0221] On the other hand, if the controller determines that the target area has not been shifted, the controller immediately returns to image processing step 117. Therefore, the original position of the target area can be illuminated during subsequent iterations.

[0222] In other embodiments, if an obstruction or target area is identified as being too sensitive to irradiation with a specified amount of energy, the controller can (after performing alignment initiation step 125, check step 127, and verification step 135) determine to irradiate the target area with a certain amount of energy less than the specified amount. To control the energy of the treatment beam 52, the controller can control the energy pumped to the laser medium 45 ( Figure 2 The amount of energy.

[0223] Optionally, the controller can completely terminate the treatment procedure if an obstruction is detected or the target area is too sensitive.

[0224] In some embodiments, for greater efficiency, calculation step 120 and alignment initiation step 125 are performed prior to reference point identification step 119, based on the reference point's position during previous iterations. In such an embodiment, after identifying the reference point's position, the controller checks that the reference point has not moved beyond a predetermined threshold amount. If the reference point has not moved beyond the threshold amount, the controller executes subsequent steps of image processing step 117.

[0225] Now for reference Figure 6B , Figure 6B This is a flowchart of image processing step 117 according to another embodiment of the present invention.

[0226] As referenced above Figure 2In some embodiments, the optical unit 30 includes an alignment laser. In such an embodiment, after the two lasers are aligned to a calculated position in the target area, the controller causes the alignment laser to emit an alignment beam. The controller then processes an image of the eye to identify the position of the alignment beam on the eye and calculates the displacement between that position and the calculated position of the target area. The controller can then determine that the treatment laser is improperly aligned based on this displacement. For example, the controller can determine that the treatment laser is improperly aligned in response to the displacement exceeding a predefined threshold.

[0227] For example, such as Figure 6B As shown, in some embodiments, after calculation step 120 calculates the position of the selected target area, the controller initiates alignment of the alignment laser and the treatment laser at the calculated positions of the selected target area in another alignment initiation step 162. (e.g.) Figure 6B As assumed in the calculation, the calculation can be based on the position of a reference point during previous iterations. After laser alignment, the controller causes the alignment laser to emit an alignment beam in emission step 164. (Optionally, the alignment beam can be emitted continuously during the procedure.) In some embodiments, the wavelength of the alignment beam is greater than 700 nm (i.e., the alignment beam is infrared), making the alignment beam invisible to the patient and therefore not disturbing.

[0228] Next, the controller acquires at least one image of the eye. For example, such as Figure 6B As assumed in the text, the controller can acquire a single image while emitting the alignment beam, the single image including a first frame in which the alignment beam appears and a second frame in which the alignment beam does not appear. For example, camera 54 ( Figure 2 This can include a filter matrix (or "filter array") configured to filter the alignment beam from the second frame. For example, in an embodiment where the wavelength of the alignment beam is greater than 700 nm, the filter matrix can filter out wavelengths greater than 700 nm. Optionally, the wavelength of the alignment beam can be selected such that a standard Bayer filter filters out the alignment beam from the second frame. For example, the alignment beam can be red, making it visible in the first (red) frame of the image but not in the second (green) frame.

[0229] Subsequently, in the alignment beam positioning step 166, the controller attempts to position the alignment beam in the first frame of the image. If the alignment beam cannot be positioned, the controller immediately proceeds to the decision step 128. Otherwise, in the reference point positioning step 168, the controller attempts to position a reference point in the second frame of the image. If the reference point cannot be positioned, the controller immediately proceeds to the decision step 128. Otherwise, the controller proceeds to the check step 127, in which the controller checks (i) whether the alignment beam is hitting the calculated position of the target area, and (ii) whether the displacement between the current position of the reference point and the position of the reference point during the previous iteration is less than a predefined threshold. If not, the controller immediately proceeds to the decision step 128. Otherwise, the controller executes the check steps 122, 124, and 135.

[0230] In other embodiments, the controller acquires two images of the eye: a first image and a second image. The first image is acquired when the alignment beam is emitted, such that the alignment beam appears in the first image (as described above); the second image is acquired before or after the alignment beam is emitted, such that the alignment beam does not appear in the second image. For example, after acquiring the first image, the controller may turn off the alignment beam and then acquire the second image. The controller may then attempt to locate the alignment beam in the first image at alignment beam positioning step 166 and attempt to locate a reference point in the second image at reference point positioning step 168.

[0231] In other embodiments, the controller acquires a single image and locates the alignment beam and reference point within the same frame of the image.

[0232] Now for reference Figure 7 , Figure 7 This is a flowchart for checking step 124 according to some embodiments of the present invention.

[0233] The inspection step 124 begins with the first evaluation step 134, in which the controller processes the most recently acquired image, typically along with previously acquired images, to determine if any problematic changes have occurred in the eye—such as hemorrhage, swelling, changes in the density of identifiable blood vessels, the formation of one or more bubbles, and / or changes in color. If no such changes are identified, the controller determines that the selected target area is not too sensitive to irradiation. Otherwise, as further described below, the controller may determine that the selected target area is too sensitive to irradiation.

[0234] During the execution of the first evaluation step 134, the controller may use any suitable image processing techniques, including, for example, optical flow, pattern recognition, edge detection, segmentation, differential checks, and / or color monitoring. For instance, the controller may use pattern recognition to align the latest image with previously acquired images (e.g., images acquired prior to the treatment procedure), thereby facilitating alignment. Subsequently, the controller may subtract the previously acquired image from the current image and then use edge detection or segmentation to identify the location of any features of interest (e.g., color variations or other features indicating bleeding or swelling) in the difference image.

[0235] In response to the identification of the problematic change, the controller determines (in the second evaluation step 136) Figure 5 The anatomical feature identification step 114 identifies whether any sensitive anatomical feature is located within the selected target region. In the context of this application, including the claims, an anatomical feature is said to be located within the target region if any portion of the anatomical feature is within a predefined threshold distance of the target region. The threshold distance is typically defined automatically or semi-automatically based on: (i) the eye's position during image acquisition step 118 ( Figures 6A-6B ) and irradiation step 130 ( Figure 5 (ii) the maximum possible movement between (i) and (ii) the calibration accuracy of the laser. In some embodiments, the predefined threshold distance is less than 3 mm.

[0236] In response to a sensitive anatomical feature being located in the selected target region, the controller calculates a predicted overlap metric between the treatment beam irradiating the selected target region and the anatomical feature in overlap prediction step 138. The predicted overlap metric can be expressed, for example, as the amount of area of ​​the anatomical feature predicted to overlap with the beam.

[0237] When calculating the predicted overlap metric, the controller may assume that the treatment beam does not deviate from the target area. Optionally, prior to surgery, the controller may calculate a probability distribution of the deviation between the treatment beam and the target area, and / or one or more statistical data points of that distribution, such as maximum deviation, average deviation, or median deviation. Subsequently, the controller may calculate the predicted overlap metric based on these statistical data, for example, by assuming that the treatment beam deviates from the anatomical feature by the maximum, average, or median deviation.

[0238] Subsequently, or if no sensitive anatomical feature is present at the selected target area, the controller determines in the third evaluation step 140 whether the change identified in the first evaluation step 134 could be due to irradiation of a sensitive anatomical feature at any of the irradiated target areas. For example, the controller may check whether any portion of the image showing the change is within a predefined threshold distance of such a sensitive anatomical feature.

[0239] If the change is likely due to irradiation of a sensitive anatomical feature, the controller calculates an estimated overlap metric between the treatment beam and the anatomical feature in the irradiated target area in overlap estimation step 142. The estimated overlap metric can be expressed, for example, as the amount of area of ​​the anatomical feature that is estimated to have overlapped with the beam. After calculating the estimated overlap metric, or if the change is likely not due to irradiation of a sensitive anatomical feature, the controller performs a risk metric calculation step 144, as described below.

[0240] In some embodiments, the controller is based on the alignment beam positioning step 166 ( Figure 6B The controller estimates the overlap of the position of the aligned beam identified. For example, the controller may assume that the treatment beam is positioned at (i) the location of the aligned beam in an image acquired immediately before the emission of the treatment beam, or (ii) the location of the aligned beam in an image acquired immediately after the emission of the treatment beam. Optionally, the controller may calculate the average of (i) and (ii) and assume that the treatment beam is emitted onto the eye at that average location.

[0241] Alternatively, in embodiments where no alignment beam is emitted, the controller may estimate the overlap metric based on the position where the treatment laser is aligned (as indicated by feedback signals from the encoder) and the estimated spot size of the treatment beam on the eye.

[0242] In addition to estimating and predicting the overlap metric, the controller can calculate an estimated amount of energy (from the treatment beam) delivered to a sensitive anatomical feature at the irradiated target area, and a predicted amount of energy (from the treatment beam) delivered to a sensitive anatomical feature at a selected target area. Typically, the estimated amount of delivered energy or the predicted amount of delivered energy is a function of the estimated overlap metric or the predicted overlap metric, and varies with system 20 ( Figure 1 The parameters vary depending on the settings (e.g., the energy and spot size of the treatment beam).

[0243] In risk metric calculation step 144, the controller calculates a risk metric associated with irradiating the selected target region. Typically, the risk metric is greater if a sensitive anatomical feature is present in the selected target region, compared to the case where no sensitive anatomical feature is present. Furthermore, the risk metric is an increasing function of the predicted amount with respect to the selected target region, because a higher overlap metric, or the amount of energy delivered, is more likely to cause another change in the eye. Conversely, generally, the risk metric is greater if the identified change is unlikely to be due to irradiation of a sensitive anatomical feature and is a decreasing function of the estimated amount. Thus, for example, the risk metric could be an increasing function of the ratio of the predicted amount to the estimated amount.

[0244] Optionally or additionally, risk measures can be based on the patient's medical profile, particularly those aspects related to the patient's eye sensitivity. For example, risk measures can be based on parameters such as the patient's age, sex, medication history (especially regarding the use of topical ocular medications), frequency of contact lens use, and / or intraocular pressure. Thus, for example, a higher risk measure can be calculated for a patient with a history of topical ocular medication use compared to other patients without such a history.

[0245] Optionally or additionally, the risk measure can be based on the type of anatomical feature at the selected target region. For example, larger vessels may be known a priori to have a greater chance of bleeding than smaller vessels; therefore, the risk measure for larger vessels is higher than that for smaller vessels.

[0246] Optionally or additionally, the risk metric may be an increasing function of the similarity between anatomical features at the selected target region and irradiated anatomical features identified in the third assessment step 140. Similarity may include, for example, similarity in type, color, and / or size.

[0247] Optionally or additionally, the risk measure may be based on the type of change identified; for example, the risk measure in response to detecting bleeding or swelling may be higher than that in response to detecting only a change in color.

[0248] After calculating the risk metric, the controller compares the risk metric with a predefined threshold in the fourth evaluation step 146. If the risk metric exceeds the threshold, the controller determines that the selected target area is too sensitive to irradiation. In response, the controller may suppress irradiation of the target area, or at least reduce the energy irradiated into the target area, as referenced above. Figure 5 As stated above.

[0249] In cases where one or more identified variations may be caused by irradiation of multiple sensitive anatomical features, the controller considers each of these anatomical features when assessing the risk to the selected target region. For example, the risk metric may be based on the corresponding type of the sensitive anatomical feature and / or the corresponding estimated overlap metric of the sensitive anatomical features.

[0250] Notice, Figure 7 The flowchart is presented by way of example only, and many other embodiments of checking step 124 are included within the scope of this invention. For example:

[0251] (i) Optionally, or in addition to determining whether a sensitive anatomical feature exists at the selected target region, the controller may determine whether the selected target region is within a predefined threshold distance of a sensitive area of ​​the eye (e.g., pupil or vascular convergence). If so, a risk metric may be added, optionally as a function of the distance between the target region and the sensitive area.

[0252] (ii) In response to the identification of a problematic change, the controller may acquire and process additional images before proceeding to the remainder of inspection step 124. Processing of the additional images may allow the controller to verify the change, identify the type of change, and / or monitor the change for safety purposes. Thus, for example, if bleeding does not stop within a predetermined duration, or if the area covered by blood exceeds a predefined threshold, the treatment procedure may be terminated.

[0253] (iii) Even without calculating a risk metric, the controller can determine that the selected target area is too sensitive to irradiation. For example, this determination can be made immediately after the presence of a sensitive anatomical feature is identified in the second assessment step 136. Alternatively, such a determination can be made in response to a predicted overlap metric exceeding a predefined threshold or a predicted amount of transfer energy, which can be an absolute number or a number derived from an estimate of the corresponding irradiated target area identified in the third assessment step 140. Alternatively, such a determination can be made in response to the sensitive anatomical feature at the selected target area and the irradiated anatomical feature being of the same type.

[0254] Now for reference Figure 8 , Figure 8 The inspection step 124 according to some embodiments of the present invention is illustrated in the figure. Figures 6A-6B ) and target area shifting step 126 ( Figure 5 Example execution.

[0255] Figure 8 Image 148 of eye 25 acquired in image acquisition step 118 is shown. Figures 6A-6B ). By referring to the first evaluation step 134 of the inspection step 124 as described above ( Figure 7 By processing image 148, the controller can identify a blood pool 150 near the irradiated target area 84a. The blood pool 150 indicates that irradiation of the target area 84a may cause bleeding in the first blood vessel 72a located at the target area 84a. Therefore, before irradiating another target area 84b, the controller can reposition the target area 84b away from the second blood vessel 72b, thereby reducing the likelihood of another bleeding event.

[0256] Heating Pulse

[0257] Refer again Figure 2 And also refer to Figure 9 , Figure 9 This is a schematic diagram of the timelines of the laser-inducing pulse 152 and the heating pulse 154 according to some embodiments of the present invention.

[0258] Typically, in (for example, according to) Figure 5Before the algorithm 110 begins irradiating the target area, the controller 44 (e.g., via the control driver 53) causes the pump source 47 to heat the laser medium 45 without causing the laser medium to emit laser light. For example, the controller can cause the pump source to pump the laser medium with a sequence 156 of one or more heating pulses 154, which will be further described below. As a result of this heating, the laser medium can reach thermal equilibrium before emitting any processed beam.

[0259] To initiate irradiation of the target area, a controller (e.g., via control driver 53) drives a pump source to begin pumping the laser medium 45 with a sequence 158 of laser-inducing pulses 152. Typically, the sequence 158 is periodic and has a period T, meaning that each laser-inducing pulse 152 (except for any laser-inducing pulses following the heating pulse 154) occurs at an interval T from the previous laser-inducing pulse. Each laser-inducing pulse 152 causes the laser medium to emit laser light, and thus emits light near the end of the pulse (as shown in the image). Figure 9 The treatment beam 52 (indicated by laser marker 160) is located in the center. Figure 5 The irradiation step 130 includes pumping the laser medium with a laser-inducing pulse and emitting a therapeutic beam.

[0260] After irradiation of the target area begins, the controller can replace one of the pulses that cause laser emission with one or more heating pulses 154 from the pump source. Each heating pulse 154 is configured to heat the laser medium without causing the laser medium to emit laser light.

[0261] For example, as referenced above Figure 5 and Figures 6A-6B The controller can process (e.g., in image acquisition step 118) one or more images of the eye acquired by camera 54, and in response to processing the images, replace the pump source with heating pulses. For example, the controller can replace the pump source with heating pulses in response to (in inspection step 122) identifying an obstruction in the eye, (in inspection step 124) identifying a change in the eye, or (in inspection step 127) determining that the therapeutic laser is not aligned with the target area to be irradiated. Optionally, the controller can replace the pump source with heating pulses in response to a signal indicating an error. For example, feedback signal 37 ( Figure 2 This can indicate that the beam guiding element is not oriented as expected, or another signal can indicate a malfunction in any other component of the treatment laser or optical unit.

[0262] Typically, the total energy E2 of the heating pulse that replaces the pulse that causes the laser is approximately equal to the energy E0 of the pulse that causes the laser, minus the energy E1 lost by the laser medium during laser emission. Therefore, the thermal equilibrium of the laser medium is maintained. Typically, E1 is between 0% and 30% of E0, such that E2 is between 70% and 100% of E0.

[0263] For example, the pump source can be replaced by a single heating pulse that propagates energy E2 over a sufficiently long duration, such that the threshold for the laser medium to emit laser light is not reached.

[0264] Alternatively, the pump source can be replaced by N>1 heating pulses. For example, assuming the duration of each laser-inducing pulse is D0 (where D0 is, for example, between 120 and 150 microseconds), each heating pulse can have a duration D0, but lower than the average power of each laser-inducing pulse, such that the energy of the heating pulse is E2 / N. Alternatively, each heating pulse can have a duration of D0 / N. For example, each heating pulse can have a duration of D0 / N and a peak power equal to the peak power of each laser-inducing pulse. As a concrete example, assuming the instantaneous power of each laser-inducing pulse is approximately constant at P0 = E0 / D0, each heating pulse can have a duration D0 / N and an instantaneous power approximately constant at P0, such as... Figure 9 The figure shows N=2.

[0265] Typically, the time {k*T / N} from the time t0 when the laser-inducing pulse has been pumped is replaced by a heating pulse, where k = 0…N-1. For example, as… Figure 9 As shown, for N=2, the first heating pulse can start at t0, and the second heating pulse can start at t0+T / 2.

[0266] Although the above description primarily relates to trabeculoplasty, it should be noted that embodiments of the invention can be applied to any type of surgery in which the target area of ​​the eye is irradiated, such as transscleral cyclophotocoagulation (TSCPC) or tissue shrinkage.

[0267] Those skilled in the art will recognize that the present invention is not limited to what has been specifically shown and described above. Rather, the scope of embodiments of the invention includes combinations and sub-combinations of the various features described above, as well as variations and modifications thereof that would occur to those skilled in the art upon reading the above description and that are not found in the prior art. Documents incorporated herein by reference are considered part of this application, and the definitions in this specification should be considered only, unless any terms are defined in these incorporated documents in a manner that conflicts to some extent with the definitions expressly or implicitly made herein.

Claims

1. A system comprising: A laser, which includes a pump source and a laser medium; as well as The controller is configured to: Multiple target areas are designated on the patient's eye for sequential irradiation by the laser. Irradiation of the target region begins by driving the pump source to pump the laser medium with a sequence of laser-inducing pulses, each of which is configured to cause the laser medium to emit laser light. After the target area is irradiated, the pump source is replaced with one or more heating pulses that induce laser light, the heating pulses being configured to heat the laser medium without causing the laser medium to emit laser light.

2. The system according to claim 1, wherein, The controller is also configured to heat the laser medium with the pump source before irradiation of the target area begins, without causing the laser medium to emit laser light.

3. The system according to claim 1, wherein, The total energy of the heating pulses is between 70% and 100% of the energy of each of the laser-inducing pulses.

4. The system according to any one of claims 1-3, wherein, The one or more heating pulses consist of N>1 heating pulses.

5. The system according to claim 4, wherein, Each of the heating pulses has a heating pulse duration of D0 / N, where D0 is the laser-inducing pulse duration of each of the laser-inducing pulses.

6. The system according to claim 5, wherein, Each of the heating pulses has a peak power equal to the peak power of each of the pulses that induce the laser.

7. The system according to claim 4, wherein, The sequence is periodic and has a period T, and the controller is configured to replace the pump source with the heating pulse at a time {k*T / N} from the time when it should have pumped one of the laser-inducing pulses, where k=0……N-1.

8. The system according to any one of claims 1-3, wherein, The controller is configured to replace the pump source with the heating pulse in response to a signal indicating an error.

9. The system according to any one of claims 1-3, wherein, The controller is also configured to process one or more images of the eye acquired by the camera, and wherein the controller is configured to replace the pump source with the heating pulse in response to processing the images.

10. The system according to claim 9, wherein, The controller is configured to identify obstructions to the eye by processing the image, and wherein the controller is configured to replace the pump source with the heating pulse in response to identifying the obstruction.

11. The system according to claim 9, wherein, The controller is configured to identify changes in the eye by processing the image, and wherein the controller is configured to replace the pump source with the heating pulse in response to identifying the changes.

12. The system according to claim 11, wherein, The changes include the formation of one or more bubbles.

13. The system according to claim 9, in, The controller is configured to identify the reference point location of the reference point on the eye by processing the image. The controller is further configured to: Based on the location of the reference point, calculate the location of one of the target regions, and Determining that the laser is not aligned with the target area, and The controller is configured to replace the pump source with the heating pulse in response to the determination.

14. The system of claim 13, further comprising one or more motors, wherein, The controller is also configured to use the motor to align the laser, and wherein the controller is configured to determine, in response to a corresponding signal from a corresponding encoder of the motor, that the laser is not aligned with the target area.

15. The system according to claim 13, in, The laser in question is a therapeutic laser. The system also includes an alignment laser. The controller is further configured to: The alignment laser emits an alignment beam at the position aligned with the treatment laser, and The alignment beam position is identified by processing the image, and The controller is configured to determine the location where the therapeutic laser is not aligned with the target area based on the displacement between the alignment beam position and the target area position.

16. The system according to claim 15, wherein, The wavelength of the alignment beam is greater than 700 nm.

17. The system according to claim 15, in, The images include a first image and a second image. The first image is acquired when the alignment beam is emitted, such that the alignment beam appears in the first image. The second image is acquired before or after the emission of the alignment beam, such that the alignment beam does not appear in the second image. The controller is configured to identify the position of the aligned beam in the first image, and The controller is configured to identify the location of the reference point in the second image.

18. The system according to claim 15, in, The image consists of a single image including a first frame and a second frame, in which the alignment beam appears, and in which the alignment beam does not appear, in the second frame. The controller is configured to identify the position of the aligned beam in the first frame, and The controller is configured to identify the location of the reference point in the second frame.

Images