Patent Publication Number: US-2023141098-A1

Title: Method and apparatus for performing ophthalmic procedures removing undesirable features using laser energy

Description:
FIELD 
     This present disclosure relates generally ophthalmic surgery and, more particularly, to a method and apparatus for performing ophthalmic procedures removing undesirable features using laser energy. 
     BACKGROUND 
     The human eye sees by transmitting and refracting light through a clear outer portion of the eye called the cornea, transmitting the light through an aperture in the iris known as the pupil, focusing the light via a lens, transmitting the focused light through the vitreal cavity and onto the retina. The quality of the focused image depends on many factors including but not limited to the size, shape and length of the eye, the quality of the vitreous humor, and the shape and transparency of the cornea and lens. Trauma, age, disease and/or another malady may cause an individual&#39;s vision to degrade. 
     For example, undesirable features within the vitreal cavity may adversely vision. Vitreous opacities, otherwise known as vitreous floaters, are one type of undesirable feature. Vitreous opacities are free to move within the vitreous humor of the vitreal cavity. When sufficiently large and/or dense and within the optical path between the pupil and the retina, such vitreous opacities may obscure an individual&#39;s vision. One remedy for vitreous opacities is removal. In some cases, a small gauge vitrectomy may be performed. The small gauge vitrectomy may be performed by inserting a narrow gauge line into the vitreal cavity and removing a portion of the vitreous humor containing the vitreous opacity. Alternatively, the vitreous opacity may be removed via the application of laser energy. In such a method, a physician uses a slit lamp to view the posterior portion of the eye and localize the vitreous opacities. The physician then manually aims and fires the laser. The laser energy vaporizes at least part of a vitreous opacity. This procedure is repeated until the vitreous opacity is removed. The entire procedure is repeated for each vitreous opacity, until the vitreal fluid is deemed sufficiently clear. 
     Although the vitreous floaters may be removed, there are drawbacks. Small gauge vitrectomies are invasive, require an operating visit and carry the attendant risks. The use of laser energy is non-invasive and avoids these drawbacks. However, aiming of the laser may be difficult. Because the physician views the vitreal cavity along the optical path, it may be difficult to determine the depth of the location of the retina, the vitreous opacity or other relevant features. Consequently, there is a danger of missing the vitreous opacity and/or injuring the eye. Application of laser energy may also result in movement of the vitreous opacities. Thus, the physician re-aims the laser after each application of laser energy. This may consume a large amount of time. Therefore, the use of laser energy may involve multiple out-patient visits, each of which may be hours long. Such a procedure is burdensome on the patient and the physician. 
     Accordingly, what is needed is a mechanism for improving the removal of undesirable features in the vitreal cavity. 
     BRIEF SUMMARY OF THE INVENTION 
     A method and system perform an ophthalmic procedure on an eye having an optical path from the lens to the retina. An image of at least part of the eye is received in a data processing unit. The image includes the optical path. The data processing unit determines keep out zone(s) and identifies undesirable feature(s) based on the image. The keep out zone(s) include the retina. The data processing unit also selects one of the undesirable feature(s) for removal. At least part of the undesirable feature is outside of the keep out zone(s). Confirmation for removal of the undesirable feature is received in the data processing unit. In response to receiving the confirmation, a control unit controls a laser to perform laser removal the at least the portion of the undesirable feature without targeting any portion of the keep out zone(s). 
     According to the method and system disclosed herein, a physician may be better and more easily able to remove undesirable features such as vitreous opacities without surgery. 
    
    
     
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
       For a more complete understanding of the present disclosure and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numerals indicate like features and wherein: 
         FIG.  1    is a flow chart depicting an exemplary embodiment of a method for performing an ophthalmic procedure that removes undesirable features using laser energy; 
         FIG.  2    is a block diagram of an exemplary embodiment of an ophthalmic laser apparatus for removing undesirable features from the vitreal cavity using laser energy; 
         FIG.  3    is a flow chart depicting an exemplary embodiment of a method for performing an ophthalmic procedure removing undesirable features such as vitreous opacities using laser energy; and 
         FIGS.  4 A- 4 L  depict exemplary embodiments of images of the eye during non-surgical removal of undesirable features such as vitreous opacities. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The exemplary embodiments relate to mechanisms for removing undesirable features in the vitreal cavity, such as vitreous floaters. The following description is presented to enable one of ordinary skill in the art to make and use the invention and is provided in the context of a patent application and its requirements. Various modifications to the exemplary embodiments and the generic principles and features described herein will be readily apparent. The exemplary embodiments are mainly described in terms of particular methods and systems provided in particular implementations. However, the methods and systems will operate effectively in other implementations. Phrases such as “exemplary embodiment”, “one embodiment” and “another embodiment” may refer to the same or different embodiments as well as to multiple embodiments. The embodiments will be described with respect to systems and/or devices having certain components. However, the systems and/or devices may include more or less components than those shown, and variations in the arrangement and type of the components may be made without departing from the scope of the invention. Further, although specific blocks are depicted, various functions of the blocks may be separated into different blocks or combined. The exemplary embodiments will also be described in the context of particular methods having certain steps. However, the method and system operate effectively for other methods having different and/or additional steps and steps in different orders that are not inconsistent with the exemplary embodiments. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features described herein. 
     The method and system are also described in terms of singular items rather than plural items. One of ordinary skill in the art will recognize that these singular terms encompass plural. For example, an image may include one or more images. In certain embodiments, the system includes one or more processors and a memory. The one or more processors may be configured to execute instructions stored in the memory to cause and control the process set forth in the drawings and described below. As used herein, a processor may include one or more microprocessors, field-programmable gate arrays (FPGAs), controllers, or any other suitable computing devices or resources, and memory may take the form of volatile or non-volatile memory including, without limitation, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), removable media, or any other suitable memory component. Memory may store instructions for programs and algorithms that, when executed by a processor, implement the functionality described herein with respect to any such processor, memory, or component that includes processing functionality. Further, aspects of the method and system may take the form of an entirely hardware embodiment, an entirely software embodiment (including firmware, resident software, micro-code, etc.) or an embodiment combining software and hardware aspects. Furthermore, aspects of the method and system may take the form of a software component(s) executed on at least one processor and which may be embodied in one or more computer readable medium(s) having computer readable program code embodied thereon. 
     A method and system perform an ophthalmic procedure on an eye having an optical path from the lens to the retina. An image of at least part of the eye is received in a data processing unit. The image includes the optical path. The data processing unit determines keep out zone(s) and identifies undesirable feature(s) based on the image. The keep out zone(s) include the retina. The data processing unit also selects one of the undesirable feature(s) for removal. At least part of the undesirable feature is outside of the keep out zone(s). Confirmation for removal of the undesirable feature is received in the data processing unit. In response to receiving the confirmation, a control unit controls a laser to perform laser removal the at least the portion of the undesirable feature without targeting any portion of the keep out zone(s). 
       FIG.  1    is a flow chart depicting an exemplary embodiment of a method  100  for performing an ophthalmic procedure that removes undesirable features within the vitreal cavity of the eye. For simplicity, some steps may be omitted, interleaved, performed in another order and/or combined. The method  100  may include executing instructions on one or more processors. Further, the method  100  is described in the context of a non-invasive procedure. However, the method  100  may be extended to invasive procedures including but not limited to use in connection with ophthalmic surgery. The method  100  is performed by an ophthalmic laser apparatus including a data processing unit and a controller. 
     At least one image of at least a portion of the eye is received in the data processing unit, via step  102 . Receipt of the image(s) in step  102  may include receiving image data from a separate imaging system or capturing the image by a portion of the system carrying out the method  100 . Step  102  need not include rendering the image for the physician. Instead, step  102  includes obtaining data for the eye. The image(s) include the optical path of the eye. In some embodiments, the image(s) may be two-dimensional. In other embodiments, three-dimensional image(s), such as optical coherence tomograph(s) (OCTs), may be used. Thus, the image(s) may include the volume of the eye or simply a cross-section of the eye. In some embodiments, video or other mechanism for showing the progression of time may be part of the image(s) received in step  102 . 
     Keep out zones are determined by the data processing unit based on the image data, via step  104 . A keep out zone is a region of the eye in which the laser is desired not to be aimed. The keep out zones assist in ensuring that more delicate regions of the eye are not heated by the laser and, therefore, remain undamaged. Keep out zones include, for example, the retina. Step  104  may include using other patient data in addition to the image data to determine the keep out zone. For example, if the size of the patient&#39;s eye is already known, this information may be used in step  104 . Step  104  may thus include identifying structures and setting a keep out zone to be the structure and a region within a particular distance of the structure. Thus, step  104  may include identifying the location of the retina from the image and/or other data and setting the keep out zone to include the retina and the region within two millimeters of the retina. In some embodiments, the keep out zone may include the retina and the region within only one millimeter of the retina. Other distances and/or other structures may be included in other keep out zones. 
     The physician may be allowed to adjust the size and/or location of the keep out zone as part of step  104 . For example, the keep out zone corresponding to the retina that is determined by the data processing unit may include retina and the region within 0.5 millimeters of the retina. The physician may be allowed to reduced or increase the size of the keep out zone. Thus, the physician may be able to set the keep out zone for the retina as including the retina and the region within 0.25 millimeter of the retina. The physician may also be allowed to move the keep out zone to include a different part of the retina. However, there may also be a minimum distance beyond which the physician is not allowed to change the size or position of the keep out zone. In the example above, the physician may be prevented from shrinking the keep out zone such that the keep out zone is smaller than the retina. 
     The undesirable features within the vitreal cavity are identified by the data processing unit based on the image data, via step  106 . Step  106  includes identifying a set of locations corresponding to the undesirable features. In some embodiments, only those undesirable features which intersect the optical path are detected in step  106 . In other embodiments, all undesirable features that can be found based on the image data are identified. For example, vitreous floaters, or vitreous opacities, may be identified in step  106 . As used herein, a vitreous floater is synonymous with a vitreous opacity. A vitreous opacity may be any feature within the vitreous humor that has an opacity greater than a threshold and a size greater than a size threshold. Default thresholds may be provided, but may be adjusted by the user. In some embodiments, the threshold may be as low as zero. In such embodiments, any deviation from a background opacity and/or having any size may be identified as an undesirable feature. As part of step  106 , the undesirable features may also be ranked based on certain characteristics. For example, the size, location, density and/or shape of the vitreous opacity may be used to rank the vitreous opacities. These characteristics may have the same weight or different weights. In some embodiments, size is given a greater weight than location and location is given a greater weight than density. Opacities that are larger, are closer to or have a larger section within the optical path and/or are more dense/more opaque may have a higher rank. As used herein, a higher ranked vitreous opacity is a vitreous opacity is more desired to be removed. 
     One of the undesirable features is selected by the data processing unit for removal, via step  108 . At least part of this undesirable feature is outside of the keep out zone(s). Consequently, the undesirable feature may be removed by laser energy. In some embodiments, step  108  includes selecting the highest ranked (e.g. largest, most obstructive of the optical path and/or most dense). In embodiments in which the ranking is not performed as part of step  106 , the ranking may be performed as part of step  108 . Thus, the undesirable features may be set for removal in order from most desired to be removed to least important for removal. 
     A confirmation for removal of the undesirable feature is received in the data processing unit, via step  110 . In some embodiments, step  110  is optional. Step  110  may include querying the physician performing the procedure and receiving a response. For example, a “REMOVE” button may be provided on the display of a user interface (U/I). In response to the physician selecting and clicking on the REMOVE button, the confirmation is received in step  110 . If no confirmation is received, then the method may return to step  102  or the physician may be allowed to select a different undesirable feature for removal via the U/I. Confirmation of the removal is desired to aid in ensuring the safety of the patient. 
     In response to receiving the confirmation, the laser is controlled by the controller to automatically perform removal of at least part of the undesirable feature, via step  112 . For example, step  112  may include automatically aiming the laser at location(s) within the selected undesirable feature, turning the laser on for a particular time and then turning the laser off (i.e. firing the laser). The laser is aimed in step  112  such that the target for the focus of the laser energy is outside of the keep out zones. Heating from the laser may be most intense at this target. Step  112  may also include setting the laser power and/or time based on the location targeted. For example, if the region at which the laser is aimed is near a keep out zone, a lower energy or shorter application of laser energy might be used. Consequently, even if there is some heating of the keep out zone, it will be relatively small. 
     Performing the laser removal in step  112  may include further substeps. For example, if the undesirable feature is sufficiently large and/or near the keep out zone, then multiple applications of laser energy might be required for removal. Further, the undesirable feature may not only change shape, but also move as portions of the undesirable feature are vaporized. Step  112  may then include re-imaging the eye, tracking the undesirable feature and reapplying the laser energy. Tracking the undesirable feature may include comparing the image(s) of the eye taken after the laser energy is applied with those taken before the laser energy is applied and matching the identified undesirable features identified in the later image(s) with those in the previous image(s) based on size, location, shape, and/or other criteria. These processes may be performed by the data processing unit of the ophthalmic laser apparatus. The undesirable feature selected in step  108  is tracked by the ophthalmic laser apparatus so that the laser energy tends to be applied to the same undesirable feature throughout step  112 . Thus, steps  102  through  106  may be repeated as part of step  112 . This process continues until the undesirable feature is considered to be removed (untrackable or missing). Some or all of the method  100  may optionally be repeated to remove the remaining undesirable features. 
     Using the method  100 , a physician may be able to more quickly and easily remove undesirable features such as vitreous floaters, from the eye. Instead of viewing the eye, manually aiming the laser and turning the laser on or off, the physician may simply confirm removal. Because the imaging and laser removal may be performed automatically, the time taken to remove each floater may be greatly reduced. Consequently, the burden on both the physician and patient may be diminished. Because keep out zones may be automatically determined and respected by the laser removal process, the method  100  may be safer for the patient. Further, the method  100  may be performed non-invasively. Consequently, the removal of undesirable features via a laser may be improved. 
       FIG.  2    is a block diagram of an exemplary embodiment of an ophthalmic laser apparatus  200  for assisting a physician removing undesirable features from the vitreal cavity. The ophthalmic laser apparatus  200  includes an imaging system  210 , laser  212 , a controller  220 , a data processing unit  230 , a user interface (U/I)  240  and a data store  250  including any patient data, parameters and other information. For simplicity, only some components are shown. In addition, the components depicted in  FIG.  2    may be packaged together in a single apparatus. Alternatively, certain components, such as portions of imaging system, laser and data processing, may be implemented separately. Further, the components may be implemented in hardware and/or software. Also shown in  FIG.  2    is the sample eye  202  to be interrogated. The method  100  may be implemented using the system  200 . 
     The imaging system  210  may include a camera and/or other image capture device that may be managed using the controller  220 . In some embodiments, step  102  may include the controller  220  managing the focusing and capture of the image(s) by the imaging system  210 . The camera may or may not include a microscope or other magnification that allows for enhanced detail. In other embodiments, other components may be used in for the imaging system  210 . Such imaging systems  210  may or may not provide three-dimensional data for the eye. In some embodiments, video camera(s) or other mechanism for showing the progression of time may be part of the image(s) received in step  102 . Further, the resolution of the imaging system  210  is sufficiently to allow the relevant features of the eye to be determined. 
     The laser  212  is used to vaporize portions of the undesirable features. For example, the laser  212  may be a YAG laser. The U/I  240  allows output to be provided to the physician and input to be received from the physician. For example, the physician may indicate confirmation in step  110  of the undesirable feature selected for removal via the U/I  240 . The U/I  240  provides this confirmation to the data processing unit  230 . The U/I  240  may also include a display for rendering image(s) of the eye or providing other visual feedback to the physician. 
     The data processing unit  230  receives image data from the imaging system  210  in step  102 . The data processing unit  230  also performs steps  104 ,  106 ,  108  and  110 . In some embodiments, the data processing unit  230  also accesses the data store  250  in order to process the image data provided in step  102 . 
     The controller  220  communicates with the laser  212 , imaging system  2120  and data processing unit  230  and user interface  240 . The controller  220  manages the laser  212  and imaging system  210 . For example, the control  220  may focus the camera or other image capture device in the imaging system  210 , control capture of the image(s), aim the laser  212  and turn the laser  212  on/off. Using the ophthalmic laser apparatus  200 , therefore, the method  100  may be implemented. One or more of the benefits of the method  100  may thus be achieved. 
       FIG.  3    is a flow chart depicting an exemplary embodiment of a method  150  for performing an ophthalmic procedure that removes undesirable features. For simplicity, the method  150  is described in the context of removal of vitreous opacities, or floaters. Some steps may be omitted, interleaved, performed in another order and/or combined. The method  150  may include executing instructions on one or more processors. Further, the method  150  is described as being performed by the system  200 . However, the method  150  may be performed by other apparatuses (not shown). The method  150  may be performed non-invasively. In other embodiments, the method  150  may be incorporated in to an ophthalmic surgical procedure. 
       FIGS.  4 A- 4 L  depict exemplary embodiments of images/image data  300  of the eye during the method  150 .  FIGS.  4 A- 4 L  are not to scale. The images  300  may or may not be rendered and shown to the physician via the U/I  240 . A particular patient, condition or response is not intended to be shown in  FIGS.  4 A- 4 L . In addition, the images actually captured using the method  150  may not correspond to the orientation shown. For example, images captured by a camera pointed into the pupil  308  may capture a view orthogonal to that shown in  FIGS.  4 A- 4 L . Images captured by an OCT indicate the volume of the eye. Thus, such OCT images include but are not limited to the views shown in  FIGS.  4 A- 4 L .  FIGS.  4 A- 4 L  are, therefore, for explanatory purposes only and not intended to represent a specific image. 
     Image(s) of at least a portion of the eye are captured, via step  152 . Step  152  may include the controller  220  managing the imaging system  210  to capture the image. As part of step  152 , the image data for the image(s) are received by the data processing unit  230 . Thus, at least part of step  152  is analogous to step  102 . The image capture and image data may be for two dimensional or three dimensional views of the eye.  FIG.  4 A  depicts an image  300  of the eye that could be considered captured in step  152 . The cornea  302 , lens  304 , iris  306 , pupil  308 , vitreal cavity  310  and retina  320  are indicated for the purposes of explanation. Also shown are vitreous opacities  330 ,  332  and  334 . Although the entire eye is shown in  FIG.  4 A , in other embodiments, the images capture data for only a portion of the eye. For example, only the optical path and surrounding region might be imaged. 
     Keep out zones are determined by the ophthalmic laser apparatus based on the image data and any additional data for the patient, via step  154 . Step  154  is analogous to step  104 . Step  154  may thus include identifying structures such as the retina  320  and setting a keep out zone to be the structure and a region within a particular distance of the structure. The physician may be allowed to adjust the size and/or location of the keep out zone  322  as part of step  154 . For example, the keep out zone  322  might be made thinner such that a region a smaller distance from the retina  320  is included. However, there may also be a minimum distance beyond which the physician is not allowed to change the size or position of the keep out zone. For example, the keep out zone may be required to include the portion of the retina  320  already within the keep out zone and a region within some small distance of this portion of the retina  320 .  FIG.  4 B  depicts the information added in step  154 . Thus, the optical path  312  is indicated by dotted lines. In addition, a keep out zone  322  indicated by dashed lines has also been determined. The keep out zone  322  includes a portion of the retina  320  in and around the optical path  312  and a region a particular distance anterior of the retina  320 . Other keep out zones (not shown in  FIG.  4 B  for simplicity) may be provided in step  154 . 
     The vitreous opacities are identified by the data processing unit  230  based on the image data, via step  156 . Step  156  may also utilize information in the data store  250 . Step  156  is thus analogous to step  106 . Thus, the vitreous opacities  330 ,  332  and  334  are defined in step  156 . In some embodiments, the vitreous opacity  334  might be omitted from the vitreous opacities determined in step  156  because the vitreous opacity may be sufficiently small and/or sufficiently far from the optical path  312  to be considered by the method  150 . However, in other embodiments, the vitreous opacity  334  is included. Step  156  may also include ranking the vitreous opacities  330 ,  332  and  334  based on size, location and density. The ranking is presumed to be, in order,  332 ,  334  and  336 . 
     One of the vitreous opacities  330 ,  332 ,  334  is selected by the data processing unit  230  for removal, via step  158 . Step  158  is analogous to step  108 . In the embodiment shown, the vitreous opacity  330  is selected for removal because it was ranked first in step  156 . In embodiments in which the ranking is not performed as part of step  156 , the ranking may be performed as part of step  158 . 
     A confirmation for removal of the undesirable feature is received by the data processing unit  230 , via step  160 . Step  160  is analogous to step  110  optional. Step  140  may include receiving input from a physician via the U/I  240 . response. If no confirmation is received, then the method may return to step  152  or the physician may be allowed to select a different undesirable feature for removal via the U/I. 
     In response to receiving the confirmation, the laser  212  is controlled by the controller  210  to automatically performed removal of at least part of the vitreous opacity  330 . In order to do so, steps  162 ,  163 ,  164 ,  166 ,  168  and  170  may be used. For example, the controller  220  automatically aims the laser  210  at location(s) within the selected vitreous opacity  330  and outside of the keep out ozone  222 , via step  162 . If a sufficient amount of the vitreous opacity  330  selected for removal were in the keep out zone  322 , then the physician may be allowed to override the method  150  and focus the laser  210  within the keep out zone  322 , via step  163 .  FIG.  4 C  depicts the image  300  with the laser aimed at target  350 . This target  350  is within the selected vitreous opacity  330  and outside of the keep out zone  322 . Further, the target  350  is within the optical path  312 , which may be desirable. As a result, the portion of the vitreous opacity  330  within the optical path  312  and more likely to affect vision may be removed first. 
     Once aimed, the laser  210  may be fired using the controller  220  to turn the laser  210  on and off, via step  164 . As a result, at least a portion of the selected vitreous opacity  330  is vaporized. 
     The eye is optionally reimaged, via step  166 . Step  166  is analogous to step  152 .  FIG.  4 D  depicts the image  300  of the eye after step  166  is performed. Thus, the vitreous opacity  330 ′ is smaller, has changed shape and may have moved. It is determined whether the remaining portion of the selected vitreous opacity  330 ′ may be tracked. Tracking may include comparing the image(s) of the eye taken after the laser energy is applied in step  164  with those taken in step  152  and matching the size, location, shape and/or other features of the vitreous opacities. As can be seen in  FIGS.  4 B and  4 D , the vitreous opacity  330 ′ corresponds to the vitreous opacity  330  and is still sufficiently large for tracking. The selected vitreous opacity  330 ′ is thus tracked in step  170 . Stated differently, the shape and location of the vitreous opacity  330 ′ may be saved. Step  162  may then be returned to. Steps  162 ,  164 ,  166 ,  168  and  170  may be iteratively performed until the vitreous opacity  330 ′ may no longer be tracked. 
     Thus,  FIG.  4 E  depicts the target  350 ′ for the vitreous opacity  330 ′ determined on the next (second) iteration of step  162 .  FIG.  4 F  depicts the target  350 ″ on the third iteration of the method  150 . Thus, the vitreous opacity  330 ″ is even smaller. The target  350 ″ is both at least partially within the vitreous opacity  330 ″ and outside of the keep away zone  322 .  FIG.  4 G  depicts the image after the vitreous opacity  330 ′″ after the third iteration of the fining of the laser in step  164 . The vitreous opacity  330 ′″ can no longer be tracked. Thus, the vitreous opacity  330 ′″ may be considered removed. 
     Because it is determined in step  168  after three iterations that the vitreous opacity  330 ′″ can no longer be tracked, it is determined in step  172  whether there may be additional vitreous opacities to be removed. As can be seen in  FIG.  4 G , vitreous opacities  332  and  334  remain. Thus, step  154  is returned to using the image data from step  166 . Alternatively, step  152  may be returned to in order to obtain more image data. 
     Thus, steps  154  through  172  may be repeated. As can be seen in  FIG.  4 G , the next vitreous opacity  332  is targeted in step  162 . The target  360  for the vitreous opacity  443  is both within the vitreous opacity  332  and outside of the keep out zone  322 .  FIG.  4 H  depicts the image after step  164  is performed for the vitreous opacity  332 . Thus, only a portion of the vitreous opacity  332 ′ remains. However, substantially all of the vitreous opacity  332 ′ is in the keep out zone  322 . In some embodiments, this would complete removal of the vitreous opacity  332 ′. However,  FIG.  4 I  depicts a target  360 ′ on the vitreous opacity  332 ′ and within the keep out zone  320 . This is because the physician has used step  163  to override the requirement that the laser  210  be focused outside of the keep out zone  322 . The laser  210  is fired by the controller  220  in step  164 .  FIG.  4 J  depicts an image of the eye taken in step  166 . Thus, the vitreous opacity  332 ′ has been completely removed. 
     In some embodiments, this might complete the method  150  because vitreous opacities within the optical path  312  have been removed. However, in this case, removal of the remaining identified and trackable vitreous opacity  334  is desired. Thus, the method  150  repeats and the physician confirms removal of vitreous opacity  334  in the next iteration of step  160 .  FIG.  4 K  depicts the image  300  after the controller aims the laser in step  152 . Thus, target  370  is shown. The target  370  for the laser  210  is within the vitreous opacity  334  and outside of the keep out zone  322 . The laser  210  may then be fired in step  164 . The steps  162 ,  163 ,  164 ,  166 ,  168  and  170  may be repeated until the vitreous opacity  334  is not trackable and removed. 
       FIG.  4 L  depicts an image of the eye after removal of the vitreous opacity  334 . The image  300  may be captured after the last iteration of step  166  for the vitreous opacity  334 . Thus, step  168  determines that the opacity (not present in  FIG.  4 L ) is not trackable. Step  172  may also determine that there are not more vitreous opacities. This is because the opacity  330 ″ may be sufficiently small that it does not meet any of the thresholds set for localizing opacities. Thus, the method  150  completes. 
     Using the method  150 , a physician may be able to more quickly and easily remove vitreous floaters, from the eye. Instead of viewing the eye, manually aiming the laser and turning the laser on or off, the physician may simply confirm removal in step  160  and optionally change or override keep out zones in steps  154  and/or  163 . The system  200  may perform some or all of the method  150 . Thus, the burden on the physician may be reduced and the time taken to remove each floater may be greatly reduced. Consequently, the burden on both the physician and patient may be diminished. The method  150  may be safer for the patient. Further, the method  150  may be performed non-invasively. Consequently, the removal of undesirable features via a laser may be improved. 
     A method and system for assisting a physician in non-invasively removing undesirable features in an eye have been described. The method and systems have been described in accordance with the exemplary embodiments shown, and one of ordinary skill in the art will readily recognize that there could be variations to the embodiments, and any variations would be within the spirit and scope of the method and system. Accordingly, many modifications may be made by one of ordinary skill in the art without departing from the spirit and scope of the appended claims.