COMPUTERIZED TREATMENT PLAN WITH ALTERNATIVES FOR GUIDING OPHTHALMIC SURGERY

Particular embodiments disclosed herein provide an apparatus and corresponding methods for guiding ophthalmic surgery and enabling a surgeon to switch, after initiating surgery, between a primary treatment plan and one or more backup plans. Switching between a first plan and a second plan may be performed while omitting presentation of steps of the second plan compatible with implemented steps of the first plan. A treatment plan may include guides imposed on a live video of an eye of the patient that has been registered with respect to a pre-operative image. When switching between plans, initiating registration with respect to the pre-operative image is omitted. A treatment plan may define steps for placement of an IOL such as incision, rhexis, LRI, crystalline lens removal, placement of an IOL, alignment of a toric IOL, and post-operative data collection. Upon switching between first and second, previously implemented compatible steps are omitted from presentation of the second plan.

TECHNICAL FIELD

The present disclosure relates generally to methods for computerized guidance during performance of ophthalmic surgery, such as the placement of intraocular lenses (IOL) for the treatment of cataracts and other conditions.

BACKGROUND

Light received by the human eye, passes through the transparent cornea covering the iris and pupil of the eye. The light is transmitted through the pupil and is focused by a crystalline lens positioned behind the pupil in a structure called the capsular bag. The light is focused by the lens onto the retina, which includes rods and cones capable of generating nerve impulses in response to the light.

Through age or disease, the crystalline lens may become cloudy, a condition known as a cataract. Cataracts, and other conditions, are readily treated by removing the crystalline lens and inserting an artificial lens, known as an intraocular lens (IOL). The IOL may be fabricated to additionally correct for aberrations of the patient's eye, such as astigmatism. Inasmuch as astigmatism is the result of asymmetry of the eye, the IOL must be aligned with the asymmetry of the eye in order to compensate for it. The IOL is therefore provided with markers, such as rows of dots at the perimeter of the IOL, which define an axis that may be used to align the IOL. The IOL may be implemented as a toric IOL, which includes spring-like arms, known as haptics, that hold the IOL in place within the capsular bag.

Ophthalmic surgery, such as the placement of an IOL, requires thorough treatment planning beforehand. The treatment plan may be presented to the surgeon during surgery as a printout or as digital image guidance. For example, the treatment plan may include guides superimposed on an image of the patient's eye captured using a digital microscope.

BRIEF SUMMARY

The present disclosure relates generally to a system creating and presenting a primary treatment plan and one or more backup plans for ophthalmic surgery.

Particular embodiments disclosed herein provide a method and corresponding apparatus for guiding ophthalmic surgery. The method includes loading, by a computing device, two or more ophthalmic surgical treatment plans (“treatment plans”) having a common pre-operative image of a patient, the two or more treatment plans being different from one another. A live video of an eye of the patient is received and registration of the live video with respect to the pre-operative image is initiated. The method further includes initiating, by the computing device, on a display device coupled to the computing device, presentation of one or more first steps of a first treatment plan of the two or more treatment plans, the one or more first steps defining superimposition of one or more first guides on the live video. The method includes receiving, by the computing device, an instruction to switch to a second plan of the two or more treatment plans. In response to the instruction, the method includes initiating, by the computing device, on the display device, presentation of one or more second steps of a second plan of the two or more treatment plans, the one or more second steps defining superimposition of one or more second guides on the live video, the one or more second guides being different from the one or more first guides.

DETAILED DESCRIPTION

In prior approaches to performing ophthalmic surgery, a single treatment plan is created and loaded into a computing device, such as a digital microscope. If a change in treatment plan is needed, either (a) the surgeon must simply implement the change without the guidance of a treatment plan or (b) the surgery must be paused to load a new treatment plan into the computing device. Where a new treatment plan is loaded, initial steps of the new plan will need to be repeated, such as registering live images of the patient's eye with a pre-operative image of the new plan.

Particular embodiments of the present disclosure provide a primary treatment plan and one or more backup plans that are loaded into a computing device prior to a surgical procedure. If a foreseeable event corresponding to one of the one or more backup plans occurs during the surgical procedure, the backup plan may be selected and presented without the need to reload a new treatment plan onto the computing device.

FIG.1illustrates an interface100for creating a primary treatment plan and one or more backup plans for performing ophthalmic surgery. The examples presented below describe surgical procedures including replacing the crystalline lens of a patient with an IOL. As an example, a primary treatment plan may include a treatment plan for placing and aligning a toric IOL and backup plans may address contingencies such as bag rupture, patient decision to switch to a different IOL, or other contingencies. The implementations described herein may also be applied to other types of ophthalmic surgery.

The interface100may present patient information to assist a user in creating the primary treatment plan and the one or more backup plans. The patient information may include a pre-operative image102. The pre-operative image102may be an image of the patient's eye captured using an imaging device, such as a pre-operative imaging device, examples of which include an optical coherence tomography (OCT), a rotating camera (e.g., a Scheimpflug camera), a magnetic resonance imaging (Mill) device, a keratometer, an ophthalmometer, an optical biometer, or any other digital imaging device. The pre-operative image102may be captured prior to creating the primary treatment plan and the one or more backup plans. The patient information may include patient identification data104, such as patient's name, demographic attributes, photograph, or other identification data. The patient information may include eye measurement data106. The eye measurement data106may include keratometry, biometry, refraction measurement (spherical aberration, cylindrical aberration, astigmatism), and measurements of anatomy of the eye (e.g., limbus diameter). The eye measurement data106may include data describing incisions to be made, such as a radius and angle for each of a primary incision and one or more secondary incisions. The eye measurement data106may include data describing limbal release incisions (LRI), such as in the form of a diameter and angular extent of each LRI.

The interface100may include a pallet108enabling the selection of guides to be placed with respect to the pre-operative image102. The pallet108may be embodied as, e.g., a grouping of selectable icons, a menu, a picklist, or any other user interface element known in the art. The pallet108may include an incision element110, rhexis element112, LRI element114, centration element116, IOL axis element118, and possibly one or more other elements120. A user may interact with each of the above-described elements by means of clicking with a pointing device (mouse, trackpad), tapping on a touch sensitive element (touch screen, trackpad), making a predefined gesture on the touch sensitive element, inputting a keystroke, voice command, pressing a foot pedal, or any input means known in the art.

Referring toFIG.2A, while still referring toFIG.1, the incision element110, when selected by a user, may enable a user to select a location on the pre-operative image102for placing an incision guide200. For example, the pre-operative image102may include representations of the cornea202, limbus204, and sclera206of the patient's eye. The user may therefore place incision guide200at a location in the cornea near the limbus. The user may place multiple incision guides200, such as a primary incision guide200and one or more secondary incision guides200.

Referring toFIG.2B, while still referring toFIG.1, the rhexis element112, when selected by a user, may enable a user to select a location on the pre-operative image102for placing a center208of a rhexis and placing a perimeter210of the rhexis, e.g., a circle centered on the center208and having a diameter specified by the user. The rhexis is an opening in the capsular bag that is formed to enable removal of the crystalline lens and placement of an IOL.

Referring toFIG.2C, while still referring toFIG.1, the LRI element114, when selected by a user, may enable a user to select a location on the pre-operative image for placing one or more LRI guides212. The LRI guides212define placement of limbal release incisions (LRI) and may be placed along the limbus204of the eye. The interface100may automatically identify the limbus204, such as using machine learning or other automated image processing approach. Accordingly, the interface100may receive an angular position and extent of the LRI on the limbus204from a user upon selection of the LRI element114.

Referring toFIG.2D, while still referring toFIG.1, the centration element116, when selected by a user, may enable a user to select a location on the pre-operative image for placing a center214of a centration guide and one or more rings216centered on the center214. For example, the rings216may define a desired position of the perimeter of an IOL. A pair of rings216may be placed with the gap between the rings216corresponding to the desired position of the perimeter of the IOL.

Referring toFIG.2E, while still referring toFIG.1, the IOL axis element118, when selected by a user, may enable a user to select a location on the pre-operative image for placing an IOL axis218. The IOL axis218may be a line passing through the center214defined for the centration guide or may use a separately defined center. The IOL axis218defines a desired alignment of a toric IOL having asymmetric properties for the treatment of astigmatism. The IOL axis218represents a desired alignment of marking dots on the toric IOL. The interface may further automatically place protractors220indicating angular measurements to either side of the IOL axis218or place and size the protractors220in response to inputs from the user following selection of the IOL axis element118.

FIG.3illustrates a method300that may be executed by a computing device using inputs received through the interface100or other interface in order to create a primary treatment plan and one or more backup plans. The method300may include creating, at step302, a new plan. This may include creating a primary treatment plan in the form of a data object, file, or other data structure to store data defining the primary treatment plan. The primary treatment plan may be part of a plan hierarchy to which one or more backup plans may also be added. The plan hierarchy created at step302may be populated using the interface100or other interface in subsequent steps of the method300as described below, including populating the primary treatment plan and one or more backup plans.

The method300may include receiving, at step304, a pre-operative image102and receiving, at step306, patient data, such as patient identification data104and eye measurement data106as described above. The pre-operative image102may be added to the plan hierarchy and be used for the primary treatment plan and one or more backup plans of the plan hierarchy. As an alternative, a backup plan of the one or more backup plans may use a different pre-operative image102.

The subsequent steps of the method300are described below with respect to a “current plan,” which may be understood as whichever of the primary treatment plan and one or more backup plans is currently being modified by a user according to the subsequent steps of the method300. For example, following step302, the current plan may be the primary treatment plan by default.

The method300may include receiving, at step308, inputs from the user that one or both of (a) configure a guide for a step of the current plan and (b) add text, measurement data, or other information defining the step of the current treatment plan. As an example, for implantation of a toric IOL, a step of the current treatment plan may include any of incision (which may include creating LRI), rhexis formation, removal of the crystalline lens, implantation, centration, alignment, and post-operative data collection. Configuring a guide may include configuring a guide according to the approaches described above with respect toFIGS.2A to2E. The method300may include adding, at step310, the guides and/or treatment plan from step308to the step of the current treatment plan.

The interface100may receive inputs from the user instructing a switch of the current treatment plan, such as from the primary treatment plan to a backup plan, from a backup plan to the primary treatment plan, or from a first backup plan to a second backup plan. Whichever plan is the new current plan following the switch may then have one more steps and guides added thereto (see steps308and310, above) in response to inputs received through the interface100.

If a switch is found, at step312, to be instructed by the user and if the instruction is found, at step316, to be an instruction to create a new backup plan, a new backup plan is created at step318. The backup plan and the primary treatment plan may be part of a common data structure representing the same surgical procedure, the common data structure is referred to herein as the plan hierarchy. Following creation at step318, the backup plan may then have one or more steps and one or more guides added thereto (see steps308and310).

The method300may include evaluating, at step320, whether the new backup plan is compatible with a parent plan, i.e., the primary treatment plan or previously created backup plan. In some instances, one or more steps or guides of the parent plan may be either identical to or compatible with corresponding one or more steps or guides of the new plan. “Compatible” as used herein therefore indicates that in the event of a switch between the first plan and the second plan, the one or more steps need not be repeated and/or the same one or more guides may be used. Whether the new plan created at step318is compatible with the current plan or other previously-created plan may be determined in response to an input from the user indicating compatibility. For example, the user may provide inputs indicating which steps and/or guides of the parent plan are compatible with the new plan.

If the new plan is determined at step320to be compatible, then, at step322, the method300may include importing one or more previously defined steps of the parent plan into the new plan so that the user does not have to repeat entry of these steps into the new plan and may simply proceed with entry of subsequent steps to the new plan at subsequent iterations of step310. Alternatively step322may include adding the new plan as a branch with respect to the parent plan. A “branch” may be an indication of compatibility between the parent plan and the new plan indicating that a step of the parent plan is compatible with a corresponding step of the new plan and the corresponding step of the new plan would not need to be performed in the event of a switch. As an example, a branch may indicate that an incision step of the parent plan is compatible with the incision step of the new plan such that upon switching from the parent plan to the new plan during a surgery, the incision step of the new plan may be omitted.

The method300may include switching, at step324, the current plan to the plan indicated in the instruction from step312, i.e., the new plan created at step318or an existing plan referenced by the instruction from step312. The method300may then continue with addition of a new step to the current plan at step310. Accordingly, the user may add steps to the newly created plan from step318or the existing plan.

The method300may continue until the user provides, at step314, an input indicating that creation of the plan hierarchy is finished.

FIG.4illustrates an example plan hierarchy400that may be created according to the method300or other method. The plan hierarchy400may include a plan400a(e.g., the primary treatment plan) and one or more other plans400b,400c(e.g., backup plans). The plans400a,400b,400cmay have common data such as patient data402received at step306and a registration step404with respect to a common pre-operative image102received at step304.

The registration step404may be performed by capturing a live image (e.g., intra-operative image) of the patient's eye and matching ocular anatomy, such as the unique patterns of blood vessels on the sclera and/or retina and/or the unique patterns of the limbus and/or iris represented in the image, to representations of corresponding ocular anatomy in the pre-operative image102to determine the orientation of the eye. The registration step404may include determining a transformation relating the orientation of the eye in the live image to the orientation of the eye in the pre-operative image102. The locations, orientations, and/or size of guides defined in the treatment plans400a,400b,400cmay then be transformed according to the transformation and superimposed on the live image. The live image may be a frame of a plurality of frames of a video feed from an imaging device used during surgery. Accordingly, the registration step404may include initiating registration with respect to frames of the video feed, which may then be repeated throughout the surgery for every frame of the video feed or periodically, e.g., every N frames, where N is greater than 1, or in response to detection of movement of the patient's eye.

Each plan400a,400b,400cmay include other steps such as an incision step406a,406b,406c, removal step408a,408b,408c, implantation step410a,410b,410c, centration step412a,412b,412c, and a post-operative data collection step416a,416b,416c. Some steps of a plan may not be present in other plans. For example, plan400amay correspond to implantation of a toric IOL and therefore includes an alignment step414athat is not present in other plans400b,400c.

The plan hierarchy400may include compatibility indicated by branches418. For example, plan400amay correspond to placement of a toric IOL whereas plan400bcorresponds to a backup plan in the case of rupture of the capsular bag such that a non-toric IOL must be used and sulcus placement is required. The plans400a,400bmay be compatible with respect to the incision steps406a,406band removal steps408a,408b. This is not to say that the incision steps406a,406bare identical. It may be that one or more incision guides200of plan400aare different from the one or more incision guides200of plan400b. However, in the event that a switch is made to plan400b, the incisions from plan400amay be used. In some cases, the incision steps may be compatible but not completely overlapping. For example, the incision step406amay not include LRI whereas incision step406bmay require additional LRI for sulcus placement of a monofocal IOL. Accordingly, in the event of a switch from plan400ato plan400b, guides for placing the LRI may be displayed even when the incision step406awas completed prior to the switch.

In another example scenario, plan400ccorresponds to a different type of IOL than plan400a. In the event that a patient decides to switch from a toric IOL to a non-toric IOL, the surgeon may switch to plan400c, for example, without delaying the surgery to create a new treatment plan. Where the incision steps406a,406care compatible, such a switch could even be made during the surgery.

The plan hierarchy400illustrates a further benefit of the implementations described herein. The post-operative data that is collected for a surgery should correspond to the actual surgery performed. Upon switching between plans400a,400b,400c, the post-operative data collection step416a,416b,416cof whichever plan is the selected plan upon completion of the surgery may be performed. The post-operative data collection may include automatic collection of data from video data captured during the surgery and/or prompts for the surgeon to enter post-operative data. In this manner, post-operative care may be performed according to the plan actually implemented even when a change between plans400a,400b,400coccurred during the surgery. In some implementations, the post-operative data collection step of plans that were started but not completed is omitted. For example, the post-operative data collection step416amay be omitted when switching from plan400ato plan400bduring the surgery.

FIG.5illustrates an example interface500for presenting plans400a,400b,400cto a surgeon during a surgery. The interface500may include selected plan data502. The selected plan data502may include data common to all the plans400a,400b,400c, such as the patient data402. The selected plan data502may include specific data corresponding to whichever of the plans400a,400b,400cis a plan most recently selected by the surgeon for implementation. For example, for the plan400acorresponding to placement of a toric IOL, the selected plan data502may include data defining a desired alignment of the toric IOL, a specification (e.g., refractive properties) of the toric IOL, or other data. For the plan400bcorresponding to bag rupture, the selected plan data502may include specifications of the non-toric IOL and describing sulcus placement thereof.

The interface500may include a live image510of the patient's eye captured during the surgery. For example, the live image510may include successively displayed frames of a video feed from a digital microscope having the patient's eye in the field of view thereof. The live image510may be registered as described above and have guides superimposed thereon according to whichever of the treatment plans400a,400b,400cis the selected plan. For example, the IOL axis218and corresponding protractors220may be displayed for plan400acorresponding to placement of a toric IOL.

In the case of a switch between plans400a,400b,400c, some guides may correspond to a plan other than the selected plan. For example, suppose plans400a,400bhave different incision guides200but a switch from plan400ato plan400boccurred after performing the incision step406a. In that case, the incision guides200presented throughout implementation of the plan400bmay be those of the plan400a.

In some scenarios, a switch between a first plan and a second plan of the plans400a,400b,400cmay include an automatic or predefined modification of one or more steps of the second plan. For example, an incision for a first plan may affect the post-operative astigmatism of the patient's eye. Accordingly, if the second plan includes placement of a toric IOL correcting for astigmatism, the refractive power and orientation of the toric IOL defined by the second plan may be recalculated to account for the incision step of the first plan. This calculation may be specified in the plan hierarchy400or may be automatically calculated in response to a post-incision switch from the first plan to the second plan.

The interface500may include plan elements504a,504b,504ceach corresponding to one of the plans400a,400b,400cof the plan hierarchy400. Each plan element504a,504b,504cmay have a label indicating the scenario to which the plan element504a,504b,504ccorresponds, such as “Toric IOL,” “Bag Rupture,” “Non-Toric IOL,” or other label. Upon selection of a plan element504a,504b,504c, the interface500may change the guides superimposed on the live image510and the selected plan data502of the plan400a,400b,400ccorresponding to the selected plan element504a,504b,504c. For a switch from a first plan to a second plan of the plans400a,400b,400c, the guides and plan data502may correspond to the first incompatible step of the second plan. For example, where the registration step404, incision steps406a,406b, and removal steps408a,408bare compatible between plan400a,400b, the guides and plan data502displayed upon a switch from plan400ato plan400bfollowing the removal step408amay correspond to the implantation step410b.

FIG.6illustrates an example method600that may be performed by a computing device using inputs received through the interface500or other interface. The method600may include loading, at step602, a plan hierarchy400including a plurality of plans400a,400b,400cincluding a primary treatment plan and at least one backup plan. The method600may include receiving, at step604, selection of a plan (“the selected plan”) from the plan hierarchy. For example, the surgeon may select the primary treatment plan400ausing plan element504a. In response, the method600includes presenting, at step606, the first un-implemented step of the selected plan. Step606may include presenting guides and other data defined for the last un-implemented step of the selected plan. In the example ofFIG.4, presenting guides would include the registration step404. A step of a treatment plan400a,400b,400cmay be deemed implemented either (a) as soon as the step is presented in the interface500, (b) as soon as the surgeon advances from the step to the next step in the selected treatment plan or switches to a different treatment plan, or (c) in response to an input from the surgeon indicating that step has been implemented.

The method600may include determining, at step608, whether the surgeon has switched plans. For example, the surgeon may commence performing plan400aand then switch to plan400bby selecting plan element504b. If so, the method600may include setting the new plan selected by the surgeon as the selected plan and then identifying, at step610, a first step of the selected plan that is either (a) non-repetitive with respect to implemented steps of the previous selected plan and (b) incompatible with respect to implemented steps of the previous selected plan. The step of the selected plan identified at step610may then be presented at step606.

As used herein “non-repetitive” may be understood as not corresponding to a previously implemented identical or compatible step. For example, compatible incision steps406a,406bcorrespond to one another and can be repetitive with respect to one another. Suppose the registration step404of plan400awas implemented prior to switching to plan400b. In that case, performing the registration step404is repetitive and is not repeated. Instead, the incision step406bwould be performed as the first non-repetitive or incompatible step since the corresponding incision step406ahas not been performed and therefore step406bis not repetitive. Suppose that the incision step406aand removal step408ahave been performed prior to switching from plan400ato plan400b, the first non-repetitive or incompatible step of plan400bwould therefore be the implantation step410b. Likewise, if any of the implantation step410a, centration step412a, and alignment steps414ahave been performed for the plan400aprior to switching to plan400bdue to capsular bag rupture, the first non-repetitive or incompatible step of plan400bwould be implantation step410bof a non-toric IOL.

In the absence of a switching between plans, following presentation of a step for the selected plan at step606, the interface500may be advanced, at step612, to the next step of the selected plan. Advancing may be performed in response to an input from the surgeon instructing the interface500to advance to the next step.

The method600may continue until the last step of the selected plan, e.g., a post-operative-data collection step416a,416b,416bfor the selected plain is implemented.

FIG.7illustrates an example computing system700that implements, at least partly, one or more functionalities described herein in response to inputs to the interface100and/or interface500. The computing system700may also implement the methods300and/or600. The computing system700may be integrated with an imaging device, such as a digital microscope, or be a separate computing device receiving images of a patient's eye from the imaging device. In practice, the computing device700used to implement the method300and present the interface100may be different from the computing device700used to implement the method600and present the interface500. For example, the computing device700used to implement the method300and present the interface100may be a general purpose computing device whereas the computing device700used to implement the method600and present the interface500may be part of a surgical imaging system.

As shown, computing system700includes a central processing unit (CPU)702, one or more I/O device interfaces704, which may allow for the connection of various I/O devices714(e.g., keyboards, displays, mouse devices, pen input, etc.) to computing system700, network interface706through which computing system700is connected to network790(which may be a local network, an intranet, the internet, or any other group of computing systems communicatively connected to each other, as described in relation toFIG.1), a memory708, storage710, and an interconnect712.

In cases where computing system700is an imaging system, such as a digital microscope, computing system700may further include one or more optical components for obtaining ophthalmic imaging of a patient's eye as well as any other components known to one of ordinary skill in the art. In cases where computing system700is a surgical microscope, computing system700may further include many other components known to one of ordinary skill in the art to perform the ophthalmic surgeries described herein as known to one of ordinary skill in the art.

CPU702may retrieve and execute programming instructions stored in the memory708. Similarly, CPU702may retrieve and store application data residing in the memory708. The interconnect712transmits programming instructions and application data, among CPU702, I/O device interface704, network interface706, memory708, and storage710. CPU702is included to be representative of a single CPU, multiple CPUs, a single CPU having multiple processing cores, and the like.

Memory708is representative of a volatile memory, such as a random access memory, and/or a nonvolatile memory, such as nonvolatile random access memory, phase change random access memory, or the like. As shown, memory708may store a plan creation module716including executable code instructing the CPU702to implement one or both of the interface100and the method300. The memory708may store a plan presentation module718including executable code instructing the CPU702to implement one or both of the interface500and the method600.

Storage710may be non-volatile memory, such as a disk drive, solid state drive, or a collection of storage devices distributed across multiple storage systems. Storage710may optionally store a plan hierarchy400as described herein.

Additional Considerations

The preceding description is provided to enable any person skilled in the art to practice the various embodiments described herein. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments. For example, changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. Also, features described with respect to some examples may be combined in some other examples. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method that is practiced using other structure, functionality, or structure and functionality in addition to, or other than, the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.