WO2024127205A1

WO2024127205A1 - Robotic surgical procedure with rapid tool exchange

Info

Publication number: WO2024127205A1
Application number: PCT/IB2023/062467
Authority: WO
Inventors: Zev Sohn; Daniel Glozman
Original assignee: Forsight Robotics Ltd.
Priority date: 2022-12-11
Filing date: 2023-12-11
Publication date: 2024-06-20

Abstract

Apparatus and methods are described for performing robotic microsurgery on a portion of a body of a patient. A robotic system (20) includes an end effector (34) that has a tool mount (44). Each of a plurality of tools (21), which having different functions from each other, defines a mount-engagement portion (40) that includes a pair of levered arms (48) that are hingedly coupled to each other. The tools (21) are reversibly coupled to the tool mount (44) by the levered arms (48) being pivoted with respect to each other such as to close around the tool mount (44). Other applications are also described.

Description

ROBOTIC SURGICAL PROCEDURE WITH RAPID TOOL EXCHANGE

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application claims priority from U.S. Provisional Patent Application No. 63/431 ,710 to Sohn, filed December 11 , 2022, entitled "Robotic Surgical Procedure With Rapid Tool Exchange," which is incorporated herein by reference.

FIELD OF EMBODIMENTS OF THE INVENTION

Some applications of the present invention generally relate to medical apparatus and methods. Specifically, some applications of the present invention relate to apparatus and methods for performing microsurgical procedures in a robotic manner.

BACKGROUND

Cataract surgery involves the removal of the natural lens of the eye that has developed an opacification (known as a cataract), and its replacement with an intraocular lens. Such surgery typically involves a number of standard steps, which are performed sequentially.

In an initial step, the patient's face around the eye is disinfected (typically, with iodine solution), and their face is covered by a sterile drape, such that only the eye is exposed. When the disinfection and draping has been completed, the eye is anesthetized, typically using a local anesthetic, which is administered in the form of liquid eye drops. The eyeball is then exposed, using an eyelid speculum that holds the upper and lower eyelids open. One or more incisions (and typically two or three incisions) are made in the cornea of the eye. The incision(s) are typically made using a specialized blade, which is called a keratome blade. At this stage, lidocaine is typically injected into the anterior chamber of the eye, in order to further anesthetize the eye. Following this step, a viscoelastic injection is applied via the corneal incision(s). The viscoelastic injection is performed in order to stabilize the anterior chamber and to help maintain eye pressure during the remainder of the procedure, and also in order to distance the anterior lens capsule from the cornea.

In a subsequent stage, known as capsulorhexis, a part of the anterior lens capsule is removed. Various enhanced techniques have been developed for performing capsulorhexis, such as laser-assisted capsulorhexis, zepto-rhexis (which utilizes precision nano-pulse technology), and marker-assisted capsulorhexis (in which the cornea is marked using a predefined marker, in order to indicate the desired size for the capsule opening). Subsequently, it is common for a fluid wave to be injected via the corneal incision, in order to dissect the cataract's outer cortical layer, in a step known as hydrodissection. In a subsequent step, known as hydrodelineation, the outer softer epi-nucleus of the lens is separated from the inner firmer endo-nucleus by the injection of a fluid wave. In the next step, ultrasonic emulsification of the lens is performed, in a process known as phacoemulsification. The nucleus of the lens is broken initially using a chopper, following which the outer fragments of the lens are broken and removed, typically using an ultrasonic phacoemulsification probe. Further typically, a separate tool is used to perform suction during the phacoemulsification. When the phacoemulsification is complete, the remaining lens cortex (i.e., the outer layer of the lens) material is aspirated from the capsule. During the phacoemulsification and the aspiration, aspirated fluids are typically replaced with irrigation of a balanced salt solution, in order to maintain fluid pressure in the anterior chamber. In some cases, if deemed to be necessary, then the capsule is polished. Subsequently, the intraocular lens (IOL) is inserted into the capsule. The IOL is typically foldable and is inserted in a folded configuration, before unfolding inside the capsule. At this stage, the viscoelastic is removed, typically using the suction device that was previously used to aspirate fluids from the capsule. If necessary, the incision(s) is sealed by injecting balanced salt solution into the corneal stroma until diffuse whitening occurs, thereby causing the internal tissue to be pressed against the external tissue of the incision, such as to force closed the incision.

SUMMARY

In accordance with some applications of the present invention, a mount-engagement portion is coupled a tool to a tool mount of an end effector of a robotic arm. Typically, the mount-engagement portion is coupled to a tool via a tool-coupling cavity of the mountengagement portion. The mount-engagement portion typically includes a pair of levered arms that are hingedly coupled to each other, about a set of one or more hinges. Tools are reversibly coupled to the tool mount by the levered arms being pivoted with respect to each other such as to close around the tool mount. For some applications, the mount-engagement portion includes one or more mating portions. Typically, the arms are spring loaded such that the arms are biased toward their closed positions.

For some applications, a set of tools is provided, each of which is coupled to the mountengagement portion for engaging a tool mount of an end effector. For some applications, the set of tools comprises a universal tool kit for use with the robotic unit that includes all tools that are typically used in a cataract procedure, a different ophthalmic procedure, and/or a different microsurgical procedure. For example, the set of tools typically includes one or more of the following tools: a keratome blade, an eye fixator, a paracentesis knife, a dispersive ophthalmic viscosurgical device (OVD) syringe, a cohesive ophthalmic viscosurgical device (OVD) syringe, a staining syringe (e.g., for staining the anterior lens with a stain such as trypan blue ophthalmic solution), a lidocaine syringe, forceps, a hydrodissection syringe, a phacoemulsification probe, a chopper, an irrigation/aspiration probe, an intraocular lens injector, an antibiotics syringe, and/or a Limbal Relaxing Incision (LRI) knife.

Typically, tools are reversibly coupled to tool mount by the levered arms being pivoted with respect to each other such as to close around the tool mount. In order to exchange tools that are coupled to the tool mount, a first tool is removed from the tool mount and a second tool is then placed upon the tool mount using the levered arms of the mount-engagement portions of the respective tools. For some applications, the mount-engagement portion includes grips (e.g., grooves) to facilitate levering of the levered arms and to thereby facilitate tool exchange by a human operator. For some applications, tool exchange using the mount-engagement portion is performed automatically, e.g., using a tool rack, as described in further detail hereinbelow. Typically, whether the tool exchange is performed manually by the operator or in an automated manner, the tool exchange is performed relatively rapidly (e.g., in less than 10 seconds, or less than 5 seconds), since the removal of the first tool and the coupling of the second tool are performed in a relatively straightforward manner, by pivoting the levered arms with respect to each other. Since there are typically many such tool exchanges over the course of a procedure (e.g., a cataract procedure), this typically reduces the time that the procedure takes relative to procedures that rely upon alternative, more cumbersome techniques for tool exchange.

Typically, a sterile drape is placed around the end effector such that the sterile drape is held in place by the tool mount. As described in further detail hereinbelow, any rotation of the tool is typically effected by rotating the end effector, rather than rotating the tool with respect to the end effector. Typically, in such cases, all of the motion-driving portions of the robotic unit (such as motors, gear wheel, etc.) that are configured to drive the end effector to move, as well as the end effector itself, are disposed within a non-sterile zone on a first side of the sterile drape (i.e., on the side of the sterile drape on which the arms of the robotic unit are disposed). The mount-engagement portion is coupled to the tool mount, and the sterile drape is held in place by the tool mount, such that the end effector is disposed within a non-sterile zone on a first side of the sterile drape and the mount-engagement portion and the tool are disposed within a sterile zone on a second side of the sterile drape. There is therefore provided, in accordance with some applications of the present invention, apparatus for performing robotic microsurgery on a portion of a body of a patient, the apparatus including: a robotic system including an end effector that includes a tool mount; a plurality of tools having different functions from each other, each of the tools defining a mount-engagement portion that includes a pair of levered arms that are hingedly coupled to each other, the tools being configured to be reversibly coupled to the tool mount by the levered arms being pivoted with respect to each other such as to close around the tool mount.

In some applications, the levered arms are spring-loaded such that they are biased toward their closed positions.

In some applications, the levered arms are configured to be pivoted with respect to each other by a user.

In some applications, the apparatus further includes a sterile drape that is configured to be held by the tool mount such that, when a given tool is coupled to the tool mount, the end effector is disposed within a non-sterile zone on a first side of the sterile drape and the mountengagement portion and the tool are disposed within a sterile zone on a second side of the sterile drape.

In some applications, the mount-engagement portion includes one or more mating portions that are configured to mate with a portion of the tool mount.

In some applications, the mount-engagement portion includes a male mating portion, the tool mount includes a female mating portion, and the male mating portion is configured to mate with the female mating portion.

In some applications, the mount-engagement portion includes protrusions, the tool mount defines indentations, and the protrusions of the mount engagement portion are configured to mate with the indentations of the tool mount.

In some applications, the mount-engagement portion includes a male mating portion, the tool mount includes a female mating portion, and the male mating portion is configured to mate with the female mating portion, and the protrusions of the mount-engagement portion include angled surfaces that are oriented such that, as the levered arms close, the angled surface pull the male mating portion into the female mating portion.

In some applications, the levered arms are configured to be automatically pivoted with respect to each other automatically. In some applications, the apparatus further includes a tool rack that defines first and second sets of pegs, and the levered arms of the mount-engagement portion of each of the tools define respective holes that are configured to be placed on a pair of pegs that are adjacent to each other and that belong respectively to the first set and the second set of pegs.

In some applications, the tool rack includes first and second rails, the first and second sets of pegs are disposed respectively on the first and second rails, and the levered arms of the mount-engagement portion of each of the tools are configured to be pivoted with respect to each other by the first and second rails being moved with respect to each other such that pair of pegs are moved with respect to each other.

In some applications, a given tool of the plurality of tools is configured to be mounted on the tool mount by the tool mount being placed between the levered arms of the mountengagement portion of the given tool while the levered arms of the of the mount-engagement portion of the given tool are in open positions with respect to each other.

There is further provided, in accordance with some applications of the present invention, apparatus for performing robotic microsurgery on a portion of a body of a patient using a tool, the apparatus including: a robotic unit including: an end-effector; a tool mount coupled to the end effector and configured to hold the tool, such that tool is not coaxial with the end-effector; at least one motor configured to rotate the end effector about a longitudinal axis of the end effector, such that the tool moves from a first circumferential position with respect to the end effector to a second circumferential position with respect to the end effector; and a circular tool-actuation element that is configured to push a portion of the tool axially along a longitudinal axis of the tool, both when the tool is in the first circumferential position with respect to the end effector and when the tool is in its second circumferential position with respect to the end effector.

In some applications, the apparatus further includes a sterile drape that is configured to be held by the tool mount such that, when a given tool is coupled to the tool mount, the end effector is disposed within a non-sterile zone on a first side of the sterile drape and the tool is disposed within a sterile zone on a second side of the sterile drape. In some applications, the tool-actuation element includes a bearing that is configured to permit rotation of the tool around the circumference of the tool-actuation element while a surface of the bearing maintains pressured contact with the tool, while rotating with the tool.

In some applications, the tool-actuation element is configured to push the portion of the tool axially along the longitudinal axis of the tool, such that the portion of the tool moves axially with respect to the tool mount and the end effector, and while another portion of the tool is held, by the tool mount, in a fixed axial position with respect to the end effector.

In some applications, the apparatus further includes a tool-actuation motor that is configured to drive the tool-actuation element to move axially, the tool-actuation motor is disposed such that its longitudinal axis is parallel with the longitudinal axis of the end effector, and such that it is oriented in the direction of the tool tip.

In some applications, the tool defines a mount-engagement portion that includes a pair of levered arms that are hingedly coupled to each other, the tool being configured to be reversibly coupled to the tool mount by the levered arms being pivoted with respect to each other such as to close around the tool mount.

There is further provided, in accordance with some applications of the present invention, apparatus for performing robotic microsurgery on an eye of a patient using one or more tools, the apparatus including: at least one robotic unit including: an end effector; a tool mount coupled to the end effector and configured to securely hold the one or more tools; and a robotic arm coupled to the end effector and configured to rotate the end effector through one or more angular rotations; an XYZ platform configured move the robotic arm along X and Y directions within an XY plane, and along a Z direction that is perpendicular to the XY plane, the robotic unit being configured to move the tool through an angular rotation with respect to the patient’s eye by moving the robotic arm along at least one of the X, Y, and Z directions and by the robotic arm rotating the end effector through an angular rotation.

In some applications, the at least one robotic unit includes first and second robotic units including, respectively, first and second robotic arms, and the XYZ platform includes: first and second Z-direction sliders that support the first and second robotic arms respectively, and that are configured to slide respectively along first and second Z-direction rails; first and second X-direction sliders that support the first and second Z-direction rails respectively, and that are configured to slide respectively along first and second X-direction rails; and first and second Y-direction rails.

In some applications, the first and second X-direction rails are configured to slide along the first and second Y-direction rails respectively, and the first and second X-direction rails are configured to be slidable along the first and second Y-direction rails such that the first and second X-direction rails are adjacent to each other, such that the first and second tools mounts are capable of holding the first and second tools at angles of between 0 and 180 degrees with respect to each other.

In some applications, the robotic arm includes the robotic arm includes a yaw motor, which is configured to rotate the end effector through yaw angular rotation, a pitch motor, which is configured to rotate the end effector through pitch angular rotation, and a roll motor, which is configured to rotate the end effector through roll angular rotation about an axis of the end effector.

In some applications, the end effector includes a band and the yaw motor is configured to effect the yaw angular rotation via the band.

In some applications, the end effector includes an anti-backlash motor and an antibacklash band, and the anti-backlash motor is configured to apply a force to the end effector via the anti-backlash band that opposes the angular rotation applied to the end effector via the yaw motor.

In some applications, the anti-backlash motor is configured to maintain the antibacklash band at a constant tension throughout all yaw angular rotation of the end effector.

In some applications, the anti-backlash motor includes DC motor that is configured to yield a torque that is proportional to current, such that by fixing the current that is applied to the motor, a constant torque is maintained.

In some applications, the robotic unit is configured to move the tool around the circumference of the eye via yaw angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform. In some applications, the robotic unit is configured to move the tool through 360 degrees around the circumference of the patient’s eye.

In some applications, the robotic unit is configured to adjust a pitch of the tool with respect to the patient’ s eye via pitch angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform.

In some applications, the robotic unit is configured to move the tool from a pitch angle of minus 10 degrees to a pitch angle of plus 180 degrees relative to a normal to a cornea of the patient’s eye at a center of a pupil of the patient’s eye.

There is further provided, in accordance with some applications of the present invention, apparatus for performing robotic microsurgery on an eye of a patient using two or more tools, the apparatus including: at least one robotic unit including: a first robotic arm coupled to a first end effector and a first tool mount coupled to the first end effector and configured to securely hold a first one of the two or more tools; and a second robotic arm coupled to a second end effector and a second tool mount coupled to the second end effector and configured to securely hold a second one of the two or more tools; and at least one XYZ platform including: first and second Z-direction sliders that support the first and second robotic arms respectively, and that are configured to slide respectively along first and second Z- direction rails; first and second X-direction sliders that support the first and second Z-direction rails respectively, and that are configured to slide respectively along first and second X- direction rails; and first and second Y-direction rails, the first and second X-direction rails are configured to slide along the first and second Y-direction rails respectively, and the first and second X-direction rails are configured to be slidable along the first and second Y -direction rails such that the first and second X-direction rails are adjacent to each other, such that the first and second tools mounts are capable of holding the first and second tools at angles of between 0 and 180 degrees with respect to each other. In some applications, the first and second X-direction rails are configured to be slidable along the first and second Y -direction rails such that the first and second X-direction rails are adjacent to each other, and such that a distance between the centers of the first and second robotic arms is less than 2 cm.

In some applications, the first and second X-direction rails are configured to be slidable along the first and second Y-direction rails such as to permit a procedure to be performed either with the first and second tools disposed at approximately 90 degrees from each other, or with the first and second tools disposed at approximately 180 degrees from each other.

In some applications, the robotic unit is configured to move each of the tools through an angular rotation with respect to the patient’s eye by moving a given one of the robotic arms that is holding the tool along at least one of the X, Y, and Z directions and by the robotic arm rotating the end effector of the given robotic arm through an angular rotation.

In some applications, the given robotic arm includes a yaw motor, which is configured to rotate the end effector through yaw angular rotation, a pitch motor, which is configured to rotate the end effector through pitch angular rotation, and a roll motor, which is configured to rotate the end effector through roll angular rotation about an axis of the end effector.

In some applications, the robotic unit is configured to move the tool around the circumference of the eye via yaw angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform.

In some applications, the robotic unit is configured to move the tool through 360 degrees around the circumference of the patient’s eye.

In some applications, the robotic unit is configured to adjust a pitch of the tool with respect to the patient’ s eye via pitch angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform. In some applications, the robotic unit is configured to move the tool from a pitch angle of minus 10 degrees to a pitch angle of plus 180 degrees relative to a normal to a cornea of the patient’s eye at a center of a pupil of the patient’s eye.

The present invention will be more fully understood from the following detailed description of applications thereof, taken together with the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1A is a block diagram showing components of a robotic system that is configured for use in a microsurgical procedure, such as intraocular surgery, in accordance with some applications of the present invention;

Fig. IB is a schematic illustration of a control component unit that is used with the robotic system, in accordance with some applications of the present invention;

Figs. 1C, ID, and IE are schematic illustrations of a robotic unit of the robotic system, in accordance with some applications of the present invention;

Figs. 2A and 2B are schematic illustrations of respective embodiments of a mountengagement portion for coupling a tool to a tool mount of an end effector of a robotic arm, in accordance with some applications of the present invention;

Fig. 3A and 3B are schematic illustrations of an XYZ platform and robotic arms of a robotic unit, in accordance with some applications of the present invention;

Fig. 3C is a schematic illustration of an end effector of a robotic arm of a robotic unit, in accordance with some applications of the present invention;

Figs. 4A, 4B, and 4C are schematic illustrations of respective steps in the motion of a tool around the circumference of a patient’s eye, in accordance with some applications of the present invention;

Fig. 5 is a schematic illustration of how the angular pitch motion of a tool with respect to a patient’s eye is achieved, in accordance with some applications of the present invention;

Figs. 6A, 6B, 6C, 6D, and 6E are schematic illustrations of a tool rack for facilitating automated rapid exchange of tools for use with a robotic unit, in accordance with some applications of the present invention; and Fig. 7A and 7B are schematic illustrations of a tool being mounted on a tool mount of an end effector of a robotic arm in an automated manner, in accordance with some applications of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Reference is now made to Fig. 1A, which is a block diagram showing components of a robotic system 10 that is configured for use in a microsurgical procedure, such as intraocular surgery performed on an eye 14 of a patient 12 (eye and patient shown in Figs. 1C-D), in accordance with some applications of the present invention. Typically, when used for intraocular surgery, robotic system 10 includes a robotic unit 20, in addition to an imaging system 22, a user interface 24 (e.g., a display) and a control component unit 26 (e.g., a pair of control components, as shown in Fig. IB), via which a user (e.g., a healthcare professional, such as an ophthalmic surgeon) is able to control robotic units 20. Typically, robotic system 10 includes one or more computer processors 28, via which components of the system and a user (e.g., a healthcare professional) operatively interact with each other.

Reference is now made to Fig. IB, which is a schematic illustration of a first user 25 (e.g., a healthcare professional, such as an ophthalmic surgeon) controlling the robotic unit of the robotic system using control component unit 26, in accordance with some applications of the present invention. Typically, movement of portions of the robotic unit (and/or control of other aspects of the robotic system) is at least partially controlled by the user. For example, the user may receive images of the patient's eye and the robotic unit, and/or tools disposed therein, via user interface 24. Typically, such images are acquired by imaging system 22. For some applications, imaging system 22 is a stereoscopic imaging device and user interface 24 is a stereoscopic display. Based on the received images, the user typically performs steps of the procedure. For some applications, the user provides commands to the robotic unit via control component unit 26. Typically, such commands include commands that control the position and/or orientation of tools that are disposed within the robotic units, and/or commands that control actions that are performed by the tools. For example, the commands may control a blade, a phacoemulsification tool (e.g., the operation mode and/or suction power of the phacoemulsification tool), forceps (e.g., opening and closing of forceps), an intraocular-lens- manipulator tool (e.g., such that the tool manipulates the intraocular lens inside the eye for precise positioning of the intraocular lens within the eye), and/or injector tools (e.g., which fluid (e.g., viscoelastic fluid, saline, etc.) should be injected, and/or at what flow rate). Alternatively or additionally, the operator may input commands that control the imaging system (e.g., the zoom, focus, orientation, and/or XYZ positioning of the imaging system).

For some applications, robotic unit 26 includes first and second robotic arms and corresponding first and second end effectors, each of which is configured to hold tools 21 (as shown in Fig. 1C, for example). Typically, each set of robotic arm and end effector is configured to perform actions that are performed by a respective one of the surgeon's hands. Further typically, the robotic system includes control component unit 26, which typically includes a pair of control components 70, with each of the control components typically being configured to control actions of a respective set of robotic arm and end effector. Typically, each of the control components is a control-component arm that includes a plurality of links that are coupled to each other via joints. For some applications, the control-components are configured to hold respective control-component tools 71 therein (in order to replicate the arms of the robotic units), as shown in Fig. IB. Typically, the computer processor determines the XYZ location and orientation of the tip of the control-component tool 71, and drives the corresponding robotic arm and end effector such that the tip of the actual tool that is being used to perform the procedure tracks the movements of the tip of the control-component tool.

Reference is now made to Figs. 1C, ID, and IE, which are schematic illustrations of robotic unit 20 of robotic system 10, in accordance with some applications of the present invention. (It is noted that in Figs. ID and IE, imaging system 22 is not shown. This is for illustrative purposes, such that the imaging system does not obscure other elements within these figures.) As described with reference to Fig. IB, for some applications a first user 25 (e.g., a first healthcare professional, such as an ophthalmic surgeon) controls movement of portions of the robotic unit using control component unit 26. For some applications, an additional user 25A (e.g., a second healthcare professional, such as a nurse) is positioned closer to the robotic unit (and typically behind a desk 27), and performs actions such as exchanging tools that are coupled to the end effectors. Typically, the robotic unit includes first and second robotic arms 30, both of which are disposed on an XYZ platform 32. The robotic arms are typically configured to rotate tools that are coupled to an end effector 34 through pitch and yaw rotations, as described in further detail hereinbelow. For some applications, the robotic arms are configured to roll the end effector, so as to roll the tool, as described in further detail hereinbelow. For some applications, the robotic arms are additionally configured to push a portion of a tool axially using a tool-actuation element 36 (shown in Fig. ID), as described in further detail hereinbelow. For some applications, the XYZ platform is configured to move the robotic arms along X and Y directions within an XY plane, and along a Z direction that is perpendicular to the XY plane, as describe in further detail hereinbelow.

Figs. 1C, ID, and IE show respective set-ups of the operating room, Fig. 1C showing the additional user sat to the left of the patient with the X-direction platform of the XYZ platform being along the length of the patient’s body, Fig. ID showing the additional healthcare professional sat to the right of the patient with the X-direction platform of the XYZ platform being along the length of the patient’s body, and Fig. IE showing the additional healthcare professional sat behind the patient’s head with the X-direction platform of the XYZ platform being across the width of the patient’s body. Fig. IE shows the XYZ platform on the right side of the patient, for a procedure that is to be performed on the right eye. For a procedure that is performed on the left eye, the XYZ platform is typically disposed on the left side of the patient.

Reference is now made to Figs. 2A and 2B, which are schematic illustrations of respective embodiments of mount-engagement portion 40 for coupling a tool 21 to a tool mount 44 of an end effector 34 of a robotic arm 30, in accordance with some applications of the present invention. It is noted that Fig. 2B shows tool mount 44 in the absence of other portions of end effector 34 for illustrative purposes. Typically, the mount-engagement portion is coupled to a tool via a tool-coupling cavity 46 of the mount-engagement portion. The mount-engagement portion typically includes a pair of levered arms 48 that are hingedly coupled to each other, about a set of one or more hinges 50. Tools are reversibly coupled to tool mount 44 by the levered arms being pivoted with respect to each other such as to close around the tool mount. For some applications, the mount-engagement portion includes one or more mating portions. For example, the mount-engagement portion may include a male mating portion 52, which mates with a female mating portion 54 of the tool mount. (Female mating portion 54 is not visible in Figs. 2A or 2B.) Alternatively or additionally, the mount-engagement portion includes protrusions 56 which mate with indentations 58 on the tool mount. For some applications, protrusions 56 have an angled top surface (for example, an angle of between 1 and 20 degrees, or between 6 and 10 degrees). The angled top surface is typically oriented such that, as the levered arms close, male mating portion 52 is pulled into female mating portion 54. Typically, the arms are spring loaded such that the arms are biased toward their closed positions.

For some applications, a set of tools is provided, each of which is coupled to a mountengagement portion for engaging a tool mount of an end effector. For some applications, the set of tools comprises a universal tool kit for use with the robotic unit that includes all tools that are typically used in a cataract procedure, a different ophthalmic procedure, and/or a different microsurgical procedure. For example, the set of tools typically includes one or more of the following tools: a keratome blade, an eye fixator, a paracentesis knife, a dispersive ophthalmic viscosurgical device (OVD) syringe, a cohesive ophthalmic viscosurgical device (OVD) syringe, a staining syringe (e.g., for staining the anterior lens with a stain such as trypan blue ophthalmic solution), a lidocaine syringe, forceps, a hydrodissection syringe, a phacoemulsification probe, a chopper, an irrigation/aspiration probe, an intraocular lens injector, an antibiotics syringe, and/or a Limbal Relaxing Incision (LRI) knife.

As described hereinabove, tools are reversibly coupled to tool mount 44 by the levered arms being pivoted with respect to each other such as to close around the tool mount. In order to exchange tools that are coupled to the tool mount, a first tool is removed from the tool mount and a second tool is then placed upon the tool mount using the levered arms of the mountengagement portions of the respective tools. For some applications, the mount-engagement portion includes grips 60 (e.g., indentations and/or grooves) to facilitate levering of the levered arms and to thereby facilitate tool exchange by a human operator, e.g., additional user 25A. (It is noted that the grips as shown in Fig. 2B differ from those shown in Fig. 2A. The scope of the present disclosure includes any design of such grips, as would be apparent to a person of ordinary skill in the art upon reading the present disclosure.) For some applications, tool exchange using the mount-engagement portion is performed automatically, e.g., using a tool rack 110 (shown in Figs. 6A-E), as described in further detail hereinbelow. Typically, whether the tool exchange is performed manually by the operator or in an automated manner, the tool exchange is performed relatively rapidly (e.g., in less than 10 seconds, or less than 5 seconds), since the removal of the first tool and the coupling of the second tool are performed in a relatively straightforward manner, by pivoting the levered arms with respect to each other. Since there are typically many such tool exchanges over the course of a procedure (e.g., a cataract procedure), this typically reduces the time that the procedure takes relative to procedures that rely upon alternative, more cumbersome techniques for tool exchange.

Still referring to Fig. 2A, as shown, typically a sterile drape 62 is placed around the end effector such that the sterile drape is held in place by the tool mount. As described in further detail hereinbelow, any rotation of the tool is typically effected by rotating the end effector, rather than rotating the tool with respect to the end effector. Typically, in such cases, all of the motion-driving portions of the robotic unit (such as motors, gear wheel, etc.) that are configured to drive the end effector to move, as well as the end effector itself, are disposed within a non- sterile zone on a first side of the sterile drape (i.e., on the side of the sterile drape on which the arms of the robotic unit are disposed). The mount-engagement portion is coupled to the tool mount, and the sterile drape is held in place by the tool mount, such that the end effector is disposed within a non-sterile zone on a first side of the sterile drape and the mount-engagement portion and the tool are disposed within a sterile zone on a second side of the sterile drape. The sterile drape is not shown in other figures, in order not to obscure additional features of the apparatus.

Reference is now made to Fig. 3 A and 3B, which are schematic illustrations of robotic arms 30 and XYZ platform 32 of robotic unit 20, in accordance with some applications of the present invention. As described hereinabove, for some applications, the XYZ platform is configured to move the robotic arms along X and Y directions within an XY plane, and along a Z direction that is perpendicular to the XY plane, with the X, Y, and Z directions being indicated in Figs. 3 A and 3B. As shown in Figs. 3 A and 3B, the XYZ platform (and the operating room in Fig. 3B) is set up in the same general configuration as that shown in Fig. IE (i.e., with the additional healthcare professional sat behind the patient’s head with the X- direction platform of the XYZ platform being across the width of the patient’s body), however other set-ups are included within the scope of the present disclosure, as described hereinabove. Fig. 3A shows the XYZ platform in the absence of surrounding apparatus (such as the operating table, the imaging system), the patient and the additional user, for illustrative purposes. Fig. 3B shows the XYZ platform together with the surrounding apparatus (such as the operating table, imaging system 22) as well as patient 12 and the additional user 25A.

Typically, each of the robotic arms extends from a Z-direction slider 68, which is slidable along a Z-direction rail 72. In turn, the Z-direction rail is supported upon an X-direction slider 74, which is slidable along an X-direction rail 76. The two X-direction rails (corresponding to the two robotic arms) are typically slidable along Y-direction rails 80. For some applications a first end of the X-direction rail is supported by a Y-direction slider 78, which is actively slid along Y-direction rail 80, while a second end of the X-direction rail is supported by a rail-support slider 82, via which the second end of the X-direction rail is slide along Y-direction support rail 84. With reference to Figs. 3A-B, it is noted that the X-direction rails are capable of sliding such that they are adjacent to each other, and even with the edges of the two X-direction sliders 74 touching each other. In this regard, it is noted that the first and second robotic arms may be disposed at different Z positions from each other, such as to facilitate the X-direction rails being positioned adjacent to each other. In these positions, the two robotic arms are disposed a short distance from each other along the Y-direction, e.g., such that the distance between the centers of the two robotic arms is less than 2 cm, e.g., less than 1 cm. As described in further detail hereinbelow, the ability of the XYZ platform to place the robotic arms at such a short distance from each other, together with the angular rotation capabilities of the end effector, allow the two robotic arms to hold respective tools such that the tools are disposed at angles of anywhere between 0 degrees and 180 degrees from each other. Thus, a procedure can be performed either with the two tools disposed at approximately 90 degrees from each other, or with the two tools disposed at approximately 180 degrees from each other, both of which orientations of the tools with respect to each other are common in ophthalmic surgery.

Reference is now made to Fig. 3C, which is a schematic illustration of a robotic arm 30 and an end effector 34 of robotic unit 20, in accordance with some applications of the present invention. Typically, the robotic arm includes a yaw motor 90, which is configured to rotate the end effector through yaw angular rotation, a pitch motor 92, which is configured to rotate the end effector through pitch angular rotation, and a roll motor 94, which is configured to rotate the end effector through roll angular rotation about the axis of the end effector. For some applications, the yaw motor effects the yaw angular rotation via a band 96.

For some applications, the end effector includes an anti-backlash motor 98 and an antibacklash band 100. Typically, the anti-backlash motor applies a force to the end effector via the anti-backlash band that opposes the angular rotation applied to the end effector via the yaw motor 90. Typically, the anti-backlash motor is configured to maintain the anti-backlash band at a constant tension throughout all of the yaw angular motion of the end effector. Typically, the anti-backlash motor is a DC motor that is configured to yield a torque that is proportional to current, such that by fixing the current that is applied to the motor, a constant torque is maintained. For some applications, as an alternative to using an anti-backlash motor and antbacklash band, an anti-backlash spring is used. However, common springs will not yield a constant tension, but rather one that varies linearly with motion, such that an optimal tension is not applied by the spring. Therefore, for some applications, a constant-force spring is used, such that a constant torque is applied.

Still referring to Fig. 3C, for some applications, the end effector includes a toolactuation element 102 and a tool-actuation motor 104. Typically, the tool-actuation element is configured to push a portion of the tool axially along a longitudinal axis of the tool (by the toolactuation element being driven to move axially by the tool-actuation motor). Typically, toolactuation element pushes a portion of the tool axially along the longitudinal axis of the tool, such that the portion of the tool moves axially with respect to the tool mount and the end effector, while another portion of the tool is held in a fixed axial position with respect to the end effector, by the tool mount. For example, the tool-actuation element may push the plunger of a syringe distally in order to inject a substance into the patient’s eye and/or the tool -actuation element may actuate forceps via axial motion of the tool-actuation element.

Typically, the tool mount holds the tool such that tool is not coaxial with the endeffector. This is because the tool mount extends radially from the longitudinal axis of the end effector and the mount-engagement element extends radially from the longitudinal axis of the tool, such that when the mount-engagement element is coupled to the tool mount, the longitudinal axis of the tool is not aligned with the longitudinal axis of the end effector. Also as described hereinabove, roll motor 94 typically rotates the end effector through roll angular rotation about the longitudinal axis of the end effector. Since the tool is not coaxial with the end-effector, as the end effector is rolled about its own axis, the tool moves from a first circumferential position with respect to the end effector to a second circumferential position with respect to the end effector. Therefore, for some applications, the tool-actuation element is configured to push a portion of the tool axially along a longitudinal axis of the tool irrespective of the circumferential position of the tool with respect to the end effector. For some applications, as shown, the tool-actuation element is circular. For some such applications, the circular tool-actuation element is disposed around the longitudinal axis of the end effector. For some applications, tool-actuation element 102 includes a bearing 103 which permits rotation of the tool around the circumference of the tool-actuation element 102 while a surface of the bearing maintains pressured contact with the tool, while rotating with the tool (and typically without substantial frictional forces being generated).

Typically, tool-actuation motor 104 is disposed such that its longitudinal axis is parallel with the longitudinal axis of the end effector, and such that it is oriented in the direction of the longitudinal axis of the tool (and typically the direction of the tool tip). If, by contrast, the toolactuation motor 104 was disposed such that its longitudinal axis was perpendicular with a longitudinal axis of the tool (i.e., such that it extended toward the top of Fig. 3C) or such that it extends from the end effector away from the tool tip, then certain motions of the end effector would be limited due to the tool-actuation motor colliding with the imaging system. Therefore, for some applications tool-actuation motor 104 is disposed such that its longitudinal axis is parallel with the longitudinal axis of the end effector, and such that it is oriented in the direction of the tool tip, as shown.

Reference is now made to Figs. 4A, 4B, and 4C, which are schematic illustrations of respective steps in the motion of a tool around the circumference of eye 14 of a patient 12, in accordance with some applications of the present invention. As may be observed in the transition from Fig. 4A to Fig. 4B and then to Fig. 4C, typically, the tool is moved around the circumference of the eye both via yaw angular rotation of the end effector as well as by movement of robotic arm 30 by means of XYZ platform 32. In this way, the movement of the tool is performed in a manner that mimics the movement of a tool by a human operator in that typically a human operator moves their hand through linear motions (by moving their arm and/or their body) as well as moving the tool through angular rotations (by rotating their arm and/or hand). Typically, each of the sets of robotic arm and end effector is able to move the tool through 360 degrees around the circumference of the patient’s eye in the above-described manner. As noted hereinabove with reference to Figs. 3A-B, X-direction rails 76 of the respective robotic arms are capable of sliding such that they are adjacent to each other, and even with the edges of the two X-direction sliders 74 touching each other. In these positions, the two robotic arms 30 are disposed a short distance from each other along the Y-direction, e.g., such that the distance between the centers of the two robotic arms is less than 2 cm, e.g., less than 1 cm. The ability of the XYZ platform to place the robotic arms at such a short distance from each other, together with the angular rotation capabilities of the end effector, allow the two robotic arms to hold respective tools such that the tools are disposed at angles of anywhere between 0 degrees and 180 degrees from each other. Thus, a procedure can be performed either with the two tools disposed at approximately 90 degrees from each other, or with the two tools disposed at approximately 180 degrees from each other, both of which orientations of the tools with respect to each other are common in ophthalmic surgery.

Figs. 4A-C show that the tool may be moved around the circumference of the patient’s eye through a wide range of angular motion. However, typically, once a tool has been inserted through an incision within the patient’s cornea, motion of the tool is constrained such that the entry point of the tool into the patient’s eye remain within the incision, even as the tip of the tool is moved within the patient’ s eye. For some applications, computer processor 28 calculates the constraints that should be applied to the movement of the tool based on images of the tool and the patient’s eye that are acquired using imaging system 22.

Reference is now made to Fig. 5, which is a schematic illustration showing how angular pitch motion of tool 21 with respect to a patient’s eye 14 is effected, in accordance with some applications of the present invention. It is noted that, in Fig. 5, only a single robotic arm 30 is shown, for illustrative purposes. Typically, the pitch of the tool with respect to the patient’s eye is adjusted both via pitch angular rotation of the end effector (indicated by arrow 86 in Fig. 5) as well as by movement of robotic arm 30 by means of XYZ platform 32, and specifically movement of Z-direction slider 68 along Z-direction rail 72 (illustrated by arrow 88 in Fig. 5). In this way, the movement of the tool is performed in a manner that mimics the movement of a tool by a human operator in that typically a human operator moves their hand through linear motions (by moving their arm and/or their body) as well as moving the tool through angular rotations (by rotating their arm and/or hand). Typically, each of the sets of robotic arm and end effector is able to move the tool from a pitch angle of minus 10 degrees to a pitch angle of plus 180 degrees relative to the normal to the patient’s cornea at the center of the patient’s pupil, in the above-described manner. It is noted that in some portions of ophthalmic procedures, e.g., during phacoemulsification, it is desirable to insert a tool through a patient’s cornea from an angle of -10 degrees relative to the normal to the patient’s cornea at the center of the patient’s pupil.

As described hereinabove, typically roll motor 94 is configured to rotate the end effector through roll angular rotation about the axis of the end effector. Typically, the roll motor is capable of rotating the end effector through 360 degrees about the axis of the end effector. However, for some applications, some of the motors collide with the robotic arm at certain angular positions of the end effector. Typically, roll angular rotation is performed through an angle of between 100 and 150 degrees, e.g., between 120 and 140 degrees.

Reference is now made to Figs. 6A, 6B, 6C, 6D, and 6E, which are schematic illustrations of a tool rack 110 for facilitating automated rapid exchange of tools 21 for use with robotic unit 20, in accordance with some applications of the present invention. (It is noted that in Fig. 6A, a mount-engagement portion 40 is shown alongside the tool rack for illustrative purposes. However, the mount-engagement portion 40 is not drawn to scale relative to the tool rack.) For some applications, the tool rack includes pegs 112, which are arranged into a first set of pegs 112A aligned along a first rail 114 and a second set of pegs 112B aligned along a second rail 116, with each of the pegs on the first rail being paired with, and adjacent to, a given peg on the second rail. The tool rack includes a cam 118 (shown in Figs. 6B and 6D), or a different mechanical element, that is configured to alternately move pairs of adjacent pegs closer together and then farther apart from each other, by moving the first and second rails with respect to each other. Mount-engagement portions 40 of respective tools are mounted on respective pairs of pegs. As shown in Fig. 6A, for some applications, the mount-engagement portions define peg-mounting holes 120A and 120B at the top ends of levered arms 48 that are sized and shaped such as to be placed on pegs 112A and 112B. As the pegs 112A and 112B of respective pairs are moved closer to each other (as shown in Figs. 6B and 6C), the levered arms are pivoted with respect to each other, such that the lower ends of the arms (which are typically the ends that are coupled to the tool mount) are opened. As the pegs of respective pairs are moved apart each other (as shown in Figs. 6D and 6E), the levered arms are pivoted with respect to each other, such that the lower ends of the arms (which are typically the ends that are coupled to the tool mount) are closed.

Reference is now made to Figs. 7A and 7B, which are schematic illustrations of a tool 21 being mounted on tool mount 44 of an end effector 34 of a robotic arm 30 in an automated manner, in accordance with some applications of the present invention. Fig. 7A shows an end effector 34 of a robotic arm 30 being positioned below tool rack 110, ready to receive a tool 21. As described with reference to Figs. 6A-E, in order to place a tool on the end effector, pegs 112A and 112B of respective pairs of pegs are moved closer to each other (such that the lower ends of the arms (which are typically the ends that are coupled to the tool mount) are opened, i.e., the state shown in Fig. 7A. At this stage the end effector is typically positioned such that tool mount 44 partially engages the mount-engagement portion (e.g., by male mating portion 52 of the tool-engagement portion mating with female mating portion 54 of the tool mount, as described with reference to Fig. 2A). Subsequently, pegs 112A and 112B of respective pairs of pegs are moved apart from each other (as shown in Figs. 6D and 6E), such that the lower ends of the arms (which are typically the ends that are coupled to the tool mount) are closed. Thus, the lower ends of the arms close around the tool mount, thereby fully engaging the toolengagement portion and the tool mount. The tool is then pulled off the pegs of the tool rack by movement of the end effector and/or the robotic arm. Fig. 7B shows the end effector and the tool in this state.

Although some applications of the present invention are described with reference to cataract surgery, the scope of the present application includes applying the apparatus and methods described herein to other medical procedures, mutatis mutandis. In particular, the apparatus and methods described herein to other medical procedures may be applied to other microsurgical procedures, such as general surgery, orthopedic surgery, gynecological surgery, otolaryngology, neurosurgery, oral and maxillofacial surgery, plastic surgery, podiatric surgery, vascular surgery, and/or pediatric surgery that is performed using microsurgical techniques. For some such applications, the imaging system includes one or more microscopic imaging units.

It is noted that the scope of the present application includes applying the apparatus and methods described herein to intraocular procedures, other than cataract surgery, mutatis mutandis. Such procedures may include collagen crosslinking, endothelial keratoplasty (e.g., DSEK, DMEK, and/or PDEK), DSO (descemets stripping without transplantation), laser assisted keratoplasty, keratoplasty, LASIK/PRK, SMILE, pterygium, ocular surface cancer treatment, secondary IOL placement (sutured, transconjunctival, etc.), iris repair, IOL reposition, IOL exchange, superficial keratectomy, Minimally Invasive Glaucoma Surgery (MIGS), limbal stem cell transplantation, astigmatic keratotomy, Limbal Relaxing Incisions (LRI), amniotic membrane transplantation (AMT), glaucoma surgery (e.g., trabs, tubes, minimally invasive glaucoma surgery), automated lamellar keratoplasty (ALK), anterior vitrectomy, and/or pars plana anterior vitrectomy.

Applications of the invention described herein can take the form of a computer program product accessible from a computer-usable or computer-readable medium (e.g., a non-transitory computer-readable medium) providing program code for use by or in connection with a computer or any instruction execution system, such as computer processor 28. For the purpose of this description, a computer-usable or computer readable medium can be any apparatus that can comprise, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The medium can be an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system (or apparatus or device) or a propagation medium. Typically, the computer-usable or computer readable medium is a non-transitory computer-usable or computer readable medium.

Examples of a computer-readable medium include a semiconductor or solid-state memory, magnetic tape, a removable computer diskette, a random-access memory (RAM), a read-only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD-ROM), compact disk-read/write (CD-R/W), DVD, and a USB drive.

A data processing system suitable for storing and/or executing program code will include at least one processor (e.g., computer processor 28) coupled directly or indirectly to memory elements through a system bus. The memory elements can include local memory employed during actual execution of the program code, bulk storage, and cache memories which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution. The system can read the inventive instructions on the program storage devices and follow these instructions to execute the methodology of the embodiments of the invention.

Network adapters may be coupled to the processor to enable the processor to become coupled to other processors or remote printers or storage devices through intervening private or public networks. Modems, cable modem and Ethernet cards are just a few of the currently available types of network adapters.

Computer program code for carrying out operations of the present invention may be written in any combination of one or more programming languages, including an object- oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the C programming language or similar programming languages.

It will be understood that the algorithms described herein, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer (e.g., computer processor 28) or other programmable data processing apparatus, create means for implementing the functions/acts specified in the algorithms described in the present application. These computer program instructions may also be stored in a computer-readable medium (e.g., a non-transitory computer-readable medium) that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instruction means which implement the function/act specified in the algorithms. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the algorithms described in the present application.

Computer processor 28 is typically a hardware device programmed with computer program instructions to produce a special purpose computer. For example, when programmed to perform the algorithms described with reference to the Figures, computer processor 28 typically acts as a special purpose robotic-system computer processor. Typically, the operations described herein that are performed by computer processor 28 transform the physical state of a memory, which is a real physical article, to have a different magnetic polarity, electrical charge, or the like depending on the technology of the memory that is used. For some applications, operations that are described as being performed by a computer processor are performed by a plurality of computer processors in combination with each other. It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and subcombinations of the various features described hereinabove, as well as variations and modifications thereof that are not in the prior art, which would occur to persons skilled in the art upon reading the foregoing description.

Claims

1. Apparatus for performing robotic microsurgery on a portion of a body of a patient, the apparatus comprising: a robotic system comprising an end effector that comprises a tool mount; a plurality of tools having different functions from each other, each of the tools defining a mount-engagement portion that comprises a pair of levered arms that are hingedly coupled to each other, the tools being configured to be reversibly coupled to the tool mount by the levered arms being pivoted with respect to each other such as to close around the tool mount.

2. The apparatus according to claim 1, wherein the levered arms are spring-loaded such that they are biased toward their closed positions.

3. The apparatus according to claim 1, wherein the levered arms are configured to be pivoted with respect to each other by a user.

4. The apparatus according to claim 1, further comprising a sterile drape that is configured to be held by the tool mount such that, when a given tool is coupled to the tool mount, the end effector is disposed within a non-sterile zone on a first side of the sterile drape and the mountengagement portion and the tool are disposed within a sterile zone on a second side of the sterile drape.

5. The apparatus according to any one of claims 1-4, wherein the mount-engagement portion includes one or more mating portions that are configured to mate with a portion of the tool mount.

6. The apparatus according to claim 5, wherein the mount-engagement portion comprises a male mating portion, the tool mount comprises a female mating portion, and the male mating portion is configured to mate with the female mating portion.

7. The apparatus according to claim 5, wherein the mount-engagement portion comprises protrusions, the tool mount defines indentations, and the protrusions of the mount engagement portion are configured to mate with the indentations of the tool mount.

8. The apparatus according to claim 5, wherein the mount-engagement portion comprises a male mating portion, the tool mount comprises a female mating portion, and the male mating portion is configured to mate with the female mating portion, and wherein the protrusions of the mount-engagement portion comprise angled surfaces that are oriented such that, as the levered arms close, the angled surface pull the male mating portion into the female mating portion.

9. The apparatus according to any one of claims 1-4, wherein the levered arms are configured to be automatically pivoted with respect to each other automatically.

10. The apparatus according to claim 9, further comprising a tool rack that defines first and second sets of pegs, wherein the levered arms of the mount-engagement portion of each of the tools define respective holes that are configured to be placed on a pair of pegs that are adjacent to each other and that belong respectively to the first set and the second set of pegs.

11. The apparatus according to claim 10, wherein the tool rack comprises first and second rails, wherein the first and second sets of pegs are disposed respectively on the first and second rails, and wherein the levered arms of the mount-engagement portion of each of the tools are configured to be pivoted with respect to each other by the first and second rails being moved with respect to each other such that pair of pegs are moved with respect to each other.

12. The apparatus according to claim 10, wherein a given tool of the plurality of tools is configured to be mounted on the tool mount by the tool mount being placed between the levered arms of the mount-engagement portion of the given tool while the levered arms of the of the mount-engagement portion of the given tool are in open positions with respect to each other.

13. Apparatus for performing robotic microsurgery on a portion of a body of a patient using a tool, the apparatus comprising: a robotic unit comprising: an end-effector; a tool mount coupled to the end effector and configured to hold the tool, such that tool is not coaxial with the end-effector; at least one motor configured to rotate the end effector about a longitudinal axis of the end effector, such that the tool moves from a first circumferential position with respect to the end effector to a second circumferential position with respect to the end effector; and a circular tool-actuation element that is configured to push a portion of the tool axially along a longitudinal axis of the tool, both when the tool is in the first circumferential position with respect to the end effector and when the tool is in its second circumferential position with respect to the end effector.

14. The apparatus according to claim 13, further comprising a sterile drape that is configured to be held by the tool mount such that, when a given tool is coupled to the tool mount, the end effector is disposed within a non-sterile zone on a first side of the sterile drape and the tool is disposed within a sterile zone on a second side of the sterile drape.

15. The apparatus according to claim 13, wherein the tool-actuation element comprises a bearing that is configured to permit rotation of the tool around the circumference of the toolactuation element while a surface of the bearing maintains pressured contact with the tool, while rotating with the tool.

16. The apparatus according to claim 13, wherein the tool-actuation element is configured to push the portion of the tool axially along the longitudinal axis of the tool, such that the portion of the tool moves axially with respect to the tool mount and the end effector, and while another portion of the tool is held, by the tool mount, in a fixed axial position with respect to the end effector.

17. The apparatus according to claim 13, further comprising a tool-actuation motor that is configured to drive the tool-actuation element to move axially, wherein the tool-actuation motor is disposed such that its longitudinal axis is parallel with the longitudinal axis of the end effector, and such that it is oriented in the direction of the tool tip.

18. The apparatus according to claim 13, wherein the tool defines a mount-engagement portion that comprises a pair of levered arms that are hingedly coupled to each other, the tool being configured to be reversibly coupled to the tool mount by the levered arms being pivoted with respect to each other such as to close around the tool mount.

19. Apparatus for performing robotic microsurgery on an eye of a patient using one or more tools, the apparatus comprising: at least one robotic unit comprising: an end effector; a tool mount coupled to the end effector and configured to securely hold the one or more tools; and a robotic arm coupled to the end effector and configured to rotate the end effector through one or more angular rotations; an XYZ platform configured move the robotic arm along X and Y directions within an XY plane, and along a Z direction that is perpendicular to the XY plane, wherein the robotic unit is configured to move the tool through an angular rotation with respect to the patient’s eye by moving the robotic arm along at least one of the X, Y, and Z directions and by the robotic arm rotating the end effector through an angular rotation.

20. The apparatus according to claim 19, wherein the at least one robotic unit comprises first and second robotic units comprising, respectively, first and second robotic arms, and wherein the XYZ platform comprises: first and second Z-direction sliders that support the first and second robotic arms respectively, and that are configured to slide respectively along first and second Z-direction rails; first and second X-direction sliders that support the first and second Z-direction rails respectively, and that are configured to slide respectively along first and second X-direction rails; and first and second Y-direction rails.

21. The apparatus according to claim 20, wherein the first and second X-direction rails are configured to slide along the first and second Y-direction rails respectively, and wherein the first and second X-direction rails are configured to be slidable along the first and second Y- direction rails such that the first and second X-direction rails are adjacent to each other, such that the first and second tools mounts are capable of holding the first and second tools at angles of between 0 and 180 degrees with respect to each other.

22. The apparatus according to claim 19, wherein the robotic arm comprises the robotic arm includes a yaw motor, which is configured to rotate the end effector through yaw angular rotation, a pitch motor, which is configured to rotate the end effector through pitch angular rotation, and a roll motor, which is configured to rotate the end effector through roll angular rotation about an axis of the end effector.

23. The apparatus according to claim 22, wherein the end effector comprises a band and wherein the yaw motor is configured to effect the yaw angular rotation via the band.

24. The apparatus according to claim 23, wherein the end effector comprises an antibacklash motor and an anti-backlash band, and wherein the anti-backlash motor is configured to apply a force to the end effector via the anti-backlash band that opposes the angular rotation applied to the end effector via the yaw motor.

25. The apparatus according to claim 24, wherein the anti-backlash motor is configured to maintain the anti-backlash band at a constant tension throughout all yaw angular rotation of the end effector.

26. The apparatus according to claim 25, wherein the anti-backlash motor comprises DC motor that is configured to yield a torque that is proportional to current, such that by fixing the current that is applied to the motor, a constant torque is maintained.

27. The apparatus according to claim 19, wherein the robotic unit is configured to move the tool around the circumference of the eye via yaw angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform.

28. The apparatus according to claim 27, wherein the robotic unit is configured to move the tool through 360 degrees around the circumference of the patient’s eye.

29. The apparatus according to claim 19, wherein the robotic unit is configured to adjust a pitch of the tool with respect to the patient’s eye via pitch angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform.

30. The apparatus according to claim 29, wherein the robotic unit is configured to move the tool from a pitch angle of minus 10 degrees to a pitch angle of plus 180 degrees relative to a normal to a cornea of the patient’s eye at a center of a pupil of the patient’s eye.

31. Apparatus for performing robotic microsurgery on an eye of a patient using two or more tools, the apparatus comprising: at least one robotic unit comprising: a first robotic arm coupled to a first end effector and a first tool mount coupled to the first end effector and configured to securely hold a first one of the two or more tools; and a second robotic arm coupled to a second end effector and a second tool mount coupled to the second end effector and configured to securely hold a second one of the two or more tools; and at least one XYZ platform comprising: first and second Z-direction sliders that support the first and second robotic arms respectively, and that are configured to slide respectively along first and second Z- direction rails; first and second X-direction sliders that support the first and second Z-direction rails respectively, and that are configured to slide respectively along first and second X- direction rails; and first and second Y-direction rails, wherein the first and second X-direction rails are configured to slide along the first and second Y-direction rails respectively, and wherein the first and second X-direction rails are configured to be slidable along the first and second Y-direction rails such that the first and second X-direction rails are adjacent to each other, such that the first and second tools mounts are capable of holding the first and second tools at angles of between 0 and 180 degrees with respect to each other.

32. The apparatus according to claim 31, wherein the first and second X-direction rails are configured to be slidable along the first and second Y-direction rails such that the first and second X-direction rails are adjacent to each other, and such that a distance between the centers of the first and second robotic arms is less than 2 cm.

33. The apparatus according to claim 31, wherein the first and second X-direction rails are configured to be slidable along the first and second Y-direction rails such as to permit a procedure to be performed either with the first and second tools disposed at approximately 90 degrees from each other, or with the first and second tools disposed at approximately 180 degrees from each other.

34. The apparatus according to any one of claims 31-33, wherein the robotic unit is configured to move each of the tools through an angular rotation with respect to the patient’s eye by moving a given one of the robotic arms that is holding the tool along at least one of the X, Y, and Z directions and by the robotic arm rotating the end effector of the given robotic arm through an angular rotation.

35. The apparatus according to claim 34, wherein the given robotic arm includes a yaw motor, which is configured to rotate the end effector through yaw angular rotation, a pitch motor, which is configured to rotate the end effector through pitch angular rotation, and a roll motor, which is configured to rotate the end effector through roll angular rotation about an axis of the end effector.

36. The apparatus according to claim 35, wherein the end effector comprises a band and wherein the yaw motor is configured to effect the yaw angular rotation via the band.

37. The apparatus according to claim 36, wherein the end effector comprises an antibacklash motor and an anti-backlash band, and wherein the anti-backlash motor is configured to apply a force to the end effector via the anti-backlash band that opposes the angular rotation applied to the end effector via the yaw motor.

38. The apparatus according to claim 34, wherein the robotic unit is configured to move the tool around the circumference of the eye via yaw angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform.

39. The apparatus according to claim 38, wherein the robotic unit is configured to move the tool through 360 degrees around the circumference of the patient’s eye.

40. The apparatus according to claim 34, wherein the robotic unit is configured to adjust a pitch of the tool with respect to the patient’s eye via pitch angular rotation of the end effector as well as by movement of the robotic arm by means of XYZ platform.

41. The apparatus according to claim 40, wherein the robotic unit is configured to move the tool from a pitch angle of minus 10 degrees to a pitch angle of plus 180 degrees relative to a normal to a cornea of the patient’s eye at a center of a pupil of the patient’s eye.