Surgical instruments for minimally invasive tissue aspiration

Abstract

To provide an apparatus for disruption of cataracts in lens tissue.SOLUTION: The apparatus includes: a housing; a source of pulsed laser radiation; and an optical waveguide 12. The optical waveguide is configured to transmit the pulsed laser radiation from the source of pulsed laser radiation, and is coupleable to the source of pulsed laser radiation at a proximal end of the optical waveguide to receive the pulsed laser radiation from the source of pulsed laser radiation. The apparatus also includes a driving mechanism coupled to the optical waveguide for controllably changing the position of the optical waveguide relative to a distal end of the housing.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This disclosure claims priority from U.S. Provisional Patent Application No. 62 / 564,019, entitled “Surgical instrument for minimally invasive aspiration of tissue,” filed Sep. 27, 2017, which is incorporated by reference in its entirety.

[0002] FIELD OF THE DISCLOSURE The present disclosure relates generally to devices and methods for use in cataract surgery, and more particularly to surgical laser ablation devices and methods for destroying and aspirating cataractous lens tissue. [Background technology]

[0003] Cataract surgery was developed to treat blindness caused by opacification of the lens tissue in the human eye. Although most cases of cataracts are related to the aging process, occasionally children are born with the condition, or cataracts can develop after ocular trauma or inflammation, as well as several other eye diseases. Treating cataracts on the lens tissue is one of the most frequently performed surgeries.

[0004] In modern small incision cataract surgery, ophthalmic surgeons use a handheld metal or diamond blade to incise the area where the sclera meets the cornea. The next step in cataract surgery is to remove the anterior portion of the capsule to allow access to the cataract. Once the capsule is opened, instruments can be inserted to break up and destroy the cataract prior to removal. Tools for breaking up the lens include mechanical tools such as "choppers" or forceps to disrupt the tissue, and more recently, tools with ultrasonic transducers have been used to emulsify the tissue prior to aspiration. Various disposable ultrasonic aspiration needles have been proposed, for example in US Pat. No. 5,399,363.

[0005] Devices have been proposed that use laser radiation to break down tissue via heating effects or acousto-optically generated ultrasonic energy (e.g., in U.S. Pat. No. 5,399,433). A further technique has been employed in which radiation from a very short pulsed laser, which is not well absorbed in ocular tissue, is focused inside the volume of the cataractous lens to achieve photodissection of tissue prior to aspiration. This latter technique suffers from the need for a projection system and has not been implemented in handheld instruments due to the lack of effective optical waveguide beam delivery for such short pulses.

[0006] Microsecond and long pulse Mid-IR lasers have been used to ablate lens tissue. The mechanism of laser ablation (impulsive heat deposition) is described in US Pat. No. 6,399,633 (hereby incorporated by reference in its entirety), in which rapid heating by excitation of the tissue's internal vibrational modes causes vaporization of exposed tissue. The laser source required for this new mechanism is compatible with a specific fiber optic beam delivery system.

[0007] Using the above laser mechanisms, surgical devices and methods have been proposed that can disrupt and remove lens tissue via a handheld instrument that includes a fiber optic beam delivery system for on-contact tissue destruction, see U.S. Patent Application Publication No. 2007 / 0133991, which is incorporated herein by reference in its entirety. In one embodiment of this disclosure, the distal end of the optical fiber is delivered to the tissue inside a larger diameter aspiration needle. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] US8454551 B2 [Patent Document 2] US Patent 6083192 A [Patent Document 3] US Patent 8,029,501 [Patent Document 4] WO2016041086 A1 Summary of the Invention

[0009] In some examples, the present disclosure describes an apparatus for the destruction of cataracts in lens tissue. The apparatus includes a housing; a pulsed laser radiation source; and an optical waveguide. The optical waveguide is at least partially contained within the housing and includes a flexible optical fiber. The optical waveguide is configured to transmit pulsed laser radiation to cause destruction of the cataract and is couplable at a proximal end thereof to a pulsed laser radiation source for receiving pulsed laser radiation from the pulsed laser radiation source. The apparatus also includes a drive mechanism coupled to the optical waveguide for controllably varying a position of the optical waveguide relative to a distal end of the housing.

[0010] Reference is now made, by way of example, to the accompanying drawings which illustrate example embodiments of the present application. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a partial perspective view of an example embodiment of laser ablation of cataractous lens tissue. [Diagram 2] FIG. 1 is a partial perspective view of an example embodiment of a handheld laser instrument for delivering a laser pulse source. [Diagram 3] FIG. 3 is a cross-sectional view of an example of the distal tip of the handheld laser instrument of FIG. 2, in which the aspiration needle and optical fiber are collinear and the entrance to the aspiration channel is unobstructed. [Figure 4] FIG. 3 is a cross-sectional view of an example distal tip of the handheld laser instrument of FIG. 2, in which a piece of tissue is drawn toward the aspiration channel by the negative pressure, becoming too large to be aspirated and completely blocking the entrance to the aspiration channel. [Diagram 5] FIG. 5 is a cross-sectional view of an example of the same tissue section of FIG. 4 when disrupted and aspirated, with the obstruction partially or completely removed. [Figure 6]FIG. 3 is a cross-sectional view of an example of the distal tip of the handheld laser instrument of FIG. 2 where a persistent occlusion occurs, where the laser fiber destroys all tissue within its range but is unable to eliminate the occlusion. [Figure 7] The aspirated fluid may be contained within a sterilizable or disposable tool assembly, and a cross-sectional view of an exemplary handheld laser instrument in which the distal end of the fiber can be set inside the aspiration needle to allow the inelastic optical fiber to be moved within the aspiration channel without contaminating some reusable parts of the optical fiber beam delivery. [Figure 8] FIG. 3 illustrates an example embodiment of the laser instrument of FIG. 2, the instrument shown as three separable parts: a reusable laser delivery assembly containing an optical fiber and having a fiber connector, and a removable tip handle assembly containing the distal instrument tip and having an output channel for irrigation, an aspiration needle, and an extended fiber optic tip, and also including points for connecting disposable tubing to a disposable aspiration and irrigation means. [Figure 9] FIG. 13 is an exploded view of an example of a replaceable handle assembly with a small optical fiber attached to a fiber connector that mates with a corresponding connector on a reusable laser delivery assembly. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Similar reference numbers may be used in different figures to indicate similar components.

[0013] In some examples, the present disclosure provides a handheld laser phacoemulsification device for disrupting and removing cataractous lens tissue.

[0014] In some instances, the present disclosure provides an apparatus that can help provide improved aspiration rates of a surgical instrument 54 compared to conventional instruments by utilizing laser energy to disrupt tissue upon contact with the fiber optic tip 16. The fiber optic tip 16 is collinear within a small diameter aspiration channel suitable for manual positioning in the anterior capsule of the human eye. The fiber optic 16 can be advanced or retracted within the aspiration channel to increase the rate of tissue aspiration and minimize the risk of unintentionally disrupting aspirated tissue.

[0015] In some examples, the present disclosure integrates control of fluidics (aspiration and irrigation means) and laser disruption with algorithms that adjust laser parameters such as pulse rate, envelope, and laser tip positioning based on user input and sensor output (e.g., pressure and flow measurements in the aspiration and irrigation channels, etc.) to achieve faster and more accurate aspiration with minimal fluidics (flow and vacuum) and minimal disruption to surrounding tissue.

[0016] In some examples, the present disclosure provides a surgical instrument 54 where user control of aspiration speed is further enhanced through the addition of a movable optical fiber 16 integrated within the irrigation / aspiration tip and control system algorithms that respond to various user inputs and sensed fluid conditions to automatically optimize fiber positioning and laser pulse rates to minimize invasive damage to surrounding tissue structures, limit changes in anterior capsule pressure, and minimize aspiration and irrigation flows during tissue removal procedures.

[0017] The present disclosure describes an apparatus including a laser probe that, upon contact, can efficiently drive rapid tissue decomposition within the body by optical excitation of selected vibrational modes inside the tissue's molecules on a time scale faster than thermal diffusion to the surroundings. The laser probe uses a laser mechanism similar to that previously disclosed in U.S. Patent No. 6,399,633, which is incorporated herein by reference in its entirety.

[0018] The present disclosure relates to an exemplary approach for efficiently destroying hard cataract tissue while avoiding the problem of energy propagation into other tissues of the eye.

[0019] Referring to FIG. 1, an exemplary laser ablation approach is disclosed. FIG. 1 shows an example of laser disruption of cataractous lens tissue 1. This laser disruption occurs when a laser pulse of selected duration, wavelength and pulse energy, such as that disclosed in U.S. Pat. No. 6,399,633, is coupled into an optical waveguide 12 and exits from a distal end 16 of the optical waveguide 12. The optical wavelength guide 12 is directed toward the inside of the cataractous lens tissue 1 and inserted through an incision point 7 and through an opening in the capsule 9 into the anterior chamber of the eye. The light is either strongly absorbed by the lens cells 3 or intercellular regions 8 in contact with the exit 16 of the waveguide, or irradiates a volume of tissue 5 within a distance close to the optical absorption depth 40 of the laser light inside the tissue, resulting in the destruction of the lens cells and / or cellular structures of the lens 4, and the effective disintegration and aspiration of the destroyed fragments of the cataractous tissue 6, with minimal disturbance to distant parts of the eye, such as the cornea 2 or the lens capsule 9. The hollow tube or needle 13, when connected to a means of vacuum pressure, provides a means for removing the disrupted tissue. The inner tip of the aspiration channel 52 carries the distal end of the optical fiber 16 from which emerges the laser pulse. The laser pulse disrupts tissue on contact and the resulting material can be aspirated from the eye.

[0020] This collinear delivery of laser energy is advantageous for small optical fibers and a precise laser disruption process because the tissue is actively drawn to the laser energy by suction pressure. The on-contact tissue disruption of the present disclosure is not limited to lens tissue but can be applied to all tissue types.

[0021] Notably, in one exemplary embodiment, means are provided for moving or otherwise shifting the position of the optical fiber tip 16 during a surgical procedure, and for controlling this position based on user input and fluid conditions in the irrigation and aspiration channels, see FIG. 2.

[0022] FIG. 2 discloses an exemplary embodiment of the present disclosure, in which a handheld instrument 54 is coupled to a laser pulse source 10. The laser pulse source 10 is controlled by a signal 22 from a control circuit 21, which also controls a means for aspiration 18 and a means for irrigation 17. The laser pulse source 10 further receives input from one or more sensors, such as a flow sensor 38 and a pressure sensor 48 in the fluid channel. The functions of irrigation, aspiration pressure, aspiration flow rate and laser power, pulse rate and fiber positioning can be further controlled through the use of a user input device 11, such as a multi-function foot pedal, and preset parameters stored in the control circuit 21. Other control means can also be provided. The preset parameters may include maximum flow and pressure limits, laser power limitations and other operating modes. The irrigation and aspiration channel 52 can be coupled to a flexible tube 100 (see FIG. 8), which can further be coupled to a tool assembly 19, which may be removable, reusable or disposable. A flexible tube 100 allows for insertion and control of the distal tip 20 of the tool assembly 19 inside the intraocular lens 1 to achieve controlled micro-disruption of cataract tissue at the tip, see FIG. 1. In one example, a means 24 for moving the optical fiber 12 (e.g., a drive mechanism such as a linear motor, or a linear translation mechanism driven by a rotary motor, voice coil actuator, etc.) is provided to control the relative distance of the distal optical fiber tip 16 to the distal end of the aspiration channel 52. A sensor or encoder 53 (e.g., a photoacoustic sensor, etc.) may be provided to track the position of the fiber tip. Another sensor may also be provided to detect when there is physical contact between the optical fiber 12 and tissue.

[0023] In some examples, the optical fiber 12 may be made of any suitable material, such as sapphire, diamond, ZBLAN, or YAG. The optical fiber tip 16 may be straight or may have any other suitable configuration, such as, for example, curved, tapered, or angled, as described in U.S. Patent Application Publication No. 2007 / 0139991.

[0024] The user can control the position of the optical fiber tip 16 in a number of different ways. In one example embodiment, a further user input device is provided that is configured to move the position of the fiber forward or backward. In a further example, the fiber is advanced using a proportional pedal that is commonly used in conventional procedures to increase flow / aspiration pressure. Actuation of the pedal causes a higher level of aspiration while simultaneously reducing the access of the laser disruption mechanism to the aspiration tip.

[0025] In some examples, the position of the fiber tip 16 is automatically adjusted based on the response of the pressure and flow rate in the aspiration channel 52 to a user request for a higher level of aspiration, for example by sensing the degree of occlusion at the tip. In such embodiments, the position of the fiber optic tip 16 may be determined directly by the surgeon or in combination with a control algorithm that senses the fluid conditions in the aspiration channel 52 and identifies several conditions, including occluded and unoccluded flow. In some examples, automatic adjustments may be used in combination with direct user input to control the position of the fiber optic upper end 16.

[0026] In conventional cataract surgery systems, the user controls the suction (e.g., via a foot pedal). Conventional systems may include some simple automatic controls to limit flow if the pressure is too high. In the present disclosure, a more comprehensive control of the system is provided, where the laser parameters are also controlled, taking into account the detected pressure and flow, and controlling the positioning of the optical fiber. For example, the flow may be limited because the pressure is too high, and the system controls the laser to turn on and controls the optical fiber to move distally towards the tip as a way to reduce the pressure. Further details of such comprehensive control are described below.

[0027] Referring to Figure 3, under non-blocking conditions, by considering laminar flow and Newtonian fluid inside a circular cross-section pipe, Poiseuille's law is:

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[0030] Given a user control signal for a desired aspiration flow rate, which can range from 0 to 100%, the user can expect the flow to follow the control signal up to the maximum pressure.

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[0032] With further reference to FIG. 3, insertion of an exemplary device is disclosed. FIG. 3 illustrates the distal tip of an exemplary instrument 54, where the aspiration needle 13 and the optical fiber 12 are collinear and the entrance to the aspiration channel 52 is unobstructed. The pressure in the aspiration channel 52 is low and the flow rate is not limited by pressure. In this example, the location of the fiber tip 16 is not critical and can be retracted a few mm within the aspiration needle. In some examples, the fiber tip 16 can be retracted distally up to and including about 5 mm and proximally up to and including about 10 mm. Other distances may be possible depending on the dimensions of the human eye and depending on the particular application. The laser energy used in the retracted position contributes to further destroy tissue fragments drawn into the aspiration channel 52 by the negative pressure. In this mode, the instrument 54 acts much like the tip of a conventional aspiration / irrigation instrument. Capsular bag aspiration is less likely to come into contact with the optical fiber and can be left in place during accidental aspiration.

[0033] During a surgical procedure, it may be desirable to hold a piece of tissue securely with the aspiration needle until it is properly positioned within the anterior chamber for energy destruction. When the piece is engaged with aspiration pressure, it can fill the entrance to the aspiration channel 52 and prevent further removal without increasing pressure.

[0034] 4 illustrates one such example blockage that occurs when the fiber is retracted. A piece of tissue 81 is pulled toward the aspiration channel 52 by the negative pressure and is too large to be aspirated, completely blocking the entrance to the aspiration channel 52. In this example situation, the pressure inside the aspiration channel 52 increases as a function of the flow rate, and it is advantageous to further advance the laser fiber toward the entrance to the aspiration channel 52 and destroy the tissue causing the blockage rather than attempting to aspirate at a higher pressure.

[0035] Moreover, in this exemplary embodiment, the aspiration needle can better maintain the occlusion if the fiber does not protrude, which would otherwise prevent itself from becoming embedded inside the occluding tissue fragment or from creating any occlusion. The tissue fragment is held up to the tip of the aspiration needle by the force caused by the pressure difference between the fluid around the tissue fragment and the inside of the aspiration channel 52. In this case, the relationship between pressure and flow rate deviates significantly from Poiseuille's law, as Q approaches 0, since no volume can flow through the occlusion, assuming R and L are fixed.

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[0038] By monitoring pressure and flow over time, the algorithm is able to predict occlusion when pressure is rising but flow is falling. In other words, when there is no occlusion and below the pressure and flow limits, the control signal and aspiration rate are well defined.

[0039] By control signal

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[0042] However, once occlusion occurs, further demand for flow, i.e., increasing A, does not result in further flow: Q=0 and

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[0045] Assuming that the control signal does not change while an occlusion occurs:

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[0049] However, when a blockage occurs, the initial flow rate Q0 starts to decrease to zero,

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[0056] In this example embodiment, a conventional phaco machine operator would begin to use higher vacuum pressure or ultrasound to break the occlusion.

[0057] FIG. 5 discloses one means through which the laser fiber contributes to the transition from occlusion to non-occlusion. In other words, FIG. 5 discloses the tissue fragment when broken and aspirated, the occlusion is partially or completely cleared, and the laser fiber can begin to retract until another occlusion occurs. Once the occlusion begins to clear and the pressure no longer rises dramatically with the flow rate, the laser power can be reduced or the laser tip can be retracted to prevent the remaining tissue fragment from being pushed out of the tip. The greater the occlusion, the closer the fiber should be to the blocked entrance of the aspiration channel 52.

[0058] In some examples, a simple control algorithm can be defined to determine the position of the fiber tip based on pressure alone as follows:

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[0060] In some examples, the position of the fiber can be set by the flow rate:

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[0064] FIG. 6 discloses a situation where the occlusion is persistent and cannot be eliminated within a certain time t≫τ. In this case, the position of the fiber can be made to oscillate longitudinally within the channel to increase the effective range of the precision laser disruption and add mechanical reinforcement to its action (similar to shaking the tissue). In this example, the control algorithm can assume that if the foot pedal is depressed sufficiently for a set time that is much longer than the rise time and the pressure is still at maximum, the optical fiber motion will be changed to an oscillatory mode. This is because the extended input to suction while the pressure is not being lowered may indicate that the occlusion has not been eliminated and more mechanical assistance is needed.

[0065] In further exemplary embodiments, the laser pulse rate, envelope, and fiber position are used to minimize total flow and pressure changes within the anterior capsule to achieve the least invasive tissue removal possible, and most importantly to prevent unintended capsule disruption or damage to the corneal endothelium by laser energy, mechanical forces, or fluidics. The average power of the laser pulse is a function of the pulse rate and the energy per pulse. Given a particular laser intensity threshold for laser tissue ablation, it is useful to maintain a constant pulse energy and attenuate the laser power via a reduction in the pulse rate, rather than attenuating the laser power. In the present disclosure, enhanced action of the instrument 54 occurs when the laser pulse rate is not evenly divided, but instead there are periods where the laser action is modulated by a lower frequency envelope. An envelope frequency of around 5 Hz has been found to be suitable in hardened ocular tissue. The pulse rate can be increased or decreased from 0-100% near pulse width modulation of the laser pulse at the envelope frequency.

[0066] It is hypothesized that the laser pulse superheats a volume of tissue / liquid at the fiber tip. Because the tip is rigid and the area (~200 μm) is much larger than the absorption depth (~1 μm), the irradiated material cannot expand back into the solid fiber, and there is a net force that pushes the tissue away from the fiber. This expansion force causes an increase in pressure that opposes the vacuum pressure of the aspiration pump. By pausing the laser for a while during the occlusion, the aspiration pump is allowed to build up a higher pressure, and the pressure change caused by the laser pulse is unlikely to increase enough to reverse the sign of the pressure in the aspiration channel (and cause the tissue to move away).

[0067] 7, in some examples, the fluid 72 to be aspirated may be contained within a sterilizable or disposable tool assembly 19, and the distal end of the fiber 16 may be set inside the aspiration needle 13 to allow the inelastic optical fiber to be moved within the aspiration channel while not contaminating some reusable portion of the fiber optic beam delivery 12. In some examples, this may be accomplished by a compression rubber seal 73 in which the fiber is secured to a moving shaft assembly 74. The tool assembly 19 has an irrigation channel 70 and an aspiration channel 71 that connect to a distal tip and tubing connectors that allow for flexible attachment of the means for fluidics control.

[0068] 8, in some examples, the instrument 54 includes three separable parts: a reusable laser delivery assembly 75 (including the optical fiber 12 and having a fiber connector 78); a removable tip handle assembly 76 (including the distal instrument tip 20 and having an output channel 51 for irrigation, an aspiration needle 13, and an extended fiber optic tip 16 that couples at its sagittal end to a fiber connector 78 of the reusable delivery system); and a disposable aspiration and irrigation means 100. A connection point may be provided for connecting the disposable tube 100 to the tip handle assembly 76, or the two disposable parts may be pre-assembled.

[0069] Referring to FIG. 9, an exploded view of the replaceable handle assembly 76 is disclosed. A small optical fiber 88 is attached to a fiber connector 79 that connects with a corresponding connector 78 on the reusable laser delivery assembly. The shaft assembly 82 allows the optical fiber to be sealed with a washer 73, which is pressed around the shaft assembly 82 by a threaded nut 87. The threaded nut 87 remains captured by the shaft assembly with a spring 101 that acts to retract the fiber tip when not connected to the reusable part of the assembly. A manifold 92 in which the aspiration needle 13 and distal irrigation sleeve 51 are located is coupled to the irrigation channel 70 and aspiration channel 71 of the handle assembly 19 via a manifold extension 93 and a sealing washer 96 to keep the channels separated. The fiber shaft assembly is attached to the manifold extension 93 by a shaft sealing nut 87.

[0070] As used herein, the terms "comprise" and "comprising" are to be interpreted as inclusive and open-ended, and not exclusive. Specifically, as used in the specification and claims, the terms "comprise" and "comprising" and variations thereof mean that the specified features, steps, or components are included. These terms are not to be interpreted as excluding the presence of other features, steps, or components.

[0071] The above description of the preferred embodiment of the present disclosure is presented to illustrate the principles of the present disclosure, and is not presented to limit the present disclosure to the specific embodiments illustrated. It is intended that the scope of the present disclosure be defined by all of the embodiments encompassed by the appended claims and their equivalents.

[0072] Item 1: 1. An apparatus for disrupting cataracts in lens tissue, comprising: Housing and a pulsed laser radiation source; an optical waveguide at least partially contained within the housing, the optical waveguide including a flexible optical fiber, the optical waveguide configured to transmit pulsed laser radiation to cause disruption of the cataract, the optical waveguide being couplable at a proximal end to a pulsed laser radiation source for receiving the pulsed laser radiation from the pulsed laser radiation source; a drive mechanism coupled to the optical waveguide for controllably varying a position of the optical waveguide relative to the distal end of the housing; An apparatus comprising: Item 2: 2. The apparatus of item 1, wherein the drive mechanism is controlled by a control system to position the optical fiber as a function of vacuum pressure and flow rate in the aspiration and irrigation channels of the apparatus. Item 3: 3. The apparatus of claim 1 or 2, wherein the drive mechanism is controlled by a control system to position the optical fiber in proportion to the suction level of the tissue. Item 4: 4. The apparatus of any one of claims 1 to 3, further comprising a sensor configured to sense contact between the optical fiber and tissue. Item 5: 5. The apparatus of any one of claims 1 to 4, further comprising an optical acoustic sensor for sensing the position of the optical fiber. Item 6: 5. The apparatus of any one of claims 1 to 4, further comprising an encoder for sensing a position of the optical fiber. Item 7: 7. The apparatus of any one of items 1 to 6, wherein the drive mechanism is controlled by the control system to longitudinally vibrate the optical fiber within the housing. Item 8: 8. An apparatus according to any one of items 1 to 7, wherein the pulse rate of the laser radiation is adjusted by a selected lower frequency, thereby allowing higher laser power balanced with a lower vacuum speed. Item 9: 9. The apparatus according to any one of items 1 to 8, wherein the optical fiber is made of a material selected from sapphire, diamond, ZBLAN, or YAG. Item 10: 10. The device of any one of claims 1 to 9, wherein the distal end of the flexible optical fiber is curved, tapered, or angled. Item 11: 11. The apparatus of any one of items 1 to 10, wherein the flexible optical fiber is made from an infrared-transparent optical material.

Claims

1. 1. An apparatus for disrupting wet tissue, comprising: Housing and a pulsed laser radiation source configured to provide pulsed laser radiation having a pulse duration in the range of 10 ps to 1 ns; an optical waveguide at least partially contained within the housing, the optical waveguide comprising a flexible optical fiber, the optical waveguide being coupleable at a proximal end to the pulsed laser radiation source for receiving the pulsed laser radiation from the pulsed laser radiation source, the optical waveguide being configured to deliver pulsed laser radiation at a wavelength in a range of about 2700 nm to about 3300 nm that matches an absorption peak of water, the pulse duration and the wavelength of the pulsed laser radiation being selected to provide an impulse heat deposition on the hydrated tissue; at least one of a flow sensor or a pressure sensor disposed in at least one fluid channel of the device, the at least one of the flow sensor or the pressure sensor coupled to a control system to provide to the control system at least one of a flow rate sensed by the flow sensor or a vacuum pressure sensed by the pressure sensor, respectively; a drive mechanism coupled to the optical waveguide for controllably oscillating a position of the optical waveguide relative to the distal end of the housing, the drive mechanism being controlled by the control system to oscillate the position of the optical fiber as a function of changes in vacuum pressure or as a function of relative changes in pressure and flow rate; An apparatus comprising:

2. The device of claim 1 , further comprising a sensor configured to sense contact between the optical fiber and a target tissue.

3. The apparatus of claim 1 , further comprising an optical acoustic sensor that senses the position of the optical fiber.

4. The apparatus of claim 1 , further comprising an encoder for sensing a position of the optical fiber.

5. 2. The apparatus of claim 1, wherein the control system is configured to determine that a change in the vacuum pressure or a relative change between the pressure and flow rate is indicative of an occlusion, and in response to determining that the occlusion is still indicated after a predetermined time, the drive mechanism is further controlled by the control system to vibrate the optical fiber longitudinally within the housing.

6. 10. The apparatus of claim 1, wherein the pulse rate of the laser radiation is adjusted by a selected frequency, thereby allowing laser power to be balanced with vacuum speed.

7. 10. The apparatus of claim 1, wherein the optical fiber is made of a material selected from sapphire, diamond, ZBLAN, or YAG.

8. The device of claim 1 , wherein the distal end of the optical fiber is curved, tapered, or angled.

9. The apparatus of claim 1 , wherein the optical fiber is made from an infrared-transparent optical material.

10. The apparatus of claim 1 , wherein the drive mechanism is a linear motor, a linear translation mechanism driven by a rotary motor, or a voice coil actuator.

11. 10. The device of claim 1, wherein the housing includes a reusable laser delivery portion through which the optical fiber extends and a removable tip handle from which an optical fiber tip extends, the removable tip handle being removably securable to the reusable laser delivery portion.

12. The apparatus of claim 11 , wherein the optical fiber has a distal end with a fiber connector, and the optical fiber tip has a proximal end that mates with the fiber connector.

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