MXPA99004982A - Tip for one piece manual of licuefacc - Google Patents

Abstract

The present invention relates to a manual part of liquefaction, which comprises: a) a body, which has an irrigation lumen and an aspiration lumen to the irrigation lumen is external to the aspiration lumen and has a distal tip that terminates internally to the aspiration lumen, and b) a pumping chamber, attached to the irrigation lumen, this pumping chamber has a pair of electrodes that allow the electronic current to flow through the electrodes, when a surgical fluid is contained within the chamber. bomb

Description

TIP FOR ONE PIECE LICENSE MANUAL This invention relates, generally, to the field of cataract surgery and, more particularly, to a hand piece for practicing the cataract removal liquefaction technique. The human eye, in its simplest terms, functions to supply vision, transmitting light through a clear external portion, named the cornea, and focusing the image through the lens on the retina. The amount of the focused image depends on many factors, including the size and configuration of the eye and the transparency of the cornea and the lens. When age or diseases cause the lens to become less transparent, vision deteriorates due to the diminished light that can be transmitted to the retina. This deficiency in the lens of the eye is medically known as a cataract. An accepted treatment for this condition is the surgical removal of the lens and the replacement of lens function by an artificial intraocular lens ("IOL"). In the United States of America, most cataract lenses are removed by a surgical technique called phacoemulsification. During this procedure, a thin phacoemulsive cutting tip is inserted into the diseased lens and vibrated ultrasonically. The vibrating cutting tip liquefies or emulsifies the lens, so that it can be sucked out of the eye. The diseased lens, once removed, is replaced by an artificial lens. A typical ultrasonic surgical device, suitable for ophthalmic procedures, consists of an ultrasonically driven handpiece, an attached cutting point, and an irrigation cuff and an electronic control console. The manual piece assembly is attached to the control console by an electrical cable and flexible pipes. Through the electric cable, the console varies the power level transmitted by the handpiece to the attached cutting tip and the flexible tubing supplies the irrigation fluid and drives the aspiration of the fluid from the eye through the handpiece assembly. The operative part of the manual piece is a hollow resonance bar, placed centrally, or horn, directly attached to a set of piezoelectric crystals. The crystals provide the required ultrasonic vibration, necessary to drive both the horn and the attached cutting tip during phacoemulsification and are controlled by the console. The glass / horn assembly is suspended within the hollow body or cover of the handpiece by flexible assemblies. The handpiece body terminates in a reduced diameter portion or nasal cone at the distal end of the body. The nose cone is screwed externally to accept the irrigation sleeve. Similarly, the horn auger internally threads at the distal end to receive the external threads of the cutting tip. The irrigation sleeve also has an internally threaded bore, which is screwed into the external threads of the nose cone. The cutting tip is adjusted so that the tip projects only for a predetermined amount, past the open end of the irrigation sleeve. Ultrasonic handpieces and cutting tips are described more fully in US Pat. Nos. 3,589,363; US 4,223,676; US 4,246,902; US 4,493,694; US 4,515,583; US 4,589,415; US 4,609,368; US 4,869,715; US 4,922,902; US 4,989,583; US 5,154,694 and US 5,359,996, the complete contents of which are incorporated herein by reference. During use, the ends of the cutting tip and the irrigation sleeve are inserted into a small incision of predetermined width in the cornea, sclera or other location. The cutting tip is ultrasonically vibrated along its longitudinal axis into the irrigation sleeve by the crystal-driven ultrasonic horn, thus emulsifying the selected tissue in situ. The hollow hole of the cutting point communicates with the hole in the horn, which in turn communicates with the suction line from the manual part to the console. A source of reduced pressure or vacuum in the console drives or sucks the emulsified tissue from the eye through the open end of the cutting tip, the cutting tip and the horn holes and the suction line and into the collection device. The suction of the emulsified tissue is aided by an abundant or irritant saline solution, which is injected into the surgical site through a small annular gap, between the inner surface of the irrigating sleeve and the cutting tip. Recently, a new technique of cataract removal has been developed, involving the injection of hot water (approximately 45 to 105SC) or a saline solution, to liquefy or gel the hard core of the lens, thus making it possible to aspirate the liquefied lens from the eye. The aspiration is carried out with the injection of the heated solution and the injection of a relatively cold solution, thus rapidly cooling and removing the heated solution. This technique is described more fully in U.S. Pat. No. 5,616,120 (Andrew, et al.), The entire contents of which are incorporated herein by reference. The apparatus disclosed in the publication, however, heats the solution separately from the surgical handpiece. Controlling the temperature of the heated solution can be difficult, because the fluid lines feeding the handpiece are typically up to two meters long, and the heated solution can be considerably cooled as it travels along the length of the pipe. Therefore, the need continues for a surgical manual piece that can internally heat the solution used to carry out the liquefaction technique.

Brief Summary of the Invention The present invention is an improvement over the prior art, by the provision of a tip for a surgical hand piece. This tip uses at least two lumens. One lumen is used for aspiration and at least one other lumen is used to inject the heated surgical fluid to liquefy a lens with cataracts. The distal portion of the injection lumen ends just inside the suction lumen, so that the heated fluid escaping from the injection lumen is reflected away from the inner wall of the suction lumen, before entering the eye. Such an arrangement prevents the injected fluid from entering directly into the eye. The handpiece may also contain other lumens, for example, to inject a relatively cold surgical fluid. Therefore, an object of the present invention is to provide a surgical handpiece having at least two lumens. Another object of the present invention is to provide a safer tip for a surgical handpiece, having a pump chamber. Another object of the present invention is to provide a surgical handpiece having a device for delivering the surgical fluid through the handpiece in pulses and not directly entering the eye. These and other objects and advantages of the present invention will become apparent from the detailed description and the claims that follow.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a front, top, left, perspective view of the hand piece of the present invention; Figure 2 is a rear, top, right, perspective view of the hand piece of the present invention; Figure 3 is a cross-sectional view of the hand piece of the present invention, taken along a plane passing through the irrigation channel; Figure 4 is a cross-sectional view of the hand piece of the present invention, taken along a plane passing through the suction channel; Figure 5 is an enlarged, partial cross-sectional view of the hand piece of the present invention, taken in the circle 5 in Figure 4; Figure 6 is an enlarged, partial cross-sectional view of the hand piece of the present invention, taken in the circle 6 in Figure 3; Figure 7 is an enlarged cross-sectional view of the hand piece of the present invention, taken on the circle 7 in Figures 3 and 4, and showing a boiler pump of resistances; Figure 8 is a schematic, cross-sectional view of a boiler pump of the heating element, which can be used with the present invention; Figure 9 is a partial cross-sectional view, with separate parts, of a modality of the hand piece of the present invention; and Figure 10 is an enlarged cross-sectional view of an alternative tip design for use with the present invention.

Detailed Description of the Invention The hand piece 120 of the present invention generally includes a body 12 and an operative tip 16. This body 12 generally includes an external lumen 18 for irrigation and the suction attachment 20. The body 12 is similar in construction to the phacoemulsification handpieces, well known in the art, and can be made of plastic, titanium or stainless steel. As best seen in Figure 6, the operative tip 16 includes the tip / cap sleeve 26, the needle 28 and the lumen 30. This sleeve 26 can be any suitable phacoemulsification tip cap, commercially available, or the Sleeve 26 can be incorporated into other tubes as a multi-lumen tube. Needle 28 can be any commercially available hollow phacoemulsification cutter tip, such as the TURBOSONICS tip, available from Alcon Laboratories, Inc., Fort orth, Texas. The lumen 30 can be any pipe with suitable dimension, to be mounted inside the needle 28, for example a 29-gauge hypodermic needle tubing. Alternatively, as best seen in Figure 10, the lumen 30 * may be external to the needle 28 'with a distal tip 27, which terminates within the needle bore 29 28 •, near the distal tip 31 of the needle 28 '. Preferably, the lumen 30 'lies at an angle between 25 and 502 and terminates approximately 0.1 to 3.0 mm from the distal tip 31. Such an arrangement causes the fluid exiting the lumen 28' to deviate from the inner wall 33 of the needle 28 ', before going out of distal tip 31, thus reducing the force of the pressure pulse before contact with eye tissue. The force of the pulse decreases with the distance from the tip 31, consequently, the efficiency is better for the tissue that is maintained at or within the tip 31. As best seen in Figure 5, the lumen 30 is free at the end distal and is connected to the pump chamber 42 at the proximal end. The lumen 30 and the pump chamber 42 can be sealed in a fluid-tight manner by any suitable means, having a relatively high melting point, such as silver solder. The fitting 44 holds the lumen 30 within the bore 48 of the suction horn 46. This bore 48 communicates with the accessory 20, which is rotatably mounted on the horn 46 and sealed with the O-ring seal 50, to form a suction path through the horn 46 and the external accessory 20 The horn 46 it maintains inside the body 12 by the seal 56 of 0-ring, to form the irrigation lumen 52, which communicates with the irrigation lumen 18 in the door 54. As best seen in Figure 7, in a first embodiment of the present invention, the pump chamber 42 contains a relatively large pump reservoir 43, which is sealed at both ends by the electrodes 45 and 47. Electrical power is supplied to the electrodes 45 and 47 by insulated wires 49 and 51, respectively. During use, surgical fluid (eg, saline irrigation solution) enters reservoir 43 through port 55, lumen 34 and check valve 53. The electrical current (preferably RFAC) is delivered to and through the electrodes 45 and 47, due to the conductive nature of the surgical fluid. As the current flows through the surgical fluid, this surgical fluid boils. As this surgical fluid boils, it rapidly expands out of the pump chamber 42 through the door 57 and into the lumen 30 (the check valve 53 prevents the expanding fluid from entering the lumen 34). Bubbles of the expansion gas push the surgical fluid into the lumen 30 downstream of the pump chamber 42 forward. Subsequent pulses of the electric current form sequential gas bubbles that move the surgical fluid down to the lumen 30. The size and pressure of the fluid pulse obtained by the pump chamber 42 can vary varying the length, time and / or power of the electrical pulse sent to the electrodes 45 and 47 and varying the dimensions of the reservoir 43. Furthermore, the surgical fluid can be preheated before entering the pumping chamber 42. The pre-heating of the surgical fluid will decrease the power required by the chamber of pumping 42 and / or will increase the speed at which the pressure pulses can be generated. While various embodiments of the hand piece of the present invention are described, any hand piece that produces a suitable pulse force, time and frequency of lifting, can also be used. For example, any suitable hand piece that produces a pulse force of pressure between 0.03 and 3.0 grams, with a rise time between 1 and 3,000 grams / second and a frequency between 1 and 200 Beam, may be used, being most preferred between 10 and 100 Do. The pulse force of pressure and frequency can vary with the hardness of the material being removed. For example, the inventors have found that a lower frequency with a higher pulse force is more efficient in undoing and removing relatively hard nuclear material, with a higher frequency and a lower pulse force being useful in removing the softer epinuclear and cortical material. Infusion pressure, aspiration flow rate and vacuum limit are similar to current phacoemulsification techniques. As seen in Figure 8, the fluid in the reservoir 143 in the pump chamber 142 can also be heated by the use of the heating element 145, which is internal to the reservoir 143. The heating element 145 can be, for example , a coil of stainless steel wire of 76.2 microns in diameter, to which power is supplied by the power source 147. The size and pressure of the fluid pulse obtained by the pumping chamber 142 can vary by varying the length of the electrical pulse sent to the element 145 by the power source 147 and varying the dimensions of the reservoir 143. As best seen in Figures 3, 4 and 7, the surgical fluid can be delivered to the pump chamber 43 through the lumen 34 or, as seen in Figure 8, a surgical fluid may be delivered to the pump chamber 243 through the lumen 234 of the irrigation fluid, which branches to the main irrigation lumen 235, supplying surgical fluid. Cold weather to the operative site. As seen in Figure 9, the aspiration lumen 237 can be contained internally in the hand piece 10.

Any number of methods can be employed in order to limit the amount of heat produced in the eye. For example, the working cycle of the pulse train of the heated solution can be varied so that the total amount of the heated solution introduced into the eye does not vary the pulse rate. Alternatively, the suction flow rate can vary as a function of the pulse frequency, so as the pulse rate increases, the suction flow rate will increase proportionally. This description was provided for the purpose of illustration and explanation. It will be apparent to those skilled in the pertinent art that changes and modifications can be made to the invention described above, out departing from the scope or spirit. For example it will be recognized by one skilled in the art that the present invention can be combined ultrasonic and / or rotary cutting tips to increase their performance.

Claims (11)

1. CLAIMS 1. A manual piece of liquefaction, which comprises: a) a body, which has an irrigation lumen and an aspiration lumen, the irrigation lumen is external to the aspiration lumen and has a distal tip that ends internal to the lumen of aspiration; and b) a pumping chamber, attached to the irrigation lumen, this pumping chamber has a pair of electrodes that allow electrical current to flow through the electrodes, when a surgical fluid is contained within the pumping chamber.
2. 2. The handpiece of claim 1, further comprising a second irrigation lumen.
3. 3. The hand piece of claim 2, wherein the second irrigation lumen is mounted on the exterior of the body.
4. 4. The handpiece of claim 1, wherein the electric current, which flows through the electrodes, is capable of boiling the surgical fluid.
5. 5. A piece of liquefaction, which includes: a) a body, having an irrigation lumen, and an aspiration lumen, the irrigation lumen is external to the aspiration lumen and has a distal tip that terminates internally to the aspiration lumen; and b) a pumping chamber, attached to the first irrigation lumen, this pumping chamber has an internal heating element capable of boiling the surgical fluid contained within the pumping chamber.
6. 6. The handpiece of claim 5, further comprising a second irrigation lumen.
7. The handpiece of claim 6, wherein the second irrigation lumen is mounted on the exterior of the body.
8. 8. A manual piece of liquefaction, which includes: a) a body, having an irrigation lumen and an aspiration lumen, the irrigation lumen is external to the aspiration lumen and has a distal tip that terminates internal to the aspiration lumen; and b) a pumping chamber, attached to the first irrigation lumen, this pumping chamber has an external heating element, capable of boiling a surgical fluid contained within the pumping chamber.
9. 9. The handpiece of claim 8, 9. which further comprises a second irrigation lumen.
10. 10. The handpiece of claim 9, wherein the second irrigation lumen is mounted on the exterior of the body. ,
11. 11. A manual piece of liquefaction, which comprises: a) a body, having an irrigation lumen and an aspiration lumen, the irrigation lumen is external to the aspiration lumen and has a distal tip terminating internal to the aspiration lumen; and b) a pumping chamber, attached to the first irrigation lumen, this pumping chamber is capable of producing pressure pulses with i) a force between 0.03 grams and 3.0 grams, ii) a rise time between 1 gram / second and 3,000 grams / second and iii) a frequency between 1 Hz and 200 Hz.