BRPI1002828A2 - manual facofragmenter surgical device - Google Patents

Abstract

MANUAL PhacoFRAGMENTER CLRURGlO DEVICE. To perform facectomies and aid in phacofragmentation in animals, it consists of two stainless steel metallic rods with a vertical cylindrical body (Figure 1). denominated: (A) control part and (B) guide part. that have a (C) nylon or surgical steel handle inserted in the distal end of part A. (2) lower discoid body. (5) superior discoid body. It is an instrument developed with a handle that allows to immobilize and manually section the lens with cataracts in small fragments (Figure 3) through a small incision in the cornea, in several animal species. The manual device aims to perform multiple lens fragmentation with cataracts in animals. during phacoemulsification surgery. reducing the period of use of the ultrasonic power of the phacoemulsifier device. It also allows to perform facectomies on previously dislocated lenses, for consecutive aspiration through an aspiration and irrigation system.

Description

MANUAL FACOFRAGING SURGICAL DEVICE

Field of the Invention

The present invention provides a surgical device for performing facectomies and assisting in phaco-fragmentation during cataract operation in animal patients. It is an instrument developed with nylon or surgical steel handle that allows to manually immobilize and sever the lens nucleus with cataract in small fragments in several animal patients. The device in question aims to assist the fragmentation of the cataract nucleus during phacoemulsification surgeries, and to perform facectomies on previously dislocated lenses.

To understand the need for a new instrument, it is necessary to understand some concepts about cataract operation in animals. The most modern surgical technique employed for cataract removal is phacoemulsification. This procedure uses an ultrasonic instrument that emulsifies the lens, creating a vacuum that enables continuous aspiration and irrigation of lenticular fragments.

The advantages of phacoemulsification over other surgical techniques come from the possibility of making smaller incisions in the cornea, which allows better stability of intraocular structures during the surgical procedure and less damage to adjacent tissues. Small incision results in minimal healing opacification, lower degree of induced astigmatism, faster recovery, and less likelihood of suture dehiscence. Allied to this procedure is a high rate of surgical success and return to vision. However, among the disadvantages of the procedure is the high cost of the equipment, the possibility of developing postoperative uveitis (which can generate secondary glaucoma), and corneal endothelitis (due to the direct effect of ultrasound, heating and air bubbles). . Finally, there may also be spontaneous or accidental rupture of the posterior lens capsule, with subsequent vitreous extravasation and associated retinal detachment. However, complications of phacoemulsification are substantially less numerous and less severe than other techniques routinely employed in the past, such as intra and extracapsular facectomy.

The present invention is intended to minimize the aforementioned drawbacks, since the introduction of the new device (developed instrument) into the capsular bag results in a section or facofragmentation of the lens without utilizing the ultrasonic power of the phacoemulsifier apparatus. This allows both the nucleus and cortex of the cataract lens to be fragmented into as many pieces as necessary for consecutive aspiration through an aspiration and irrigation system. Otherwise, it is also possible to use the instrument to perform facectomies on previously dislocated lenses (with or without cataract) for consecutive aspiration of the remaining fragments, reducing the risk of endothelitis induced by the use of phacoemulsifier ultrasonic power near the corneal endothelium.

The developed manual facofragmenter surgical device therefore proposes the use of the instrument in association with the phacoemulsification system. In certain specific situations, lens fragmentation can be performed without the need for phacoemulsifier, followed only by consecutive aspiration and irrigation of the lenticular fragments fragmented by the device, or if necessary, manual removal of the fragments after enlargement of the corneal incision; However, very large incisions are not desirable, and it is up to the surgeon to decide on the best use of the equipment. Another advantage of the manual shredder surgical device in this case would be the significant reduction in the cost of purchasing a phacoemulsifier,

Invention History

In emerging countries in the Middle East, doctors are conducting numerous research on cataract surgery on people in order to perform new surgical procedures as efficient as those already used, but at a more affordable cost to the poor in these countries. Based on the idea of reducing costs and improving the technique, a new instrument for cataract surgery was unpublished in animals. Some prototypes of manual cataract removal devices were tested on eyes of slaughter pigs until the current proposed device could be imagined and created. The objective was to create a simple, lightweight, dynamic instrument that would allow cutting precision and ease of handling. Several previous models have been tested based on a number of previously cited medical papers. However, the facofragmenter with nylon or steel handle was the only instrument capable of fulfilling the established needs, with an extremely reduced cost. This developed instrument allows the elevation, immobilization and sectioning of the core of the lens, according to the precision of each surgeon, in small fragments, with a minimal corneal incision very close to that made in the traditional phacoemulsification.

State of the Art

Surgical cataract removal in animals has been performed primarily by phacoemulsification through a small corneal incision, close to 3.2mm. Comparatively there are many similarities between mammalian morphology, anatomy and ocular physiological functioning, differing in small details. The determining factors that show differences between the surgical process performed on people and animals, and perhaps the three most significant factors are that cataract in people is comparatively less dense and rigid than cataract in animals, particularly dogs, which makes application difficult. of all proposed fragmentation systems; the thickness of the lens-coated capsule in animals is generally thinner and more delicate than that of people, predisposing to easier capsular rupture; and finally, the inflammatory response due to surgery (called uveitis) is substantially more exacerbated in animals than in people, resulting in greater postoperative ocular inflammation.

There are hand-held devices on the market created for humans with different principles of fragmentation. A number of researches are continuing to be developed within medicine with the intention of creating new surgical devices or new utility models to aid in cataract extraction. Among the most recent instruments developed, it is possible to highlight the Akahoshi pre-chopper; widely marketed among surgeon ophthalmologists, as well as the hydroextracapsular shredder; in addition to US53201 13A; US5156607A; US3439680A; US5860985A; W003039347A2. These devices present similar forms of lens fragmentation with different principles and may present results that are now reliable in humans but uncertain in animals. The pre-chopper originally developed by Dr. Takayaku Akahoshi in 1993 brings an extremely efficient system for cataract surgical removal in people. Various instruments and techniques were developed by the inventor to deal with soft and hard cataracts. In the hands of physician Akahoshi and other large-volume surgeons, the technique seems easy. However, even the most skilled eye surgeon may encounter difficulties and abandon the technique after a few attempts at its use. The technique may present several difficulties, the surgeon may fearfully not introduce the pre-chopper deep into the nucleus and as a result the instrument is opened very superficially and the cortex is incompletely fragmented leading to loss of vision and vision. fracture control and may also result in uncontrolled anterior dislocation of lenticular fragments and accidental rupture of the lens capsule. In addition, the use of the Akahoshi instrument on very rigid lenses such as mature cataracts and hypermatures frequently observed in dogs may present a complication when attempting to introduce the pre-chopper into the lens nucleus, possibly resulting in posterior dislocation or subluxation of the lens. cataract due to weakening and rupture of the zonular ligaments.

The adaptation of these devices often does not apply to animals and may not produce scientifically proven satisfactory results as the important differences between the eyes of humans and animals; as an example resistance and lens capsule thickness, cataract lens density, inflammatory response (uveitis) secondary to the operation.

Brief Description of the Figures

Figure 1 - Schematic drawing of the instrument with handle. A: Ask for control; B: Guide piece; C: Handle inserted at distal end of part A. Numbers represent: (1) Total length of 58 mm from part A; (2) 15 mm long discoid body and (3) 15 mm diameter; (4) Total length of 51 mm of part B; (5) Diameter of the superior discoid body of 10 mm and (6) 21 mm length; (7) Hole where the strap is inserted; (8) Guide lumen cylinder lumen hole; (9) Guide end lumen end hole, where the control part is inserted with the handle; (10) Control part lumen end hole, where the handle support is inserted inside the cylinder.

Figure 2 - Representative photograph of the movements of rotation, spacing and approximation between the pieces: (A) control and (B) guide.

Figure 3 - A: Schematic drawing of an animal's eye after capsulorhexis and hydrodissection; B: Insertion of the handle with the small diameter wire; C: Controlled increase in wire diameter so that the loop engages the lens between the capsule and the cortex; D: Wrapped the lens, gentle traction for cortex section; E: Continued section in nuclear region of the lens; FeG: Fragmented the lens, the device is reinserted for new section; H: After fragmentation the lens can be aspirated or emulsified.

Detailed Description of the Invention

To manually cut the lens of animal patients, an instrument called a looped facofragmenter was developed. The attached figures 1, 2 and 3 will provide a better understanding of the instrument.

This device consists of two cylindrical body stainless steel rods, named: (A) control part and (B) guide part (Figure 1). The (A) control part has two ends, a proximal (controlled by the operator's hand) and a distal where is a (C) malleable handle. The proximal end has one (2) lower discoid body adhered to the axial axis of the cylinder; which allows the operator to perform rotational movements around its axis, and vertical approach and retraction movements; both finely controlled by the fingers (Figure 2). The distal end has the (C) loop (consisting of nylon or surgical steel with wire thickness number 5-0 and approximate circumferential diameter of 20 mm). The wire gauge and handle diameter as well as the overall length of the (1) control and (4) guide parts may vary as needed in each surgical case. For this, the surgeon may consider the maturation stage of the cataract, the animal species in question, the estimate of the density and resistance that the lens will exert to the wire during the procedure. In general, the instrument is designed to use a string ranging from 4-0 to 6-0.

The aforementioned control part is inserted into (9) the guide part. The latter has a similar hollow cylindrical shape, but large enough to maintain close contact between the cylinders, allowing individual movement of each part, similar to a catheter with its mandrel. This piece also has two ends, one (7) proximal and one (10) distal. Proximally there is a (6) cylindrical metal support that allows the operator to insert the device into the anterior chamber of the eye through the corneal incision. This end is controlled by digital manipulation, allowing rotation movements around its axis, and control of the spacing and insertion of the control part (Figure 2).

Harmonic matching of instrument parts allows for delicate, automatically intuitive control that enhances operator sensitivity for controlled lens sectioning. Similar techniques used for cataract fragmentation have recently been developed by physicians, including:

• The phaco prechop technique called Karate Prechop or Akahoshi Prechop. This technique (developed in Japan) utilizes a system consisting of two differently shaped blades that must be inserted (after capsolorhexisis) into the lens core for manual fragmentation of the lens core. This fragmentation occurs due to mechanical separation of the fragments after the cataract nucleus has been perforated. This device is widely used in people with cataracts, but in small animals, has some restrictions on the fragmentation of the nucleus. Animal patients with cataracts often have a stiffer lenticular nucleus than that of humans, which may, in the authors' opinion, result in greater difficulty in perforation and sectioning of the lens, and increased risk of capsule rupture due to exaggerated traction. The use of this instrument in animals is not reported in animal research.

• The hydro phaco technique uses a hydrodissection cannula for the fragmentation of the cataract nucleus by manually injecting a pressurized liquid jet. This procedure has not been described in small animals either, but despite the advantages observed in humans, it may (if not properly controlled by liquid jet pressure) result in accidental rupture of the lens capsule.

In this aspect, the use of the proposed device stands out. Because it has a malleable handle, it allows the handle to be inserted into the capsule bag (in the bag) to gently moose, fix and section the cataract into smaller fragments (Figure 3).

This procedure requires the use of greater amount of viscoelastic substance for mechanical protection of the corneal endothelium and maintenance of anterior chamber volume. We can associate the proposed system to the phacoemulsification technique to reduce the instrument's ultrasonic wave exposure period:

In phacoemulsification surgery, whether performed by one or two hands, after a 3.2mm clear corneal incision, capsulorhexisis, hydrodissection, and anterior viscoelastic chamber injection (Figure 3A), the loop facofragmentator can be introduced to realization of the lens section.

The introduction of the instrument requires manual control of the guide part and control part, so that the steps allow a more harmonious and functional execution:

• During insertion of the instrument into the anterior chamber through the corneal incision, the loop to be inserted should be partially retracted (Figure 3B), maintaining a sufficient diameter for safe introduction, avoiding contact with the corneal endothelium.

• Consecutively, in order to achieve a better positioning of the handle within the lens capsular bag, the control part should be slowly introduced into the anterior chamber so that the instrument handle acquires a larger circumferential diameter. At this stage, it is important for the operator to be able to coordinate approach and retract movements associated with lateral rotation movements of the control part, thus allowing the handle to engage the lens (Figure 3C). In certain situations, this step can be facilitated (in bimanual operation) by introducing a iiPinga H "guide through an auxiliary incision if the operator has difficulty positioning the strap around the lens.

• Wrapped the lens by the strap, the guide piece is positioned close to the lens, followed by continuous and controlled traction of the control part. Thus the traction exerted to reduce the diameter of the strap will result in delicate sectioning of the cortex (Figure 3D) and cataract lens core (Figure 3E), resulting in the lens being divided into two parts.

• The procedure can be repeated after removing the used handle and reinserting the instrument. However at this stage the remaining lens fragments can be lifted and sectioned individually by the same procedure described above (Figure 3F and 3G).

• Instrument operator control may require and in certain situations re-insertion of viscoelastic substance to facilitate the facofragmentation process.

· After fragmenting the lens, according to each case, the phacoemulsification or aspiration and irrigation pen (Α / I) is introduced to remove the cataract lenticular content (Figure 3H).

Claims (6)

1. MANUAL FACOFRAGING SURGICAL DEVICE, characterized by the fact that it comprises: a) a control part, which inserts into the lumen of the guide piece and includes the handle, responsible for the section and facofragmentation of the lens. b) a guide piece, which allows the surgeon to insert the device into the anterior chamber of the animal patient's eye through a pre-made corneal incision of at least 3.2 mm. MANUAL FACOFRAGING SURGICAL DEVICE according to claim 1, characterized in that (A) the control part (1) has a total length of 45 to 60 mm, has a vertical cylindrical body stainless steel rod with (7) upper hole , where is inserted the (C) handle, (10) lower hole, which characterizes the end of the lumen of the piece, (2) lower discoid body of -10 to 20 mm in length, (3) 10 to 20 mm in diameter. The length of part A may vary according to eye size and need in each animal species. MANUAL FACOFRAGING SURGICAL DEVICE according to Claims 1 and 2, characterized in that the (B) guide piece with a total length of 45 to 60 mm comprises a vertical cylindrical body stainless steel rod with (8) upper hole, (9) bottom hole that characterizes the end of the lumen of the part, where the (A) control piece with the (C) handle is inserted. It has one (5) upper discoid body 5 to 15 mm in diameter and (6) 10 to 25 mm length. The length of part A may vary according to eye size and need in each animal species. 4 4 MANUAL FACOFRAGING SURGICAL DEVICE according to claim 1, 2, and 3, characterized by (C) the handle, comprising a nylon or monofilament stainless steel wire (of varying length), and standard wire thickness number 5-0. The wire gauge and loop diameter size may vary according to the needs of each animal, but in general the instrument is designed for use within the range 4-0 to 6-0.