Irrigation/aspiration tip

IS 2 340 101 T3

DESCRIPTION

Irrigation / aspiration tip.

The present invention relates to aspiration tips and, more particularly, to aspiration tips used in ophthalmic surgery by phacoemulsification.

Background of the invention

The human eye in its simplest terms works to provide vision by transmitting light through a transparent outer part called the cornea and focusing the image through the lens on the retina. The quality of the focused image depends on many factors including the size and shape of the eye and the transparency of the cornea and lens.

When age or disease causes the lens to be 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 surgical removal of the lens and replacement of lens function with an artificial lens.

In the United States, most cataract lenses are removed by a surgical technique called phacoemulsification. During this procedure, a thin phacoemulsification 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 aspirated out of the eye. The diseased lens, once removed, is replaced by the artificial lens.

Before the introduction of the artificial infraocular lens into the eye, softer cortical material is aspirated from the eye using an aspiration tip. Aspiration tips are similar to phacoemulsification tips, but with a smaller opening at the distal end and are not typically ultrasonically vibrated. The aspiration tip can also be used to "polish" the posterior capsule to remove residual epithelial cells and reduce the risk of posterior capsule opacification. Conventional suction tips are made of titanium or stainless steel. These tips must be highly polished to reduce burrs and eliminate sharp edges that can snag or tear the posterior capsule. However, it is very difficult to polish the aspiration hole and inner lumen of the aspiration tip, and some burrs may remain even after extensive polishing. During capsule polishing and cortical cleaning, the posterior capsule may be partially retracted into the aspiration opening and the inner lumen of the aspiration tip. If these parts of the sniffer tip contain rough edges or burrs, tearing of the posterior capsule may occur. Also, during repeated use, the exterior of the sniffer tip can develop burrs and rough spots that can snag or tear the capsule.

An anterior aspiration tip described in US Patent No. 5,718,677 (Capetan et al.) Overcomes the problems associated with metal tips by installing a silicone rubber tip cap over the distal end of the metal cannula. Although the device is effective in reducing or eliminating some of the hazards discussed above, the rubber tip cap can be attached to the metal tip to prevent the tip cap from slipping off the metal tip. Although the rubber tip cap is autoclavable, the tip cap is much more easily damaged than the metal cannula, thus limiting the number of reuses of the tip assembly. Furthermore, as with other commercially available tips and with the tip cap shown in Figures 10 and 11 of US 2003/0199883 A1, the tip cap does not provide any irrigation function, so a handpiece must be used. irrigation hose or an infusion sleeve over the suction tip.

US 2005/0234473 A1 describes a phacoemulsification probe tip with a tip protector having a tip cap arranged as a membrane covering the distal end of the probe. The membrane can wrap around the outer edges of the distal end of the probe tip and back into the tip, but without sealing the distal end of the probe.

Consequently, there continues to be a need to provide an irrigation / aspiration tip that reduces the possibility of tearing the posterior capsule during cortical cleaning and polishing of the capsule.

Brief summary of the preferred embodiment

The present invention improves on the suction tips of the prior art by providing an irrigation / suction tip according to the following claims. A relatively rigid cannula attached to a hub has an open end opposite the hub. Coaxially and removably received on the tip is an elastomeric or soft rubber sleeve. The sleeve forms a gap between the sleeve and the cannula, allowing the gap for irrigation flow. The distal end of the sleeve is closed by a reduced diameter cap. The reduced diameter of the cap seals the distal end of the cannula. The relatively soft cap reduces the likelihood of the posterior capsule tearing during cortical cleaning and capsule polishing. Removal of the sleeve allows the cannula to be resterilized an unlimited number of times, thus allowing unlimited reuse of the cannula.

IS 2 340 101 T3

An object of the present invention is to provide an irrigation / aspiration tip that reduces the likelihood of tearing the posterior capsule.

Another object of the present invention is to provide an aspiration tip having an open lumen sealed with a flexible cap.

Other objects, features and advantages of the present invention will become apparent with reference to the drawings and the following description of the drawings and claims.

Brief description of the drawings

Figure 1 is an expanded perspective view of a prior art suction tip.

Figure 2 is an enlarged cross-sectional view of the irrigation / aspiration tip of the present invention.

Figure 3 is an enlarged cross-sectional view of the irrigation / aspiration tip of the present invention.

Figure 4 is an enlarged perspective view of the irrigation / aspiration tip of the present invention installed in a handpiece.

Detailed description of the preferred embodiments

As best seen in Figure 1, a prior art aspiration tip 10 comprises an aspiration cannula 12 and a cap 14. Cannula 12 is open at distal end 18 and is attached to hub 16 at proximal end 22 The hub 16 allows the suction tip 10 to be attached to an appropriate handpiece (not shown). The distal end is sealed by a cap 14. Cap 14 is generally tubular in shape, is open at proximal end 24, and is closed at distal end 26, except for hole 20.

As best seen in Figures 2, 3, and 4, the irrigation / suction tip 100 of the present invention generally includes a suction cannula 112 and a sleeve 114. Cannula 112 is open at distal end 118 and is secured to the hub 116 at proximal end 122. Hub 116 allows aspiration tip 100 to be attached to a handpiece 140. The distal end 118 of the cannula 112 is sealed by a reduced diameter end cap 115 that is integrally formed into the distal end 119 of the shank 121 of the sleeve 114. The end cap 115 is generally tubular in shape and closed. at distal end 126, except for opening 120. The reduced diameter of end cap 115 causes end cap 115 to seal around distal end 118 of cannula 112. Sleeve 114 forms a coaxial gap 130 around cannula 112. Gap 130 allows irrigation flow down gap 130 and out of openings 132. When vacuum is applied to inner lumen 136 of cannula 112, it can be aspirated material through aperture 120, down inner lumen 136 and out of tip 110.

Although certain embodiments of the present invention have been described above, these descriptions are provided for illustrative and explanatory purposes. Variations, changes, modifications and deviations from the systems disclosed above may be adopted without departing from the scope of the present invention.