Small incision intraocular lens: past, present and future.

Research indicates that silicone is comparable to or exceeds PMMA as an intraocular lens material. Insertion of silicone lenses does, however, continue to be a source of discussion and studies continue to develop more affective insertion instrumentation. Hydrogel also appears to be a viable material for intraocular lenses. Because hydrogel can be dehydrated and inserted flat in the eye with forceps, there is no problem with insertion instrumentation. Studies with these lens materials is preliminary and ongoing. Future work will include work with acrylics, endocapsular surgery (liquid gels, injectable and inflatable lenses), a teledioptric lens for macular degeneration, and an intraocular biofocal. The future also holds further silicone and hydrogel studies and the possible development of other materials for intraocular lenses all in search of the optimum intraocular lens material and design.

Clinicopathologic observations of a silicone posterior chamber lens in a primate model.

A primate model was used to compare a silicone intraocular lens (Elastic Lens, STAAR Surgical) and a conventional polymethylmethacrylate/polypropylene lens. Tolerance and stability of silicone lenses within the eye were tested.

Flurbiprofen 0.03% for the control of inflammation following cataract extraction by phacoemulsification.

We conducted a double-masked, vehicle-controlled study to evaluate the anti-inflammatory effect of topical flurbiprofen in cataract surgery by phacoemulsification and implantation of a posterior chamber intraocular lens. The 233 patients were randomized to receive either flurbiprofen or vehicle immediately prior to and for two weeks following surgery. No concomitant corticosteroid use was allowed. The flurbiprofen group had significantly less anterior chamber cells and flare at day 7 and significantly less conjunctival erythema, corneal edema, and lid edema at day 14. The investigator's global effectiveness rating was higher in the flurbiprofen group at day 14. Blood-aqueous barrier disruption, as measured by aqueous fluorophotometry, was statistically significantly diminished in the flurbiprofen group. Burning and stinging were rated significantly greater in the flurbiprofen group than in the vehicle group. Foreign-body sensation and photophobia were significantly more severe in the vehicle group than in the flurbiprofen group. Flurbiprofen provided postsurgical anti-inflammatory efficacy in clinical signs of inflammation and in blood-aqueous barrier disruption, and also showed improved subjective signs.

Initial experience with the HydroSonics instrument to soften cataracts before phacoemulsification.

An ultrasonically driven needle placed into the body of the nucleus, with subsequent injection of balanced salt solution (BSS), can be used to fragment the nucleus into sections or lamellae that can potentially be emulsified with greater ease and less ultrasound energy delivered to the eye. This separation of the nucleus has been designated hydrodelineation. The six surgeons participating in this study subjectively reported that the use of hydrodelineation facilitated phacoemulsification, on average, in 91% of their cases. Review of study data indicated that significantly less ultrasound time and cumulative displayed energy were noted in phacoemulsification of grade 2+ and 3+ cataracts after hydrodelineation than in cases in which hydrodelineation was not performed. The results in cases performed with and without hydrodelineation were statistically equivalent in complications and postoperative patient outcomes.

Cataract wound closure with polyglactin 910 following insertion of a 4-loop Binkhorst lens: preliminary report.

In this preliminary report our results with 8-0 braided polyglactin 910 suture for cataract wound closure after insertion of a 4-loop Binkhorst lens were encouraging. However, more experience is required before valid conclusions can be reached regarding its safety. Early experience indicates that the surgeon should approach the use of 9-0 monofilament polyglactin 910 suture for cataract wound closure following insertion of an intraocular lens with extreme caution.

An evaluation of 8-0 polyglycolic acid braided synthetic absorbable suture in cataract surgery.

This study describes the operative and postoperative performance of 8-0 polyglycolic acid braided suture, trademarked Dexon "s", in cataract surgery. The evaluation consists of a clinical comparison of 8-0 Dexon to the same suture in 7-0 size in 109 cataract surgical procedures. The 8-0 Dexon, like 7-0, gave high tensile strength, good knot security, batch-to-batch uniformity, relatively good pliability, and provoked minimal reaction while disappearing at a predictable rate of around 35 days. When compared to 7-0 Dexon, 8-0 produced less tissue drag, fibrillation, and reaction, while providing better pliability. However, the smaller suture possessed less tensile strength, and had an increased tendency to cut through tissue when tied too tightly.

An evaluation of 8-0 Polyglactin 910 synthetic absorbable suture in cataract surgery.

This study describes the operative and postoperative performance of 8-0 Polyglactin 910 in cataract surgery. The evaluation represents a clinical comparison of 7-0 Polyglactin 910 to the same suture in 8-0 size in 155 cataract surgical procedures. In 45 cases, 8-0 Polyglactin 910 was the sole wound closure material used. 8-0 Polyglactin 910 provided high tensile strength, good knot security, batch-to-batch uniformity, ease of handling, minimal reaction, and a predictable absorption rate that was virtually completed in 33 days. When compared to 7-0 Polyglactin 910, 8-0 produced less tissue drag, fibrillation, and reaction. Early in our series, three cases of wound dehiscence occurred. One was caused by trauma and the other two by 8-0 Polyglactin 910 cutting through tissue. This study's conclusion stresses avoiding the tendency of tying the knot too tightly to prevent suture pull-out.

The evaluation of 7-0 Polyglactin 910 suture in cataract surgery.

The new synthetic absorbable suture, Polyglactin 910, represents a significant step toward absorbable suture perfection. In 218 cataract surgical procedures, the performance of Polyglactin 910 was compared to that of Chromic Catgut and Chromic Collagen. The results obtained in this series of cases is the basis for this article. When compared to Chromic Catgut and Chromic Collagen, Polyglactin 910 consistently provided greater tensile strength, improved handling, significantly decreased tissue reaction, more batch-to-batch uniformity, superior wound tensile strength retention, and a predictable absorption rate that is virtually completed in 35 days. Both nonprotein and nonantigenic, Polyglactin 910 evoked less tissue reaction and proved more versatile and reliable than either of the other sutures.

The use of Polyglactin 910 in muscle surgery.

This study represents the clinical evaluation of a newly developed snythetic absorbable suture, Polyglactin 910, in 5-0 and 6-0 sizes as used in muscle surgery. In 240 cases, Polyglactin 910 has spoken very well for itself. It possesses extremely high tensile strength and wound tensile strength retention, excellent handling characteristics and a predictable absorption rate, while the amount of tissue reaction it produces is consistently less than that of comparably sized sutures of Chromic Catgut. Polyglactin 910 is both versatile and reliable, and reflects important progress toward the development of "the perfect" absorbable suture. This article details Polyglactin 910's shortcomings as well as its strong points, and provides a recommended handling technique for its use.

Epikeratophakia: existing limitations and future modifications.

The predictability of optical correction has been a problem for all forms of refractive corneal surgery in epikeratophakia, changes in graft dimensions and surgical technique improved accuracy, but several problems still exist in cryolathing preserved corneal tissue. Preserved corneal tissue is quite oedematous and when frozen on the cryolathe, assumes an irregular shape. A mechanical technique to dehydrate tissue was developed which yields corneal tissue which behaves in a predictable fashion. The use of donor corneal tissue in refractive surgery has certain inherent limitations. There is no way of measuring the power of the lathed corneal lens prior to surgery; the power is a function of the shape the lens will take in vivo. The ability to supply large numbers of donor corneal buttons may be an impractical task should this type of surgery become widely used. The use of alloplastic lenses should overcome most of these difficulties.

Comparative evaluation of coated and uncoated polyglactin 910 in cataract and muscle surgery.

This study describes the intraoperative and postoperative performance of coated and uncoated Polyglactin 910 in cataract and muscle surgery. The evaluation represents an animal and clinical comparison of 5-0 coated and uncoated Polyglactin 910 in 50 muscle cases and 7-0 coated and uncoated Polyglactin 910 in 150 cataract cases. Both Polyglactin 910 sutures provided high tensile strength, good knot security, batch-to-batch uniformity, ease of handling, minimal reaction, and a predictable absorption rate. Improvements noted in the coated suture were: (1) easier passage through tissue, (2) less chatter in tying, (3) fewer instances of premature tie, and (4) decreased tendency to incarcerate tissue.

A comparative evaluation of 9-0 monofilament and 9-0 braid polyglactin 910 in cataract surgery (intracapsular, extracapsular, and phacoemulsification).

This study describes the operative and postoperative performance of 9-0 monofilament and 9-0 braid Polyglactin 910 synthetic absorbable sutures in cataract surgery. The evaluation represents a clinical comparison of the sutures in 150 cataract surgical procedures. In a comparative evaluation each suture provided specific performance advantages: (table: see text). To date, the 9-0 monofilament and 9-0 braid Polyglactin 910 sutures are the smallest useful absorbable sutures developed for cataract surgery. While these sutures seem safe for use with phacoemulsification as sole wound closure materials, we recommend the use of nylon stints for intracapsular and extracapsular procedures until further experience is gained.

9-O monofilament polydioxanone (PDS): a new synthetic absorbable suture for cataract wound closure.

This study describes the intraoperative and postoperative performance of 9-O monofilament Polydioxanone (PDS) suture for cataract wound closure. This newly developed synthetic absorbable suture is designed to meet the need for a "long-term" absorbable suture material suitable for cataract wound closure following intraocular lens implantation. Polydioxanone's advantages over currently used "short-term" absorbables and biodegradable nylon are described in this report.

The biologic and physical criteria for suture selection in cataract surgery.

This paper has disucssed histochemical, physical, and clinical considerations involved in proper suture selection for cataract surgery. Guidelines are proposed so that the surgeon can employ a standard method for evaluating each suture's performance. Accordingly, the surgeon can select the proper proper suture to satisfy his needs regardless of his operative technique.

New techniques of viscosurgery with phacoemulsification.

Sodium hyaluronate is a valuable aid for phacoemulsification and intraocular lens insertion. Procedures such as anterior capsulotomy, polishing the capsule, lens adjustment, incision closure, and conversion to planned extracapsular cataract extraction are facilitated when sodium hyaluronate is used. A new method of removing it from the eye is presented.

Refractive corneal surgery: the use of implantable alloplastic lens material.

A basic problem encountered in all forms of lamellar refractive surgery has been the predictability of the optical corrections. Corneal tissue used in refractive surgery behaves in a variable fashion because its shape is determined in vivo by the process of healing and graft repopulation. Therefore no preoperative measure of the ultimate power of the lathed corneal lens can be made. Another drawback is the limited supply of donor corneal tissue. In an effort to overcome these problems, we have used alloplastic materials in conjunction with lamellar refractive surgery to improve the predictability of the result. The use of this material would also allow accurate preoperative determination of lens power. Intralamellar implants appeared to heal quite rapidly after surgery. Their optical clarity was excellent and the corneal surface appeared stable. Further research into long-term stability and predictability are currently underway.