Posterior chamber intraocular lens insertion during pars plana lensectomy and vitrectomy for complications of proliferative diabetic retinopathy.

We inserted posterior chamber lenses into 21 eyes with complications of diabetic retinopathy upon completion of pars plana lensectomy and vitrectomy in a single session. After the original surgery, two eyes developed retinal detachments and underwent vitrectomy revisions with scleral buckling, one eye had a fluid-gas exchange for residual vitreous cavity blood, one eye had supplemental laser treatment, and one eye had intraocular antibiotics for endophthalmitis. Six months later, postoperative vision was better in 16 of the 21 eyes (76%), the same in four eyes (19%), and worse in one eye (5%). In 16 eyes visual acuity was 20/200 or better, and in six eyes it was 20/40 or better postoperatively. Decreased vision was caused by preexisting macular disease; two eyes had corneal edema with iris neovascularization associated with residual retinal detachment. The procedure and lenses were well tolerated and provided good pseudophakic vision.

Silicone intraocular lens implants and circular anterior capsulotomy (capsulorhexis).

Anterior circular capsulorhexis is used to guarantee accurate placement and stability for the flexible silicone intraocular lens. The smaller wound needed for this procedure allows for immediate postoperative bending by the patient. The visual results achieved with this implant are excellent.

[Methods of capsular and intracapsular microsurgery, intracapsular implantation and sutureless fixation of artificial lenses]. / O metodike kapsul'noi i interkapsul'noi mikrokhirurgii, mezhkapsul'noi implantatsii i besshovnoi fiksatsii iskusstvennogo khrustalika.

The author recommends mastering the methods of capsular and intracapsular microsurgery for cataracts on cadaver eyes. He advises to remove the cornea and the iris to have a better view of the technique. As the physician masters the technique, he screens the lens sac equatorial area by keeping the iris and later the cornea (to make the conditions as close to clinical surgery as possible) and then removes the iris and the cornea for controlling the quality of the capsular pocket preparation. Artificial lenses similar in shape to B. N. Alexeev's design may be implanted in the prepared lens sac; then the anterior capsule of the lower capsular pocket in the central area is removed. The training may be completed by removal of the anterior capsule alone, i.e. by extracapsular extraction. The described methodology helps more rapidly master the techniques of capsular and intracapsular microsurgery and intracapsular implantation of artificial lenses and thus promotes a wide practical employment of these microsurgical techniques.

Posterior chamber intraocular lens implantation during pars plana lensectomy and vitrectomy for diabetic complications.

Ten eyes had posterior chamber lenses implanted in the ciliary sulcus in front of the anterior lens capsule during diabetic pars plana lensectomy and vitrectomy. Six months later, nine eyes had improved vision and one had the same vision as compared with preoperative acuity levels. Two eyes had 0.5 and eight eyes had 0.1 or better acuity. None of the eyes developed iris or angle neovascularization or glaucoma, and all ten eyes had clear vitreous cavities with attached maculas. The posterior chamber lenses were well tolerated and provided good visual rehabilitation.

Keratorefractive aspects of the scleral pocket incision and closure method for cataract surgery.

All current cataract incisions induce transient and permanent changes in corneal astigmatism. Typically, a two-phase astigmatic response is observed; an initial with-the-rule change is followed by an eventual and permanent against-the-rule shift from preoperative astigmatism. The earlier literature suggests that the magnitude of the net astigmatic swing approximates 6.0 diopters for large limbal wounds closed with interrupted sutures. However, applying the tenets of keratorefractive surgery to the cataract incision and its closure allows the surgeon to limit postoperative iatrogenic astigmatic swings. The reduced phacoemulsification incision size in combination with a scleral pocket closed with a continuous single knotted 10-0 monofilament nylon suture under tonometric and keratometric control significantly dampens the changes in corneal astigmatism during the early and late postoperative periods. My published reports, as evaluated in the present study, reveal that the net astigmatic swing may be reduced to less than 1.5 diopters, thereby affording rapid and stable optical results.

La catarata y el lente intraocular / The cataract and the intraocular lens

Se revisan los resultados del implante de 405 lentes Intra-Oculares en camara posterior en la FUNDACION OFTALMOLOGICA DE SANTANDER, durante el periodo comprendido entre el 25 de enero de 1985 y el 5 de julio de 1986; se encuentran resultados en agudeza visual post-operatoria mejores a 20/30 en el 83.4% y 20/50 en 8.3% de los pacientes. Se observa un numero menor de complicaciones a las esperadas con otras tecnicas operatorias antiguas. Se comprueba una disminucion en las cifras tonomeicas en el post-operatorio. Se presentan las conclusiones y recomendaciones sobre los resultados obtenidos. La tecnica para el tratamiento de la catarata con extraccion e implante de lente en camara posterior, demuestra su bondad en terminos de funcionalidad visual y confort para el paciente

Posterior capsular opacification and intraocular lens decentration. Part II: Experimental findings on a prototype circular intraocular lens design.

In a prospective randomized study, 25 New Zealand white rabbit eyes were implanted with four intraocular lens (IOL) designs. These included a one-piece modified J-loop IOL, a three-piece modified J-loop IOL, a rigid disc IOL, and an experimental compressible disc (CD) IOL. The CD IOL revealed the lowest mean posterior capsular opacification (PCO) of all IOLs tested (P less than .01). With all lenses tested, a positive correlation between PCO and decentration was found (R = 0.55, P less than .05). These results suggest that because of its design features (i.e., one-piece construction, biconvex optic, posterior angulation of the fixation element), the CD lens produces a mechanical barrier against lens epithelial cell migration and reduces the incidence of PCO.

Intraocular lens implantation: a model for the Third World.

Intracapsular cataract extraction has long been thought of as the appropriate technique to deal with the backlog of Third World cataract blindness. However, this operation may not be as sight effective as many believe. The authors offer their experience of intraocular lens implantation in the Torres Strait as a model for a more visually appropriate surgical cure for Third World cataract.

Comparison of Healon and Viscoat in cataract extraction and intraocular lens implantation.

Sixty patients were randomly assigned to Healon (20 patients) or Viscoat (40 patients) treatment during extracapsular cataract extraction and intraocular lens implantation surgery. The 40 patients in the Viscoat group were randomly subdivided into two groups. In one group (20 patients), Viscoat was irrigated/aspirated from the eye at the close of surgery, while in the second group of 20 patients, Viscoat was left in the eye. In all Healon cases, the viscoelastic substance was removed from the eye at the end of the surgical procedure. Compared with Viscoat, Healon better facilitated the surgical procedure and appeared to be a more advantageous viscoelastic preparation. Viscoat, in many cases, caused rises in intraocular pressure in the immediate postoperative period when either removed or left in the eye at the close of surgery.

Measurement of intraocular lens decentration and tilt in vivo.

A method for measuring the tilt and decentration of intraocular lenses (IOLs) in the static eye using the Purkinje image locations is presented. The patient fixates on a target that is coaxial with the camera or is at a predetermined angle with the camera axis. A telecentric stop is introduced in the camera so the positions of the Purkinje images on the film are independent of their distance from the camera. Measurements of the image locations on the film are used with anterior chamber depth and corneal curvature measurement to calculate the tilt and decentration of the IOL. In a group of 14 randomly selected patients with posterior chamber IOLs, 13 gave Purkinje images that could be measured. The average tilt was 7.8 degrees and the average decentration was 0.7 mm.

Lentes intraoculares en el Hospital Central Urquinaona de Maracaibo: años 1984-87 / Intraocular lenses in the Hospital Central Urquinaona, Maracaibo: years 1984-87

En este trabajo se hizo la revisión de 200 cirugías de cataratas con implante de LIOS realizados en el H.C.U. de Maracaibo, desde mayo del 84 hasta julio del 87. Se estudiaron varios parámetros, como edad, sexo, patología general, patología ocular asociada, tipo de lente, av pre-operatoria y post-operatoria