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Thirteen patients were instructed in a technique of self-management of insulin-dependent diabetes mellitus, using multiple home-monitored blood glucose determinations and multiple injections of regular insulin in conjunction with once-daily Ultra Lente insulin. Hemoglobin A1c and quantitative fluorescein fluorophotometry were used to assess blood glucose control and retinal permeability, respectively. In those patients achieving normal blood glucose control, retinal vascular leakage was statistically identical to that of a nondiabetic control population. In those patients less well controlled, retinal permeability did not differ statistically from values observed in a population of insulin-dependent diabetic patients under “standard” control. It is concluded that with “tight” control of blood sugar and normalized A1c hemoglobin, retinal permeability similarly is normalized.

The incidence of pseudophakic bullous keratopathy, now the most common indication for penetrating keratoplasty, is increasing. Since over one million intraocular lenses were implanted in 1986, a large number of eyes are at risk. The etiology of pseudophakic bullous keratopathy is varied and depends in great part on the surgical technique used for cataract extraction. Given the magnitude and changing patterns of intraocular lens usage, a review of pseudophakic bullous keratopathy is appropriate.

Previous studies have shown that momentary contact between a methylmethacrylate intraocular lens and the corneal endothelial cells results in extensive cell damage. This contact damage is reduced by coating the pseudophake with various solutions prior to contact with the endothelium.

Our clinical study was designed to determine whether "through-and-through" corneal sutures would prevent the postoperative intraocular pressure rise that occurs in 70% of aphakic eyes after uncomplicated penetrating keratoplasty. Twenty-five aphakic patients received the same operative procedure except that the corneal buttons of ten of them were sutured into place with "through-and-through" sutures. The intraocular pressures of patients with the "through-and-through" sutures were significantly lower than those of the other patients during the entire postoperative course.

Outflow facility was measured in 6 human eye bank eyes following penetrating keratoplasty and cataract extraction. A 7.5 mm corneal button was removed and replaced by an 8 mm button using conventional mid-to-deep stromal sutures. Baseline outflow facility in the phakic eyes (0.28 +/- 0.12 microliter/min/mm Hg, mean +/- SD) was unchanged (0.29 +/- 0.12) following the cataract extraction and penetrating keratoplasty using the larger corneal button.

Two different intraocular irrigating solutions were used during pars plana vitrectomy. Use of glutathione-bicarbonate-Ringer's (GBR) solution resulted in significantly fewer corneal complications and less endothelial damage when compared to lactated Ringer's solution. The visual results were disappointing.

Quantitative vitreous fluorophotometry was used to study the alteration of the blood-retinal barrier in 116 patients with diabetes mellitus of adult onset. The patients were in good stable metabolic control on injectable insulin, oral hypoglycaemics, or diet therapy. Vitreous fluorophotometry readings were abnormally high but similar in all three groups and in those with or without early background retinopathy. A higher incidence of systemic hypertension was noted in those patients requiring oral agents compared to those on insulin or diet therapy.

Fluorophotometry was used to evaluate the integrity of the blood-ocular barriers to fluorescein in experimental diabetes mellitus in rats. This technique allowed quantitation of ocular fluorescein concentrations following intravenous injection. Streptozotacin-induced diabetes resulted in an increased fluorescein accumulation in the anterior chamber (1.52 +/- 0.17 microgram/ml, mean +/- S.E.M.) and vitreous (0.82 +/- 0.11) over baseline nondiabetic levels (0.68 +/- 0.80 and 0.40 +/- 0.03, respectively). Fluorophotometry was repeated at 5, 13, and 20 days following portal vein pancreatic islet transplantation. At 5 days anterior chamber (1.40 +/- 0.17) and vitreous (0.61 +/- 0.08) fluorescein concentrations remained elevated. However, at 13 and 20 days following islet transplantation, ocular fluorescein concentrations were identical to levels observed prior to the induction of diabetes. Intravenous glucose (0.5 gm/kg) tolerance testing was performed 5 and 13 days following transplantation. The glucose responses to the tolerance test were normal and similar at both times. However, at 5 days the insulin response was abnormal with a decreased initial peak and an absent second peak. At 13 days there was a normal biphasic insulin response. In experimental diabetes mellitus ocular vascular permeability was more closely correlated with insulin than blood glucose abnormalities.

Sequential ocular fluorophotometry was performed on 59 patients with juvenile-onset, insulin-dependent diabetes mellitus. Elevated vitreous fluorescein concentrations (greater than or equal to 6 ng per ml) occurred at study entry in 76% of the 59 patients and in 70% of the 46 diabetic patients without retinopathy. None of the 27 control subjects had a vitreous reading of this magnitude. At the conclusion of the study, 10 of the 46 patients originally without retinopathy developed Grade 1 retinopathy. In addition, 6 of the original 13 patients with retinopathy showed progression of their disease. A high (greater than or equal to 12 ng per ml) vitreous fluorescein concentration which occurred in 17 patients was associated with the presence as well as progression of diabetic retinopathy. A similar association was found for a simultaneous high vitreous and aqueous (greater than or equal to 100 ng per ml) fluorescein concentration.

Detachment of Descemet's membrane is an unusual cause of postoperative corneal edema. The typical detachment is small and usually limited to the area near the limbal wound. These peripheral detachments usually heal without sequelae as endothelium spreads over the area and secretes a new Descemet's membrane. We report an unusual case of spontaneous, extensive central separation of Descemet's membrane occurring 3 weeks following uncomplicated extracapsular cataract extraction with posterior chamber lens implant. Attempted reattachment of the membrane with intracameral air was only partially successful, but 12 weeks later the detachment spontaneously resolved with recovery of vision to 20/30. An anatomic predisposition may be implicated, because the fellow eye exhibits the diffuse thickening of Descemet's membrane. Descemet's detachment is a rare but potentially reversible cause of corneal edema following cataract surgery and should not be confused with early-onset pseudophakic bullous keratopathy.

Endothelial cell densities were measured following intracapsular cataract extraction and phacoemulsification in the same patients. Phacoemulsification caused 29 percent more endothelial cell loss than intracapsular cataract extraction (p less than .001). The degree of endothelial damage with phacoemulsification appeared to be age related and was minimal in the younger patients.

A series of 120 consecutive human penetrating keratoplasties was performed using modified McCarey-Kaufman (M-K) medium. The medium has ben altered by changing the buffer system, adding a pH indicator, and using a different antibiotic from that originally formulated. There were no cases of primary donor failure and 95 per cent clear grafts after 1 year.

Preservation of donor tissue for human keratoplasty has been evaluated using modified M-K medium. The medium has been modified by changing the antibiotic and buffer and adding a pH indicator. These changes offered theoretical and practical advantages. There were no primary donor failures in 50 consecutive penetrating keratoplasties with an overall success rate of 92 percent. Clinical specular microscopy revealed good endothelial cell survival.

Albino rabbits were used to compare the effects of filling the anterior chamber with balanced salt solution or sodium hyaluronate prior to lens expression in an extracapsular surgical technique. No significant differences were found between the two utilizing periodic slit lamp examinations, measurements of intraocular pressure, corneal thickness or corneal endothelial cell density. Sodium hyaluronate maintained a deeper anterior chamber and simplified lens expression.

Sixty-four consecutive patients with aphakic penetrating keratoplasty and penetrating keratoplasty combined with intracapsular cataract extraction were reviewed in a prospective fashion with a minimum of a one-year follow-up. Five were lost to follow-up. There were seven graft failures at the end of one year. Five of these were from 11 patients who underwent second operations because of failed grafts. Visual acuity was 20/80 or better in 29 of the patients. Pathology accounted for decreased visual acuity in all of those with visual acuity less then 20/80. Problems wre macular degeneration in 11 of the 23 patients with poor visual acuity (48%); marked cystoid macular edema in four patients (17%), advanced glaucoma in three patients (13%) and amblyopia in three patients (13%). Graft size had no significant effect on visual acuity. In terms of the final refractive error and astigmatism, there were no significant differences seen in those in whom a larger donor was used compared with those in whom a donor the same size as the recipient opening was used. Aphakic penetrating keratoplasty has shown outstanding technical success with poor visual acuity representing a difficulty in screening for non-corneal pathology. With an otherwise normal eye, the chances for excellent optical success are very good at the present time with modern techniques in aphakic penetrating keratoplasty.