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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.

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.

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.

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.