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Purpose: To evaluate the effect on donor rim cultures and postoperative infections of doubling the povidone-iodine exposure time during corneal tissue recovery before its use in keratoplasty., Methods: Consecutive donor cornea recoveries were evaluated for positive donor corneal rim cultures and postoperative infections before and after a protocol change of doubling the exposure time of povidone-iodine during donor preparation., Results: In 631 consecutive cornea donor recoveries, 18 (2.9%) had positive fungal rim cultures and 41 (6.5%) had positive bacterial rim cultures. Three (0.48%) developed postoperative fungal infections, and no bacterial infections occurred. After doubling the povidone-iodine exposure time during the recovery process, 725 consecutive corneas were reviewed. Four (0.6%) had positive fungal rim cultures, and 29 (4.0%) had positive bacterial rim cultures. No postoperative fungal or bacterial infections occurred. No noticeable increase in epithelial toxicity developed between the 2 groups., Conclusions: Increasing the povidone-iodine exposure time during the donor cornea recovery process decreased the rate of positive donor corneal rim fungal cultures (P = 0.001), positive donor corneal rim bacterial cultures (P = 0.04), and postoperative fungal infections (P = 0.06).

Objective: To determine whether endothelial cell loss 5 years after successful corneal transplantation is related to the age of the donor., Design: Multicenter, prospective, double-masked clinical trial., Participants: Three hundred forty-seven subjects participating in the Cornea Donor Study who had not experienced graft failure 5 years after corneal transplantation for a moderate-risk condition (principally Fuchs' dystrophy or pseudophakic corneal edema)., Testing: Specular microscopic images of donor corneas obtained before surgery and postoperatively at 6 months, 12 months, and then annually through 5 years were submitted to a central reading center to measure endothelial cell density (ECD)., Main Outcome Measure: Endothelial cell density at 5 years., Results: At 5 years, there was a substantial decrease in ECD from baseline for all donor ages. Subjects who received a cornea from a donor 12 to 65 years old experienced a median cell loss of 69% in the study eye, resulting in a 5-year median ECD of 824 cells/mm(2) (interquartile range, 613-1342), whereas subjects who received a cornea from a donor 66 to 75 years old experienced a cell loss of 75%, resulting in a median 5-year ECD of 654 cells/mm(2) (interquartile range, 538-986) (P [adjusted for baseline ECD] = 0.04). Statistically, there was a weak negative association between ECD and donor age analyzed as a continuous variable (r [adjusted for baseline ECD] = -0.19; 95% confidence interval, -0.29 to -0.08)., Conclusions: Endothelial cell loss is substantial in the 5 years after corneal transplantation. There is a slight association between cell loss and donor age. This finding emphasizes the importance of longer-term follow-up of this cohort to determine if this relationship affects graft survival.

Objective: To determine whether graft survival over a 5-year follow-up period using corneal tissue from donors older than 65 is similar to graft survival using corneas from younger donors., Design: Multicenter prospective, double-masked, controlled clinical trial., Participants: One thousand ninety subjects undergoing corneal transplantation for a moderate-risk condition (principally Fuchs' dystrophy or pseudophakic corneal edema); 11 subjects with ineligible diagnoses were not included., Methods: Forty-three participating eye banks provided corneas from donors in the age range of 12 to 75 with endothelial cell densities of 2300 to 3300 cells/mm(2), using a random approach without respect to recipient factors. The 105 participating surgeons at 80 sites were masked to information about the donor cornea including donor age. Surgery and postoperative care were performed according to the surgeons' usual routines. Subjects were observed for 5 years., Main Outcome Measures: Graft failure, defined as a regraft or a cloudy cornea that was sufficiently opaque as to compromise vision for a minimum of 3 consecutive months., Results: The 5-year cumulative probability of graft survival was 86% in both the <66.0 donor age group and the >/=66.0 donor age group (difference = 0%, upper limit of 1-sided 95% confidence interval = 4%). In a statistical model with donor age as a continuous variable, there was no significant relationship between donor age and outcome (P = 0.11). Three graft failures were due to primary donor failure, 8 to uncorrectable refractive error, 48 to graft rejection, 46 to endothelial decompensation (23 of which had a prior, resolved episode of probable or definite graft rejection), and 30 to other causes. Distributions of the causes of graft failure did not differ between donor age groups., Conclusions: Five-year graft survivals for cornea transplants at moderate risk for failure are similar using corneas from donors >/= 66.0 years and donors < 66.0. Surgeons and patients now have evidence that corneas comparable in quality to those used in this study from donors through age 75 are suitable for transplantation.

Objective: To study the safety and efficacy of simultaneous bilateral laser in situ keratomileusis (LASIK)., Design: Prospective randomized clinical trial., Participants: Fourteen surgeons and 714 consecutive eyes of 357 patients who desired surgical correction of myopia ranging from -2.00 to -22.50 diopters., Intervention: Patients were randomized to simultaneous or sequential bilateral LASIK., Main Outcome Measures: Primary outcome measures were safety and efficacy. Procedure safety was assessed, for simultaneous and sequential groups, by comparison of intraoperative and postoperative complication rates and the percentage of eyes losing two or more lines of spectacle-corrected visual acuity. Procedure efficacy was assessed by comparison of the percentage of eyes with uncorrected visual acuity better than or equal to 20/20 and 20/40 and the percentage of eyes within +/-0.50 and +/-1.00 diopters of intended outcome., Results: Three hundred seventy-eight eyes were enrolled in the simultaneous group, and 331 eyes were enrolled in the sequential group. Mean follow-up was 10 months (+/-4.2 months standard deviation; range, 2 weeks-22 months). There was no significant difference in intraoperative complication rate (P = 0.55), loss of two or more lines of spectacle-corrected visual acuity (P = 0.87), or percentage of eyes within +/-0.50 diopters of intended correction (P = 0.17) between simultaneous and sequential groups. Postoperative complications were not significantly different in the two groups except for the unexplained more frequent epithelial ingrowth in the simultaneous group (2.9%) than in the sequential group (0.6%). The adjusted odds ratio for epithelial ingrowth in the simultaneous group was 1.02 (95% confidence interval, 1.01-1.08). There was no increased likelihood of epithelial ingrowth in the second of two simultaneously treated eyes (P = 0.95)., Conclusion: The outcomes and complications of performing bilateral simultaneous LASIK were not significantly different from those of sequential treatments, with the unexplained exception of more frequent epithelial ingrowth in the simultaneous group.

Objective: This study aimed to determine whether there is a true difference in predictability between single-zone and multizone laser in situ keratomileusis (LASIK) for the correction of low myopia or whether any difference in predictability is because of a need for separate clinical nomograms for the two treatments., Design: A prospective, randomized, clinical trial., Participants: Fourteen surgeons and 190 eyes of 95 patients with myopia who desired surgical correction of myopia ranging from -2.00 to -7.00 diopters (D) participated., Intervention: Fellow eyes of patients with myopia undergoing bilateral simultaneous LASIK were randomized to single-zone and multizone ablation. Astigmatism was not corrected at the time of LASIK., Main Outcome Measures: Predictability, postoperative videokeratography, and contrast sensitivity were assessed at 3 months after surgery., Results: At 3 months, r2 values relating laser setting to change in spherical equivalent refraction were 0.78 for single-zone and 0.76 for multizone ablation; mean outcome with respect to intended was -0.84 D (0.65 standard deviation [SD]) for single-zone and -0.62 D (0.78 SD) for multizone eyes (P = 0.035). There was no relationship between single-zone and multizone ablation and the likelihood of asymmetric postoperative videokeratography (P = 0.83). The only difference in contrast sensitivity was a significantly greater decrease in log contrast for multizone eyes at 12 cyc/deg under undilated conditions., Conclusions: There is no true difference in predictability between single-zone and multizone LASIK for the correction of low myopia. Separate clinical nomograms for single-zone and multizone LASIK should eliminate the difference in predictability that was observed in this clinical trial.

Purpose: To assess the effects of laser in situ keratomileusis (LASIK) on the corneal endothelium., Methods: In a prospective study, the corneal endothelium of 98 eyes of 65 consecutive patients (mean age, 41 years; range, 22 to 66 years) was photographed before, 2 weeks after, and 12 weeks after LASIK for the correction of 2.75 to 14.5 diopters of myopia. Theoretical ablation depths were 200 to 330 microm below the corneal surface. Cell density, coefficient of variation, and percent of hexagonal cells were determined using 150 to 200 cells from each image. Eighty-eight eyes (91%) of 59 patients had a history of contact lens wear., Results: The mean+/-SD preoperative endothelial cell density was 2,549+/-365 cells per mm2, and the mean coefficient of variation was 0.35+/-0.06. There was no statistically significant change in the mean endothelial cell density or mean coefficient of variation of cell size at the 2-week (2,561+/-360 cells per mm2 and 0.35+/-0.06) or 12-week (2,541+/-364 cells per mm2 and 0.35+/-0.05) postoperative examinations. The percent of hexagonal cells was not significantly changed 2 weeks postoperatively; however, 12 weeks postoperatively (P=.0413, two-tailed t test), the percent of hexagonal cells was decreased by 1%., Conclusions: Corneal endothelial cell density and morphology were unchanged 2 and 12 weeks after LASIK for the correction of up to 14.5 diopters of myopia. In this LASIK study, the correction of up to 14.5 diopters of myopia appears to cause no clinically significant effect on corneal endothelial cell density or morphology.

Purpose: To study the safety and efficacy of simultaneous bilateral laser in-situ keratomileusis (LASIK) METHODS: Data were obtained from 254 consecutive patients that were randomized to simultaneous or sequential bilateral LASIK., Results: 146 patients were enrolled in the simultaneous group and 108 patients were enrolled in the sequential group. Mean follow-up was 10 months (range 6-18). There was no significant difference in intraoperative complication rate (p = 0.34), loss of two or more lines of spectacle corrected visual acuity (p = 0.9), or percentage of eyes within +/- 0.50 D of intended (p = 0.63) between simultaneous and sequential groups., Conclusions: The risk of performing bilateral simultaneous LASIK is not significantly different from that of sequential treatments.

Purpose: To evaluate comprehensively the magnitude of suspected risk factors for corneal graft failure from any cause, failure from rejection, and immunologic reaction in patients at high risk for graft failure after corneal transplantation., Methods: The records of the 457 participants in the Collaborative Corneal Transplantation Studies were reviewed. All participants had at least two quadrants of stromal vascularization and/or a history or previous graft rejection. Patients were followed for 2 to 5 years. Characteristics of the patient, study eye, donor, donor-recipient histocompatibility, and surgical procedure were examined for their association with the graft outcomes of failure from any cause, rejection failure, and immunologic reaction. Multivariate survival analysis techniques were used to estimate rates of graft outcome events and to estimate the magnitude of risk factors., Results: Many apparent risk factors did not maintain their association with graft outcomes after adjustment for other risk factors. Young recipient age, the number of previous grafts, history of previous anterior segment surgery, preoperative glaucoma, quadrants of anterior synechiae, quadrants of stromal vessels, a primary diagnosis of chemical burn, and blood group ABO incompatibility were among the strongest risk factors identified for graft failure. Donor and corneal preservation characteristics had little influence on graft outcome., Conclusions: Risk of graft failure varies substantially, even within a high-risk population. The number of risk factors present should be considered by the patient and surgeon when contemplating transplantation and planning follow-up.

Three hundred fourteen members of the Castroviejo Society were surveyed to determine current practices in the prevention and treatment of corneal graft rejection. One hundred thirty-seven responses were received and tabulated for routine postoperative prophylactic immunosuppression as well as treatment of epithelial rejection, endothelial rejection (three patterns), subepithelial infiltrates, acutely and progressively opacifying grafts without inflammation, and photophobia. All respondents applied topical steroids in the postoperative period, while about half also administered steroids subconjunctivally. For the treatment of obvious endothelial rejection, 100% of respondents used topical steroids, 57% used subconjunctival steroids, and 37% used systemic steroids. Prednisolone acetate, 1%, was the preferred topical preparation for all conditions (55-68% of respondents). Individual responses to the questionnaire showed a surprisingly wide variation in treatment preferences.

Presented are the results of 66 consecutive, elective, combined procedures of penetrating keratoplasty, extracapsular cataract extraction, and intraocular lens insertion (triple procedure) performed by three surgeons between January 1981 and January 1984. After a mean postoperative followup of 15.8 months, over 90% of the eyes had clear grafts, and of the 56 eyes with good preoperative visual potential, 77% achieved a best corrected visual acuity of 20/40 or better. The postoperative mean refractive deviation from emmetropia was 2.17 diopters, with a range of +6.62 D to -5.50 D, 62% falling between -2.00 and +2.00 diopters. Using multiple regression analysis of preoperative and postoperative variables, an attempt was made to derive a predictive formula for the power of the intraocular lens to be implanted during the triple procedure. In contrast to cataract surgery, where axial length and corneal power remain fairly constant preoperatively and postoperatively, penetrating keratoplasty produces marked changes in corneal curvature and power. Therefore, a single formula could not be derived to predict accurately the intraocular lens power for the patients. However, using the results for an individual surgeon, a formula was derived that could improve the predictability of intraocular lens power.

The clinical results of penetrating keratoplasty for iridocorneal endothelial (ICE) syndrome are presented. Nine cases of penetrating keratoplasty for ICE syndrome were reviewed retrospectively. All grafts remain clear, with posterior corneal changes occurring in only one case, after a mean follow-up of 43 months. Penetrating keratoplasty produced visual improvement in 7 of the 9 cases, relief of pain in 6 of 6 cases, and prevention of further corneal infection in 1 case. We believe that penetrating keratoplasty has a place in the treatment regimen of this disease, not only to achieve improvement in vision, but also for relief of pain, and avoidance of recurrent corneal infections, and to allow a clear media for careful monitoring of optic disc and field changes in the associated glaucoma.

Eighty-five patients undergoing penetrating keratoplasty with tissue from donors supported by mechanical ventilation (Ventilator group) were compared to a surgeon- and diagnosis-matched group (Control group). Age at surgery, duration of follow-up, and sex of recipient patients were similar in the two groups. The mean donor age in the Ventilator group (26.4 years) was significantly less than in the Control group (45.8 years, P less than 0.0001). Mean time on the ventilator was 99.4 hours (range, 4 hours to 21 days). Overall graft survival rates in the Ventilator and Control groups were similar (P greater than or equal to 0.72). Time on the ventilator did not affect graft survival. Cultures of corneoscleral donor rims were positive more often in the Ventilator group than in Controls (39.7 versus 23.1%), but the difference was not significant (P = 0.09). Prolonged ventilator time was not associated with a higher rate of positive corneoscleral rim cultures, nor did positive cultures affect graft survival. The most common cause of graft failure in both groups was allograft rejection. In no case could postoperative bacterial infection be attributed to contamination of the donor material. One case of primary donor failure occurred in the Ventilator group, but the incidence (1.2%) is similar to that of previously reported studies. The data indicate that corneal tissue from ventilator-supported donors should be considered for use in penetrating keratoplasty.

Retrospectively studied were 91 patients, 14 years of age or less, who had 152 penetrating keratoplasties in 107 eyes, with an average follow-up of 30.1 months. Survival analysis showed the probability of obtaining a clear graft at one year to be 60 +/- 8% in 45 eyes with congenital opacities, 70 +/- 8% in 31 eyes with opacities from trauma and 73 +/- 8% in 31 eyes with acquired nontraumatic opacities. Most failures occurred during the first postoperative year and were characterized by the gradual loss of graft clarity from undetermined cause. Twenty-nine percent (10) of the 34 eyes with congenital corneal opacities in which vision could be measured had a most recent visual acuity better than 6/120 (20/400). Irreversible amblyopia, glaucoma, other structural abnormalities of the anterior segment and mental retardation complicated visual rehabilitation in the congenital group. In the post-traumatic group, vision was better than 6/120 (20/400) in 45% (13) of 29 eyes, being limited by vitreoretinal pathology, fibrous ingrowth, and optic nerve damage from glaucoma. Visual acuity in the acquired, nontraumatic group was better than 6/120 (20/400) in 67% (20) of 30 eyes. The percentage of patients achieving 6/12 (20/40) or better in the congenital, post-traumatic, and nontraumatic groups were 3% (1/34), 17% (5/29), and 47% (14/30), respectively. In the congenital group, only patients with posterior polymorphous dystrophy obtained a visual acuity of 6/30 (20/100) or better. Preoperative vascularization of the cornea, persistent epithelial defects, and performance of lensectomy-vitrectomy were factors most highly correlated with poor graft survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Two hundred thirty-two penetrating keratoplasties in 228 eyes were performed with or without the removal of donor corneal epithelium in a prospective, randomized clinical trial to determine the effect of epithelial removal on graft survival. The removal of epithelium did not reduce the likelihood of graft failure, irreversible allograft reaction, or reversible allograft reaction.

We retrospectively evaluated selective removal of interrupted nylon sutures to reduce astigmatism following penetrating keratoplasty in 68 eyes with eight or 12 interrupted sutures and one running suture. Following removal of one to four interrupted sutures at one visit (N = 234 visits), corneal astigmatism had changed 2 to 3 diopters (range 0 to 12 D) by the next visit. The astigmatism decreased greater than or equal to 1 D in 54%, changed 0 to .87 D in 28%, and increased greater than or equal to 1 D in 18%. When a total of five or six sutures were removed during the 5 months following surgery, less than 3 D of residual astigmatism was present in 50 eyes (74%). The axis of astigmatism changed less than or equal to 40 degrees in 74% (n = 65). In a second group of 20 eyes with double running sutures, removal of the 10-0 running suture in all 20 eyes produced an average change of 1.8 D (range = 0 to 3.75 D), with an equal number of increases and decreases. Vector analysis showed the total induced change in astigmatism was approximately twice the absolute keratometric change.

We used argon laser trabeculoplasty to treat medically uncontrolled glaucoma after penetrating keratoplasty in ten eyes that were aphakic or pseudophakic. These patients were examined over an average of 22.8 months (range, 12 to 37 months) after treatment. We found an average decrease in intraocular pressure of 9.1 mm Hg (range, +8 to -19), from an average of 30.6 mm Hg before treatment to an average of 21.5 mm Hg after treatment. Eight of ten eyes had a reduction of greater than 5 mm Hg, and six of ten eyes had intraocular pressure of less than 20 mm Hg. Visual function remained stable, and complications were rare. We now prefer argon laser trabeculoplasty to cyclocryotherapy for the initial treatment of patients with medically uncontrolled glaucoma who have predominantly open angles and a clear penetrating keratoplasty.

We reviewed the records of 26 consecutive patients undergoing penetrating keratoplasty for pseudophakic corneal edema in which the original intraocular lens was retained. The average interval between lens implantation and penetrating keratoplasty was 31.5 months. Follow-up after keratoplasty ranged from 11 to 59 months, with an average of 24.5 months. Six patients had anterior chamber lenses; sixteen, iris or iridocapsular lenses; and four, posterior chamber lenses. A vitrectomy was performed in 14 (54%) patients. Of the 21 patients with clear grafts (80%), 8 (38%) had vision of 20/40 or better while 7 (33%) had acuities of 20/200 or worse. Visual acuity of 20/40 or better was attained by 3 of 4 (75%) patients with posterior chamber lenses but only 3 of 16 (19%) patients with iris-supported lenses. Cystoid macular edema was the principal cause of decreased acuity in 12 of the 13 patients with clear grafts and acuity less than 20/40. Angiographic confirmation was obtained in 7 of 12 patients. Overall, the results are similar to those reported for pseudophakic keratoplasty with intraocular lens removal. No adverse effect of retaining a securely fixated intraocular lens was demonstrated.

We studied one eye in each of 25 consecutive patients with pseudophakic corneal edema. Each patient underwent a penetrating keratoplasty with exchange of intraocular lenses and was followed up for 12 to 38 months (mean, 18.7 months). The corneal graft remained clear in 22 (88%) eyes, but only eight eyes (32%) had acuity of 20/40 or better; nine eyes (36%) manifested cystoid macular edema, and six eyes (24%) had degenerative maculopathy. Elevated intraocular pressure was present in 12 eyes after surgery, with three eyes manifesting visual field loss; in all eyes the condition was controlled medically. Peripheral anterior synechiae appeared postoperatively in two eyes. We now treat severe cases of pseudophakic corneal edema with a penetrating keratoplasty, meticulous anterior vitrectomy, gonioplasty, iridoplasty, and exchange of intraocular lenses, employing a flexible-loop anterior chamber lens or a posterior chamber lens sutured to the iris.

To determine the relationship between corneal allograft rejection and failure, we studied patients who underwent penetrating keratoplasty for herpes simplex keratitis (n = 82) and keratoconus (n = 345), two frequent indications for keratoplasty in young patients, using survival analysis. For first grafts for herpes, the probability of survival was significantly less than it was for keratoconus (P less than 0.0001). For second grafts, this difference was less pronounced, and for three or more grafts, the difference in survival was not significant. The incidence of rejection episodes was similar in first grafts for herpes (16.6%) and keratoconus (18.5%) (P greater than 0.05). However, the incidence of rejection episodes in regrafts for herpes was significantly greater than in keratoconus (23.7 versus 17%, P less than 0.01). The incidence of failure after rejection episodes (first grafts and regrafts combined) was significantly greater in grafts for herpes (52.4 versus 16.2%, P less than 0.001). Because survival after multiple regrafts in both groups is poor, additional measures, such as tissue matching, may be necessary to improve the likelihood of success in these high-risk cases.

The authors reviewed 108 bacterial and fungal corneal ulcers that developed 1 to 72 months after penetrating keratoplasty in 79 eyes of 78 patients. Graft hypesthesia, topical corticosteroid and antibiotic treatment, exposed sutures, epithelial defects, and poor visual acuity commonly predated infectious keratitis. There were 69 bacterial, 34 fungal, and 5 combined infections. Candida albicans and Staphylococcus epidermidis were the most common pathogens. Follow-up after infection averaged 23 months (range, 1-80 months). Despite hospitalization and fortified topical antibiotic treatment, complications such as wound dehiscence and corneal perforation necessitated emergency regraft in 38 (35%) cases. Of 73 previously clear grafts, only 29 (40%) retained clarity. Median visual acuity, 20/200 before infection, fell to counting fingers at last follow-up; 12 eyes lost light perception.