William E. Whitson

Trends in the indications for penetrating keratoplasty in the midwestern United States.

Purpose. To examine the leading indications and identify the changing trends for penetrating keratoplasty (PKP) in the midwestern United States. Methods. The indications for PKPs at a single center tertiary care referral practice were tabulated to assess trends from 1982 to 1996. The data analysis was prospective after 1985. Age, gender, clinical indication for PKP, date of surgery, status of the lens at the time of surgery (phakic, aphakic, pseudophakic, cataract), and any secondary diagnoses were recorded. In pseudophakic eyes, the type of intraocular lens (IOL) present at the time of surgery was noted. Correlation analysis and linear regression were used in the SAS system, version 6.12, to test for the statistical significance in increasing or decreasing trends over the span of the study. Results. A total of 4,217 PKPs were performed on 3,263 patients. The leading indication for PKP was pseudophakic bullous keratopathy (31.5%), with 73% of these cases associated with an anterior chamber IOL, 21% associated with a posterior chamber IOL, and 6% associated with an iris-fixated IOL. Fuchs dystrophy (23.2%), keratoconus (11.4%), corneal scarring (11.2%), failed graft (8.9%), and aphakic bullous keratopathy (7.5%) followed pseudophakic bullous keratopathy in frequency. These six groups accounted for approximately 93% of all cases performed. There were significant increasing trends in the incidence of failed grafts (p = 0.0001) and corneal scarring (p = 0.0001), and decreasing trends in the incidence of aphakic bullous keratopathy (p = 0.0001). There was a significant decreasing trend in pseudophakic bullous keratopathy from 1989 to 1996 (p = 0.0031). Conclusions. Pseudophakic bullous keratopathy was the leading indication for PKP in our series. This is in agreement with the data reported in other similar studies done in North America. However, unlike most of these studies, our second leading indication was Fuchs dystrophy. This contrast may be secondary to different genetic demographics in the midwestern United States.

Suprachoroidal hemorrhage in penetrating keratoplasty

Nine cases of intraoperative expulsive suprachoroidal hemorrhage occurred in a series of 2011 consecutive penetrating keratoplasties (an incidence of 0.45%). In four cases, the complication was directly related to the anesthesia technique. The incidence of hemorrhage was 1.0% in the eyes with preoperative anterior chamber intraocular lenses (IOLs), an incidence significantly higher than for any other associated condition (P < .02). Four of the nine patients recovered a postoperative visual acuity of 20/70 or better. We discuss reasons for the relatively high incidence of hemorrhage during penetrating keratoplasty; its occurrence in relation to the type of anesthesia used, prior intraocular surgery, types of surgery performed together with the penetrating keratoplasty, and the presence of an anterior chamber IOL; and the risks introduced by hemorrhage in a fellow eye and by a previous hemorrhage in the same eye.

Orbital Osteoma in Gardner's Syndrome

A 30-year-old woman developed proptosis secondary to a left ethmoidal compact osteoma. At age 29 years, a mandibular eburnated (ivory) osteoma was excised. At age 25 years, multiple adenomatous polyps of the colon were resected. Her father, age 61 years, had multiple intestinal polyps and bilateral mandibular osteoma. A 24-year-old sister had an osteoma of the forehead. Gardners syndrome is an autosomal dominantly inherited disorder characterized by intestinal polyposis, various skin and soft tissue tumors, and osteomas of the bony skeleton. Orbital osteomas occur rarely.

Corneal Tissue Levels of Topically Applied Ciprofloxacin

The effectiveness of the fluoroquinolone ciprofloxacin is dependent on stromal drug concentrations which exceed the minimum inhibitory concentration90 (MIC90). The purpose of this study is to compare corneal tissue ciprofloxacin levels in patients exposed to three ciprofloxacin dosing regimens before undergoing penetrating keratoplasty. Thirty-one patients were assigned to one of three treatment groups. Group 1 followed a ciprofloxacin dosing regimen compatible with home use [two drops of 0.3% ciprofloxacin (Ciloxan; Alcon Laboratories, Fort Worth, TX, U.S.A.) every 4 h over a 24-h period]. Groups 2 and 3 followed a more tightly controlled dosing regimen designed for a health-care setting (two drops of Ciloxan applied by a trained professional every 15 min over a 4-h period). In groups 1 and 2, corneal epithelium was left intact, whereas in group 3 corneas were abraded. Corneal tissue samples were surgically obtained. Excised buttons were frozen and Ciloxan concentration determined by high-pressure liquid chromatography. Ciloxan corneal tissue concentrations (mean ± SD) were 8.82 ± 8.24 μg/g tissue in group 1, 166.20 ± 336.94 μg/g tissue in group 2, and 938.30 ± 1,081.51 μg/g tissue in group 3. Ciloxan penetration can be improved by administering the drug in a controlled setting at 15-min intervals over a 4-h period. Individual Ciloxan concentrations exceeded the MIC90 for most key ocular pathogens despite wide variability in all experimental groups.

Corneal tissue levels of topically applied ofloxacin

Purpose: To evaluate the levels of ofloxacin (Ocuflox®) in human corneal tissue in patients exposed to various dosing regimens and application methods. Setting: Corneal Consultants of Indiana, Indianapolis, Indiana, USA. Methods: Forty patients meeting inclusion criteria were recruited from persons scheduled to have penetrating keratoplasty (PKP). Patients were placed into one of two study groups of 20 each based on dosing regimen and application method. The SAS GLM (General Linear Models) procedure was used to test for differences in mean Ocuflox tissue concentration among study groups and for interaction effects of preoperative diagnosis, trephine size, dosing regimen, and corneal integrity. Results: Corneal tissue concentrations of Ocuflox were elevated significantly by varying drug application methods and dosing schedules before PKP. Eyes receiving medication every 15 minutes for 4 hours had significantly higher levels of Ocuflox than those receiving the drug in six doses over 24 hours before surgery. Ocuflox concentrations exceeded the MIC90 (minimum inhibitory concentration) for key ocular pathogens in essentially all cornea specimens studied. Conclusion: Ocuflox penetration was improved by administering it in a controlled setting at 15 minute intervals over 4 hours. The drug provided high tissue levels in both the cornea and aqueous humor, which together with its broad range of antibacterial coverage, should make it a good choice for prophylactic treatment.

Postkeratoplasty Crystalline Deposits Mimicking Bacterial Infectious Crystalline Keratopathy

Three corneal transplant patients developed white, crystalline, anterior stromal lesions in their grafts while receiving long-term topical corticosteroid therapy. A presumed diagnosis of infectious crystalline keratopathy was made in each case. However, histologic examination of the lesions failed to show gram-positive cocci. A fungal infiltrate was present in the first two patients, and calcium deposits produced the lesion in the third patient.

Automated lamellar keratomileusis in situ for myopia.

BACKGROUNDnKeratomileusis in situ, particularly automated lamellar keratoplasty, is a commonly performed technique of keratomileusis in the United States.nnnMETHODSnA single center consecutive series of 152 eyes undergoing keratomileusis in situ for myopia was analyzed. Spherical equivalent refractions were compared before and after surgery. The standard nomogram supplied with the automatic corneal shaper (Chiron Vision Corp, Irvine, Calif) was used. The mean of preoperative myopia treated was -9.30 +/- 3.10 diopters (D) (range, -5.12 to -22.75 D).nnnRESULTSnOf the 144 eyes with 1 month follow up, 30 (21%) were within 0.50 D of the planned correction at 1 month, 54 (38%) were within 1.00 D, and 97 (67%) were within 2.00 D. At 6 or more months follow up, 51 of 68 eyes (75%) achieved uncorrected visual acuity of 20/40 or better and 13 of 68 (19%) 20/20 or better when eyes with macular degeneration and amblyopia were removed. Forty-six of 78 eyes (59%) with 6 months or greater follow up required retreatment procedures to correct residual myopia or astigmatism. Multiple regression analysis explained 40% of the variation between attempted correction and postoperative results. An overall 5% shift of refraction in the myopic direction occurred between 1 and 6 months. Of the 110 eyes with both 1- and 3-month examinations, the spherical equivalent refraction changed between these time intervals by 1.00 D or more in 54 (49%) eyes; and 11 (31%) eyes changed by 1.00 D or more between the 3- and 6-month examinations. Although 6% of eyes lost 2 or more lines of spectacle-corrected visual acuity, 11% gained 2 or more lines.nnnCONCLUSIONnMyopic keratomileusis in situ using the automated lamellar keratoplasty technique appears to be a safe and most effective procedure to reduce moderate to high myopia. However, the predictability of the procedure needs improvement.

One-year Results of a Prospective Multicenter Study of the Casebeer System of Refractive Keratotomy

Purpose: To evaluate the clinical results, predictability, stability, safety, and the patient satisfaction after refractive keratotomy for the correction of myopia and astigmatism using a defined protocol (the Casebeer system). Methods: The authors enrolled 324 patients (615 eyes) in a prospective study conducted by 18 surgeons. All procedures were performed using ultrasonic pachymetry with the diamond knife blade set at a length of 100% of the temporal paracentral corneal thickness reading and four to eight centripental (Russian style) incisions with or without fixation of the globe. Straight transverse incisions were done for astigmatism in 222 (36%) eyes. One to eight repeated operations (enhancements) were done on 241 (39%) eyes. Results: Mean baseline cycloplegic refraction was -3.68 ± 1.59 diopters (D) (range, -0.88 to -8.25 D). One-year data were available for 546 eyes (89%). At 1 year, mean spherical equivalent cycloplegic refraction was -0.27 ± 0.78 D (range, -3.13 to +3.00 D). There were 373 (68%) eyes with a refraction of ±0.50 D, and 483 eyes (89%) within ±1.00 D of emmetropia. Ten eyes (2%) were overcorrected by more than 1.00 D. Mean baseline refractive cylinder was 1.01 ± 0.75 D (range, 0–5.75 D); at 1 year, the mean cylinder was 0.40 ± 0.55 D (range, 0–2.50 D). Uncorrected visual acuity was 20/20 or better in 297 (54%) eyes and 20/40 or better in 93%. Six eyes (11%) lost two to three lines of spectacle-corrected visual acuity; the worst visual acuity was 20/30. Of patients responding to a standardized questionnaire, 320 (77%) wore no spectacles for distance or near vision; there was a significant increase in glare and fluctuation of vision from baseline; and 247 (90%) were very satisfied with the outcome. Conclusions: Refractive keratotomy using radial incisions with or without transverse incisions and following the Casebeer system effectively reduces and often eliminates myopia and astigmatism with a high degree of safety. Enhancement surgery was required in 39% of eyes. Glare and fluctuation of vision increased postoperatively but were rated mild, and patient satisfaction was high.

Intraocular complications associated with the Dubroff anterior chamber lens

Abstract We examined a series of 53 consecutive eyes from which Dubroff‐style anterior chamber lenses were explanted. The mean time from implantation to explantation was 46.21 months (range six to 99 months). Problems leading to explantation included bullous keratopathy (83%), glaucoma (51 %), chronic cystoid macular edema (40%), and iritis (13%). Molteno valves were required in 9% of eyes. Progressive anterior synechias resulted in intraocular lens displacement against the cornea in 19%. The Dubroff lenses caused problems similar to those previously observed with closed‐loop anterior chamber lenses but had a higher incidence of severe glaucoma and progressive peripheral anterior synechias.