Faculty Bibliography

PURPOSE: To present the microbial spectrum and susceptibilities of isolates in endophthalmitis following penetrating keratoplasty. DESIGN: Interventional case series. METHODS: The 1,074 consecutive cases of endophthalmitis presenting to Wills Eye Hospital between 1989 and 2000 were reviewed. Fourteen patients with endophthalmitis after penetrating keratoplasty were identified, and vitreous biopsy isolates from these patients were examined. RESULTS: Eleven (78.6%) of 14 vitreous samples were culture-positive, and two others (14.3%) had organisms viewed on pathology specimen, for a total of 13 (92.9%) organism-proven cases of endophthalmitis. Isolates included 10 (76.9%) gram-positive cocci (six Streptococcus sp., three Staphylococcus sp., one identified on pathology specimen only) and three (23.1%) gram-negative organisms (Proteus mirabilis, Serratia marcescens, one identified on pathology specimen only). Susceptibilities to organism-appropriate antibiotic testing are reported, including cefazolin (six of eight, 75.0%), ciprofloxacin (four of seven, 57.1%), nafcillin (four of six, 66.7%), and vancomycin (seven of seven, 100.0%). CONCLUSION: This is the largest series on microbial susceptibilities in postpenetrating keratoplasty endophthalmitis. We report a high percentage of culture-positivity, and a high incidence of gram-positive species, and in particular Streptococcus species, with all tested gram-positive organisms susceptible to vancomycin

OBJECTIVE: To review the available evidence for the use of confocal microscopy in diagnosing infectious keratitis and for other applications for ophthalmic practice. METHODS: A MEDLINE search of the peer-reviewed literature for the years 1990 to 2001 yielded 94 citations. The search was limited to studies of human subjects published in English with abstracts. The Ophthalmic Technology Assessment Committee Cornea Panel evaluated these 94 articles for possible clinical relevance and selected 51 (54%) for content review by the panel members. Of these 51 articles, 24 were selected for the panel methodologist to review and rate according to the strength of evidence. RESULTS: Of the 24 articles, 21 (87.5%) were classified as case reports or case series and were rated as level III evidence. Three articles were classified as independent, masked, or objective comparisons performed in a narrow spectrum of patients or in a nonconsecutive series of patients and were rated as level II evidence. No studies were rated as level I evidence, defined as an independent masked comparison of an appropriate spectrum of consecutive patients. CONCLUSION: Confocal microscopy is a new technology with clinical applications in ophthalmology. Although confocal microscopy has been used in other fields of medicine, the optical transparency of the cornea and other structures of the eye provides a unique opportunity to apply this technology. The targeted literature review of 24 articles found no level I studies to support the use of confocal microscopy in the management of eye disorders. Three level II studies pertained to promising clinical applications of the confocal microscope and provided evidence that supports the use of confocal microscopy as an adjunctive modality for diagnosing Acanthamoeba keratitis. The remaining 21 articles, rated as level III evidence, focus on the use of confocal microscopy to facilitate the diagnosis of infectious keratitis, including amoebic and fungal, but currently there are no definitive studies of its role in the differential diagnosis of this condition. There are also level III studies that support the use of the confocal microscope in refractive surgery. Facilitating the diagnosis of infectious keratitis and applying the confocal microscope to refractive surgery may hold the greatest promise of this new technology

PURPOSE: To report two cases of Descemet membrane detachment associated with hemorrhage after alkali burn to the cornea. DESIGN: Observational case reports. METHODS: We describe two patients with detachment of Descemet membrane associated with hemorrhage after alkali burns to the cornea. RESULTS: Patient 1 received a splash of caustic soda to the face. Descemet membrane detachment with hemorrhage was present. An attempt at reattachment using intraocular gases failed. Patient 2 sustained a chemical burn secondary to an airbag injury. A thickened, detached Descemet membrane associated with a hyphema was evident. CONCLUSIONS: Detachments of Descemet membrane associated with alkali burns are often accompanied by irreversible endothelial cell damage

PURPOSE: To report a case series of contact lens-related corneal ulcers in compliant patients with no apparent predisposing factors. DESIGN: Retrospective case series. METHODS: Charts of 70 patients with contact lens-related corneal ulcers from July 1999 to June 2002 were reviewed. Lens care hygiene and method of disinfection, as well as frequency of lens replacement, were recorded. Only patients who followed recommended guidelines for contact lens wear were included in the study. RESULTS: Of the 70 patients, 21 (30%) developed corneal ulcers despite being compliant with the guidelines for contact lens wear. All patients used multipurpose solutions for cleaning, disinfecting, and storing daily wear soft contact lenses. CONCLUSION: Standard lens care hygiene does not seem to be sufficient in preventing the development of corneal ulcers in patients using conventional and frequent replacement daily wear soft contact lenses

PURPOSE: To evaluate the presentation, treatment, and disease course of Thygeson's superficial punctate keratitis. DESIGN: Observational case series. PARTICIPANTS: Forty patients, diagnosed and managed with Thygeson's superficial punctate keratitis between January 1, 1992, and December 31, 2001, on the Cornea Service at Wills Eye Hospital. METHODS: Retrospective chart review. MAIN OUTCOME MEASURES: Patient demographics, symptoms, visual acuity, ophthalmic examination, management, duration of disease, and length of follow-up. RESULTS: At the time of presentation, the mean patient age was 28.7 years. The most common presenting symptoms included photophobia, blurred vision, and irritation. Thirty of 38 patients without a history of decreased vision (78.9%) initially were seen with visual acuities in both eyes of 20/30 or better. The 8 (21.1%) remaining patients all had visual acuities between 20/40 and 20/50; improvement in vision with treatment was noted in all 3 observed at our institution. Six patients (16%) had unilateral disease, whereas another 2 patients had bilateral involvement develop after unilateral presentation. Thirty-nine patients (97.5%) were treated with topical steroids at some point in their disease course. The patient not managed with steroids was only seen once and was managed with artificial tears for mild symptoms. In addition to steroids, a patient was treated for recurrent episodes with extended-wear contact lens, and another patient was started on topical cyclosporine because of an inability to be tapered off topical steroids. The average duration of disease in the 15 patients who were observed for more than a single year was 11.1 years. CONCLUSIONS: Thygeson's superficial punctate keratitis is a potentially chronic condition, which might affect people of all ages for years to decades. Corticosteroids are the mainstay of treatment, with extended-wear contact lens and topical cyclosporine reserved as secondary agents

OBJECTIVE: To evaluate the effectiveness of more than 12 months of oral acyclovir therapy in reducing recurrences of ocular herpes simplex virus. METHODS: We retrospectively compared ocular herpes simplex virus recurrence in 2 groups of patients. In group 1, patients used oral acyclovir for at least 12 months and then discontinued the treatment. In group 2, patients received the treatment for at least 18 months. We compared recurrences when both groups were using acyclovir (period 1) and when only group 2 was receiving the drug (period 2). Statistical analysis was performed with the t test, chi2 test, and Kaplan-Meier method. RESULTS: Group 1 had 18 patients and a mean +/- SD follow-up of 45.2 +/- 22.2 months. Group 2 had 22 patients and a mean +/- SD follow-up of 42.4 +/- 30.2 months. Six patients (33%) in group 1 and 4 patients (18%) in group 2 had recurrence in period 1 (P =.3). In period 2, 14 patients (78%) in group 1 and 8 patients (36%) in group 2 had recurrence (P =.01). Mean +/- SD recurrence-free survival in period 2 was 15.3 +/- 5.5 months in group 1 and 37.3 +/- 6.3 months in group 2 (P =.001). CONCLUSIONS: Long-term oral acyclovir use seems to remain effective in decreasing the number of ocular herpes simplex virus recurrences beyond 12 months