Harold R. Katz

Comparison of Topical Ciprofloxacin to Conventional Antibiotic Therapy in the Treatment of Ulcerative Keratitis

We evaluated the efficacy of ciprofloxacin (3 mg/ml) as the sole topical antibiotic used to treat infectious keratitis in 14 patients. We compared the ciprofloxacin-treated group to a retrospective control group of 30 consecutive culture-positive patients treated with conventional therapy in which cefazolin (50 mg/ml) and fortified gentamicin sulfate (9.1 mg/ml) solutions were used. We found no remarkable difference between the control group and the ciprofloxacin-treated group regarding patient age, risk factors, need for hospitalization, and virulence of organism isolated. The average time to healing in culture-positive ciprofloxacin-treated patients was 34 +/- 33 days vs 45 +/- 71 days in the control group and this difference was not statistically significant. The duration of antibiotic therapy in the culture-positive ciprofloxacin-treated group was 27 +/- 15 days vs 33 +/- 50 days in the control group. Four of the 30 control patients required modification of their antibiotic regimen, whereas no ciprofloxacin-treated patient required a change. Ciprofloxacin appears to be an effective single agent in the treatment of ulcerative keratitis.

The role of cultures in the management of ulcerative keratitis.

PURPOSE To ascertain the importance of routine cultures and gram stains in the management of ulcerative keratitis. METHODS We retrospectively reviewed 119 consecutive corneal ulcers seen at Sinai Hospital of Baltimore. Cultures were obtained of the corneal ulcer and of the lids and conjunctivae of both eyes. Gram stains were performed by the hospital microbiology department on corneal scrapings from each ulcer. RESULTS Positive corneal cultures were obtained from 56 eyes (47.1%). Initial antibiotic therapy was changed based on culture results in 14.3% of culture-positive eyes that demonstrated a worsening clinical course. Gram stains were negative in all cases. The sensitivity and specificity of the lid and conjunctival cultures were determined. CONCLUSIONS Corneal cultures are important in the management of ulcerative keratitis. Lid and conjunctival cultures have low sensitivity and specificity.

Absorption of Topical Moxifloxacin Ophthalmic Solution Into Human Aqueous Humor

Purpose: To investigate the absorption of moxifloxacin into human aqueous humor after administration of moxifloxacin hydrochloride ophthalmic solution, 0.5% as base. Methods: Cataract patients were randomly allocated to receive 1 drop every 15 minutes for 4 doses before surgery (group 1) or 1 drop 4 times per day on the day before surgery plus the same preoperative regimen as group 1 (group 2). The last dose was administered 0.25, 0.50, 1, 2, or 3 hours before aqueous humor sampling. Samples from 30 patients per group were analyzed by a validated HPLC/MS/MS method. Results: For group 1, the mean ± SD Cmax was 1.50 ± 0.75 μg/mL and occurred at 0.5 hour after dosing. The mean Cmax for group 2 was 1.74 ± 0.66 μg/mL and was reached at 1 to 2 hours. Mean AUC0-3h for groups 1 and 2 were 3.16 ± 0.29 and 4.41 ± 0.48 μg·h/mL, respectively. The difference in AUC0-3h was statistically significant (P = 0.04), but the difference in Cmax was not. Conclusions: Topical moxifloxacin was well absorbed. Maximum moxifloxacin concentrations were approximately 30 times higher than the median MICs for common pathogens in bacterial endophthalmitis, indicating that either regimen may provide sufficient concentrations to prevent postoperative endophthalmitis.

COMPARATIVE EFFICACY OF TOPICAL MOXIFLOXACIN VERSUS CIPROFLOXACIN AND VANCOMYCIN IN THE TREATMENT OF P. AERUGINOSA AND CIPROFLOXACIN-RESISTANT MRSA KERATITIS IN RABBITS

Purpose: To evaluate the in vivo efficacy of topical moxifloxacin 0.5% versus ciprofloxacin 0.3% in the treatment of Pseudomonas aeruginosa keratitis and topical moxifloxacin 0.5% versus vancomycin 50 mg/mL in the treatment of ciprofloxacin-resistant, methicillin-resistant Staphylococcus aureus (MRSA) keratitis in rabbits. Methods: Experimental bacterial keratitis was induced in rabbits by corneal intrastromal injection. Infection proceeded for 12 hours, after which topical antibiotics were applied hourly for 12 hours. Corneal homogenates were plated with serial dilutions for quantitative bacteriology. Results: Both moxifloxacin and ciprofloxacin performed significantly better than control in the treatment of Pseudomonas aeruginosa keratitis (P = 0.0046 and 0.0069, respectively); there were no significant differences between these 2 drugs in bactericidal activity (P = 0.1120). Moxifloxacin performed significantly better than control in the treatment of ciprofloxacin-resistant MRSA (P = 0.0321) keratitis, and vancomycin showed a trend toward statistical significance in performing better than control (P = 0.0576); there were no significant differences between these 2 drugs in bactericidal activity (P = 0.5205). Conclusions: Topical moxifloxacin 0.5% and ciprofloxacin 0.3% have similar efficacy in the treatment of Pseudomonas aeruginosa keratitis in rabbits. Topical moxifloxacin 0.5% and vancomycin 50 mg/mL have similar efficacy in the treatment of ciprofloxacin-resistant MRSA keratitis in rabbits. These results suggest a potential value for topical moxifloxacin as a broad-spectrum agent in the treatment of bacterial keratitis.

Late partial dislocation of a laser in situ keratomileusis flap

We report an apparently atraumatic asymptomatic flap dislocation 4 months after uneventful laser in situ keratomileusis (LASIK) in the right eye of a 43-year-old woman. The patient developed partial dislocation of the LASIK flap during the week after the 4 month examination. The LASIK flap was subsequently lifted to perform an enhancement, and the postenhancement course has been unremarkable. This case illustrates the potential susceptibility of LASIK flaps to dislocation either spontaneously or, more likely, after presumed minor trauma as late as 4 months after the original procedure.

Nd:YAG Laser Photo-induced Adhesion of the Corneal Epithelium

We retrospectively studied eight patients with recurrent corneal erosions treated with the Nd:YAG laser using 0.4- to 0.5-mJ pulses applied to the region of Bowmans layer through an intact epithelium. All eight patients had resolution of their symptoms after treatment. Mean follow-up time was 21.2 months (range, 12.6 to 36.6 months). A patient who was scheduled for diagnostic enucleation for a posterior choroidal mass consented to undergo this laser treatment with varied energy settings six days before his enucleation. His cornea was studied with specular microscopy, light microscopy, and transmission electron microscopy. Light microscopy of the cornea disclosed rare 100-microns defects in Bowmans layer with subjacent compaction of the anterior stromal lamellae. Electron microscopy showed minute foci of disruption in Bowmans layer with new collagen formation. Fine fibrils connected the basal epithelial cells to the new collagen. Nd:YAG laser photo-induced adhesion of the corneal epithelium may represent an effective treatment alternative for patients with recurrent corneal erosions.

Complications of Contact Lens Wear after Radial Keratotomy in an Animal Model

In 12 rabbits radial keratotomy was performed on one eye with no treatment to the contralateral eye. Cellulose acetate butyrate contact lenses were fitted bilaterally for extended wear. The eyes were monitored weakly for three weeks with a standardized slit-lamp grading method. Corneal neovascularization occurred earlier and progressed further in eyes that had radial keratotomy than in the control eyes (P less than .0025). These results suggested that patients who require contact lenses after radial keratotomy may be at higher risk for complications such as corneal neovascularization.

Intraoperative corneal pachymetry in eyes having radial keratotomy

Abstract We prospectively studied 45 eyes that had radial keratotomy for correction of myopia to determine whether significant changes in corneal thickness occurred during the surgical procedure and which paracentral corneal region was the thinnest consistently. We used a standard bidirectional technique with a diamond knife. The inferotemporal paracentral region was the thinnest most frequently (38% of eyes) both pre‐incision and post‐incision. However, each of the other paracentral regions measured the thinnest in a smaller percentage of eyes: temporal (28% pre‐incision and post‐incision); inferior (19% pre‐incision, 21 % post‐incision); nasal (11 % pre‐incision, 9% post‐incision); superior (4% pre‐incision and post‐incision). A statistically significant reduction in corneal thickness occurred intraoperatively in all regions.