Antibacterial effectiveness of ciprofloxacin 0.3% ophthalmic solution in the treatment of bacterial conjunctivitis.

Two hundred eighty-eight cases of culture-proven bacterial conjunctivities were evaluated as part of two multicentered, randomized, prospective clinical studies comparing the antibacterial efficacy of topically administered ciprofloxacin 0.3% either with a placebo or with tobramycin 0.3%. In the first study, ciprofloxacin was significantly (P less than .001) more effective than the placebo. It eradicated or reduced the various bacterial pathogens in 93.6% of patients, compared to 59.5% for the placebo. In the second study, ciprofloxacin (94.5%) and tobramycin (91.9%) were equally effective. Topically applied ciprofloxacin eradicated or reduced all isolated bacterial species, attesting to its broad antibacterial spectrum and its potential usefulness in treating external ocular infections.

Clinical evaluation of ciprofloxacin 0.3% ophthalmic solution for treatment of bacterial keratitis.

A multicenter, prospective clinical study of 148 culture-proven cases of bacterial keratitis, treated with ciprofloxacin 0.3% ophthalmic solution, compared its clinical and antibacterial efficacy with the standard therapy regimen of each investigator. Most often, this consisted of topically administered fortified cefazolin (33 mg/ml) and fortified gentamicin or tobramycin (14 mg/ml). Two control groups were studied: (1) patients treated while the ciprofloxacin study was ongoing (not enrolled group); and (2) patients treated during the year before initiation of the ciprofloxacin study (historical group). Treatment with ciprofloxacin yielded a 91.9% success rate. Standard therapy yielded an 88.2% success rate among not enrolled control patients and an 88.3% success rate among the historical control patients. No serious side effects accompanied ciprofloxacin administration. In vitro susceptibility testing showed ciprofloxacin to be highly effective against bacterial corneal pathogens. These findings suggest that ciprofloxacin 0.3% is safe and effective as a single agent for the treatment of bacterial keratitis.

Bilateral acute corneal calcification.

A 38-year-old man with brittle, juvenile onset diabetes mellitus and bilateral severe dry eyes with recurrent corneal ulcers developed atypical band-shaped calcifications of both corneas during a 24-hour period. Serum calcium, phosphate, and carbon dioxide levels all were within normal limits. The patient was mildly uremic but was not in renal failure. When EDTA chelation failed to clear the deposits, partial keratectomies were performed in both eyes and the specimens were examined by light and electron microscopy, including energy dispersive x-ray analysis. Microscopic studies revealed an atypical calcific keratopathy which involved neither Bowman's layer nor the most superficial stromal lamellae. The deposits were confined to deeper lamellae in the anterior stroma and by electron microscopy were composed of extracellular crystalline aggregates. Energy dispersive x-ray analysis of these aggregates confirmed the presence of calcium and phosphate. Corneal dessication appeared to be a major contributing factor in the rapid formation of these deposits.

Fluorometholone acetate: clinical evaluation in the treatment of external ocular inflammation.

Separate, randomized, double-masked clinical studies were conducted to determine the therapeutic efficacy of fluorometholone acetate, a new ophthalmic corticosteroid formulation, in suppressing external ocular inflammation (conjunctivitis, episcleritis, scleritis). Fluorometholone acetate 0.1% was compared to fluorometholone 0.1%, and the acetate formulation was found to be significantly (p = 0.03) more effective. Fluorometholone acetate 0.1% also was compared to prednisolone acetate 1.0%; there was no significant difference (p = 0.49) between these two corticosteroids in their ability to suppress external ocular inflammation. It appears that alteration of fluorometholone from its alcohol base to its acetate derivative changes the drug from a moderately effective to a highly effective anti-inflammatory agent.

Tobramycin in external eye disease: a double-masked study vs. gentamicin.

A double-masked randomized study was conducted at four centers to compare the efficacy and safety of tobramycin and gentamicin ophthalmic ointment in the treatment of superficial external eye disease. Seventy-seven patients with blepharitis and/or conjunctivitis were evaluated for safety, and 56 of the 77 individuals also qualified for evaluation of drug efficacy. After a 10 day treatment regimen, 97% of the tobramycin treated patients and 91.3% of the gentamicin treated patients were clinically cured or improved. Antibacterial effectiveness studies in the conjunctiva showed that tobramycin eradicated or controlled 87.8% of the bacterial infections vs. 77.4% for gentamicin. There was also a 9.3% adverse reaction rate with tobramycin vs. 17.6% with gentamicin. Primary symptoms consisted of erythema, injection, discomfort and itching. All adverse reactions were mild and cleared upon discontinuation of the study drug. While the trends seem to favor tobramycin, no difference was statistically significant at the p less than or equal to 0.05 level. These results indicate that tobramycin is a clinically effective and safe topical antibiotic and that it is comparable to gentamicin for topical treatment of bacterial external eye infections. It also may be better tolerated than gentamicin.

Management of inflammation in the cornea and conjunctiva.

The ability of the cornea to react to inflammatory stimuli is limited, and in most instances the polymorphonuclear leukocyte is primarily responsible for corneal damage. Of currently available drugs, corticosteroids are the most effective for the non-specific control of these inflammatory cells. Principles for obtaining maximal therapeutic effect from minimal amounts of the drug are presented. The use of corticosteroids in the treatment of a keratitis caused by various types of replicating microbial agents is discussed. The response to therapy of inflammatory processes in the conjunctiva seemingly differs from the response in the cornea. Suggestions are offered for corticosteroid use in conjunctivitis.

Topical antibiotic therapy of Pseudomonas aeruginosa keratitis.

The in vivo antibacterial effectiveness in the rabbit cornea of several commercially available ophthalmic antibiotic preparations was determined against a single strain of Pseudomonas aeruginosa isolated from a human corneal ulcer. Each antibiotic was instilled topically at hourly intervals, and the number of residual viable organisms in the cornea subsequently was ascertained. In vivo measurements correlated well with in vitro data and with generally held clinical impressions. Three antibiotics, gentamicin sulfate, polymyxin B sulfate, and colistin sulfate, suppressed corneal growth of P aeruginosa in commercially available concentrations. Gentamicin was slightly more effective than polymyxin B; both drugs were substantially more effective than colistin. Formulations of gentamicin and polymyxin B containing approximately four times the quantity of drug found in commercial preparations eliminated this P aeruginosa strain from the cornea much more rapidly than did the commercial preparations.

Quantitation of bacterial infection and antibiotic effect in the cornea.

We report an experimental model that allows objective quantitation of bacterial keratitis. The model permits direct measurement of the number of viable organisms in the cornea after varying periods of in vivo growth. The size of the inoculum used to produce the corneal infection is critical, and the experimental organism must be standardized for its growth characteristics in the cornea. The end point is an objective one, productive of numerical data that can be subjected to statistical analysis. The findings are highly reproducible and the system is sufficiently sensitive to indicate the ability of a topically administered antibiotic to reduce the number of viable organisms in the cornea of an outbred rabbit population.

Human conjunctivitis. II. Treatment.

One hundred forty-three patients (207 eyes) with conjunctivitis or blepharoconjunctivitis were investigated to determine (1) the safety of topical corticosteroid therapy and the relative efficacy of formulations of increasing potency and (2) the effectiveness of a steroid-antibiotic preparation compared to each of its components alone and to a placebo. The corticosteroids were equally effective in suppressing conjunctival inflammation; all were more effective than the placebo. Active conjunctivitis was controlled more readily by those preparations containing a steroid, both alone and in combination. The corticosteroid alone (dexamethasone) was more effective in producing inactivation of conjunctivitis than the antibiotic alone ( a mixture of neomycin sulfate and polymyxin B sulfate). This observation remained unchanged when cases of Staphylococcus aureus conjunctivitis were analyzed separately. No serious complications resulted from any treatment regimen.

In vivo photomicrography of the corneal endothelium.

A technique and apparatus for observing and photographing the corneal endothelium in vivo at a magnification of approximately times 200 is described. The method is suitable for animal experimentation and for diagnostic observation and clinical research in humans.