Paul B. Donzis

Microbial Contamination of Contact Lens Care Systems

We examined the contact lens care systems of 100 asymptomatic patients who used hard or soft contact lenses for correction of refractive errors for the presence of bacteria, fungi, Acanthamoeba, and endotoxin. Of 100 patients, 52 had contaminated contact lens care systems. Sixteen of 126 bottles (13%) of commercial contact lens care solutions were contaminated. Contaminated commercial solutions were opened and used for a longer period of time than uncontaminated solutions. Contamination was not found in bottles of preserved commercial solutions that were opened and used for less than 21 days. All 12 bottles of homemade saline were contaminated with bacteria, and Acanthamoeba was isolated from two of these bottles. Pseudomonas was found in the care systems of 12 patients. Bacillus species, which form spores resistant to heat, were found in the care systems of seven patients. Endotoxin, which is also resistant to heat, was detected in nine of 35 care systems (26%) tested. Potential pathogens were isolated from the conjunctiva of six patients.

Successful Medical Management of Acanthamoeba Keratitis

Seven patients with documented Acanthamoeba keratitis were treated with prolonged and intensive triple antiamoebic therapy consisting of topical neomycin-polymyxin B-gramicidin, propamidine isethionate 0.1%, and miconazole nitrate 1%. Additionally, five patients were treated with topical corticosteroids. Six of seven patients were cured of Acanthamoeba keratitis with medical therapy alone, one patient required therapeutic penetrating keratoplasty to eradicate the infection. Two patients underwent penetrating keratoplasty to improve their vision after medical therapy. Our series differs from previous reports in that triple antiamoebic therapy was used in all seven patients and was successful in both early and advanced cases of Acanthamoeba keratitis. Prolonged and intensive topical therapy with these three antiamoebic drugs may be an effective mode of therapy for Acanthamoeba keratitis.

Discoid Lupus Erythematosus Involving the Eyelids

Of two patients with discoid lupus erythematosus with eyelid involvement, one, a 42-year-old man, had a one-year history of persistent periorbital edema and a violaceous discoloration as the sole manifestation. Although treatment with corticosteroids and antihistamines failed to produce improvement, the patient had an excellent clinical response to systemic hydroxychloroquine therapy. Histologic examination with immunofluorescent staining demonstrated deposition of immunoglobulins at the dermoepidermal junction. The second patient, a 37-year-old woman, had a hyperpigmented lesion on her forearm as the initial symptom but later developed similar lesions elsewhere, including her lower eyelid. Treatment with hydroxychloroquine again produced an excellent response.

Microbial Analysis of Contact Lens Care Systems Contaminated With Acanthamoeba

We analyzed bacterial and fungal contamination within the contact lens care systems of ten patients who had Acanthamoeba detected within their care systems. Seven patients had Acanthamoeba keratitis, one had Pseudomonas keratitis, and the remaining two were asymptomatic. Gram-negative bacteria were found in all ten care systems, and Pseudomonas was found in six. Bacillus species, the only gram-positive bacteria isolated, were found in five systems. Fungi were isolated in six care systems. The use of homemade saline and the two-cup method of peroxide disinfection were associated with microbial contamination. Acanthamoeba organisms were found only in contact lens cases or solutions that also had bacterial and in many cases fungal contamination, suggesting that the presence of bacterial and fungal contamination within the contact lens care system may be an important element for the survival and growth of Acanthamoeba.

Corneal ulcers associated with disposable hydrogel contact lenses

Four patients developed corneal ulcers associated with the use of disposable extended-wear hydrogel contact lenses. Bacteria were recovered from corneal ulcers in three of the patients. Three patients discarded their contact lenses after ten or more days of extended wear; the corneal ulcers in these patients developed toward the end of the wearing cycle. The fourth patient removed her contact lenses every two days for cleaning and disinfection and discarded them for a new pair on a weekly basis. Improper lens hygiene was noted in only one patient. All corneal ulcers responded to antibiotic treatment. In three patients visual acuity returned to normal, but scarring of one patients cornea resulted in a visual acuity of 20/60.

Bacillus Keratitis Associated With Contaminated Contact Lens Care Systems

We examined two soft contact lens wearers who developed keratitis associated with Bacillus contamination of their contact lens care systems. Patient 1 developed a corneal ulcer caused by B. subtilis, and Patient 2 demonstrated multiple, diffuse, punctate corneal epithelial opacities associated with B. cereus contamination in the contact lens and lens case compartment. The contact lens cases of both patients contained Bacillus spores that survived multiple heat disinfection treatments. Three different contact lens chemical disinfection systems used for the minimum recommended time failed to kill the Bacillus organisms.

Sodium Hyaluronate (Healon®) in the Surgical Repair of Descemet's Membrane Detachment

Two cases of Descemets membrane detachment are presented. In both cases, sodium hyaluronate (Healon) was successfully used to repair the detachment surgically. The viscoelastic property of sodium hyaluronate allows it to move Descemets membrane easily into proper position and maintain it there post-operatively. Sodium hyaluronate left in the anterior chamber can cause an increase in intraocular pressure and prophylactic measures, such as diamox and timoptic should be used in these cases.

Visual field loss resulting from cervical chiropractic manipulation

PURPOSE To report a complication of chiropractic cervical manipulation. METHOD Case report. A healthy 39-year-old woman developed sudden left peripheral visual field loss after chiropractic neck manipulation. RESULTS Visual field testing disclosed a left superior homonymous hemianopsia. A magnetic resonance imaging scan performed the day of the event disclosed acute infarction of the ventromedial aspect of the inferior right occipital lobe. CONCLUSION Cerebral infarct may occur as a result of chiropractic neck manipulation.

Prediction of Aphakic Refractive Error in Children

Formulas created to predict the optical requirements of the aphakic eye have been tested mainly in adult eyes. The accuracy of these formulas in shorter pediatric aphakic eyes was examined using retrospective analysis of 17 aphakic pediatric patients. The Sanders-Retzlaff-Kraff contact lens formula, used previously to predict required lens powers for epikeratophakia, consistently underestimated the required aphakic correction in the shorter eyes, which may have been responsible in part for the large undercorrections obtained previously in patients under one year of age. The Hoffer-Colenbrander and Binkhorst theoretical formulas, Donzis-Kastl-Gordon percentage change formula, and a linear regression formula derived from the present data (LIN), were significantly more accurate. The differences between these formulas were not significant. The use of one of these formulas should facilitate prediction of required epikeratophakia lenticule power or intraocular lens power in young children.

Corneal Ulcer Associated with Contamination of Aerosol Saline Spray Tip

PURPOSE To report a complication of aerosol saline use in a contact lens wearer. METHODS Case report. A 57-year-old woman who used soft contact lenses on an extended-wear basis developed a unilateral Pseudomonas corneal ulcer associated with the use of preservative-free aerosol saline. RESULTS The solution inside the aerosol can was free of microbial contamination. The spray tip, however, was contaminated with P aeruginosa. CONCLUSIONS Aerosol spray cans may minimize contamination of the solution inside the can. The spray tip is still susceptible to microbial contamination, especially with continued use of the solution over an extended period of time.