Methicillin-resistant Staphylococcus aureus ulcerative keratitis after laser in situ keratomileusis.

We report the first case of methicillin-resistant Staphylococcus aureus (MRSA) ulcerative keratitis after routine bilateral laser in situ keratomileusis. Within 24 hours of initial ulceration the lamellar flap melted, disintegrating into necrotic fragments. Recognition of lamellar flap infections followed by immediate medical and surgical management is critical to preserving vision.

Communicating with laser vision correction patients.

Laser vision correction or LASIK has a long and excellent history with significant benefits and unlikely risks. Adequately educating patients should allay their fears and allow good candidates to enjoy the life changing benefits of improvement in the natural vision through laser vision correction.

The accuracy of finger tension for estimating intraocular pressure after penetrating keratoplasty.

BACKGROUND AND OBJECTIVE: Intraocular pressure (IOP) estimation by Goldmann tonometry is inaccurate in the immediate postoperative period after penetrating keratoplasty. For this reason, many corneal surgeons use a finger tension (FT) IOP estimation technique in the early post-keratoplasty period. The authors performed a prospective clinical study to evaluate the accuracy of this traditional technique. PATIENTS AND METHODS: FT estimates were performed by three experienced corneal surgeons on 68 patients on the first and second days after penetrating keratoplasty. These estimates were compared with MacKay-Marg (MM) tonometry readings for these patients. RESULTS: The mean confident FT from the pooled data of the three surgeons exceeded the MM reading by 5.0 mm Hg (22.6 vs. 17.6). The mean FT exceeded the MM reading by only 3.9 mm Hg for the most accurate surgeon. Some observers were significantly more accurate than others, however, lid edema and tenderness of the globe markedly diminished the FT accuracy of all of the observers at significance levels of P < .001 and P < .01, respectively. Among all of the FT estimates, in only one patient (2%) did the FT underestimate the MM reading by more than 10 mm Hg. CONCLUSION: The authors' results suggest that for some patients, and for some surgeons, the FT or digital method of IOP estimation remains useful for detecting elevated IOP early after corneal transplantation if the proper technique is used and substantial lid edema and patient discomfort are absent.

The antibacterial activity of topical anesthetics.

PURPOSE: Topical anesthetics are commonly used prior to obtaining bacterial cultures in ulcerative keratitis. We performed an in vitro study designed to test both the bacteriostatic and bactericidal effects of commercially available preserved topical anesthetic agents. METHODS: Proparacaine, tetracaine, cocaine, and sterile water solutions were applied to filter paper disks, which were then placed on Mueller-Hinton agar plates that had previously been inoculated with known quantities of Pseudomonas aeruginosa and Staphylococcus aureus. After 24 h of incubation, zones of inhibition were measured and recorded. RESULTS: Proparacaine strongly inhibited the growth of S. aureus at all concentrations (0.5%, 0.25%, 0.125%) and inhibited growth of P. aeruginosa at 0.5% and 0.25% but not at 0.125% concentration. Tetracaine also inhibited S. aureus at 0.5% and inhibited P. aeruginosa at 0.5% and 0.25% concentrations. Cocaine exhibited no inhibition of S. aureus and exhibited mild inhibition of P. aeruginosa growth only at the 4% concentration. CONCLUSIONS: The in vitro antibacterial effect of topical anesthetics suggests one possible reason why bacterial culture yields in clinical ulcerative keratitis are suboptimal. We propose that clinicians consider the use of a 1% or 2% cocaine solution instead of standard commercial topical anesthetics in the management of individual cases of ulcerative keratitis and in future clinical bacterial keratitis studies.

Topical mitomycin-C for pterygia: is single application appropriate?

BACKGROUND AND OBJECTIVE: Mitomycin-C has been shown to dramatically reduce pterygium recurrence rates; however, its use has been associated with serious complications, especially in higher cumulative doses. The authors investigated the safety and efficacy of progressively reducing dosages of mitomycin-C as an adjunct to pterygium surgery. PATIENTS AND METHODS: Four hundred eighty-one consecutive primary and recurrent pterygia were surgically excised in a prospective nonrandomized trial using five different mitomycin-C dosages. Recurrence was defined as fibrovascular tissue over the corneoscleral limbus onto clear cornea in the area of previous pterygium excision. RESULTS: Seventy-seven patients in a control group without mitomycin-C had a recurrence rate of 65% with a mean follow-up of 33 months. A group of 77 patients treated with 0.4 mg/ml of mitomycin-C, four times per day for 2 weeks, had a recurrence rate of 2.5% with 6 (10%) serious complications (mean follow-up 34 months). A group of 22 patients treated with 0.2 mg/ml of mitomycin-C, four times per day for 10 days, had a recurrence rate of 55% with 3 (7.3%) non-vision-threatening complications (mean follow-up 32 months). A group of 16 patients treated with 0.2 mg/ml of mitomycin-C intraoperatively for 3 minutes without conjunctival closure had a recurrence rate of 44% with no complications (mean follow-up 35 months). Finally, a group of 289 patients treated with 0.2 mg/ml of mitomycin-C intraoperatively for 3 minutes with conjunctival closure had a recurrence rate of 2.7% and no complications (mean follow-up 26 months). CONCLUSION: Although the authors' results with single application are encouraging, the use of mitomycin for pterygia remains controversial. The biologic potency of this agent, the duration of its action, and the dearth of large-scale controlled, randomized trials demand cautious individual judgment by the surgeon when considering the use of this potent drug.

Topical anesthetic abuse ring keratitis: report of four cases.

PURPOSE: We present the clinicopathologic correlations of two case and two other clinical cases of topical anesthetic abuse keratopathy that were originally diagnosed as Acanthamoeba keratitis because of ring keratitis presentation and characteristic history. METHODS: Four patients who were referred to us with suspected Acanthamoeba keratitis are included. Each was initially treated for amoebic keratitis, by using established protocols, and only later was the true origin (topical anesthetic abuse) uncovered. The clinical and surgical histories, pathologic analysis of the corneal specimens, and follow-up of < or = 4 years are included. RESULTS: Our four cases show another cause for ring infiltration of the cornea. Two cases resulted in corneal transplantation and multiple other medical or surgical treatments in an attempt to restore vision but had poor outcomes of finger-counting vision. Two other cases responded to intensive medical treatments with return of useful vision. Evaluation of the surgical specimens revealed a previously unpublished finding of near total cell death within the corneal stroma. CONCLUSION: Topical anesthetic abuse resulting in sight-threatening keratitis may be seen as a masquerade syndrome in many cases. Because of the often poor outcome, we must be aware of this entity, prevent abuse, and be vigilant in our prohibition of topical anesthetic for any therapeutic use.

Pneumococcal keratitis, bacteremia, and septic arthritis in an asplenic patient.

We report the case of a 66-year-old black woman who presented with concomitant acute infectious keratitis, bacteremia, and septic arthritis caused by Streptococcus pneumonia. The septic arthritis resolved rapidly with surgical drainage and intravenous antibiotics, but despite aggressive topical and intravenous antibiotic therapy for the infectious keratitis, the cornea perforated, the patient developed endophthalmitis, and the eye eventually was eviscerated. To the best of our knowledge this is the first reported case of this nature. This patient had undergone splenectomy > 50 years prior to developing these infections. Although the risk of serious infection in clinically significant bacteremia is greatest in the perioperative period after splenectomy, these patients are at increased risk of such events for a lifetime. Because encapsulated bacteria, especially Pneumococcus, pose the greatest risk of sepsis and infection in asplenic patients, pneumococcal vaccination of penicillin prophylaxis must always be considered in these patients. A careful and complete medical history and systemic evaluation remain a crucial element of the evaluation and management of serious infectious keratitis.

Cytomorphology of a mixed pigmented/nonpigmented pleomorphic adenoma of the ciliary body: a diagnostic pitfall in the evaluation of intraocular tumors.

Intraoperative cytology is an alternative and sometimes preferred method to frozen section in the rapid evaluation of surgical biopsies. This report describes the cytological, histological, and immunohistochemical features of a case of mixed pigmented/nonpigmented pleomorphic adenoma of the ciliary body with clinical and morphological features reminiscent of malignant melanoma. The characteristic cyto-histomorphology of this unusual tumor and its distinguishing features from malignant melanoma are discussed.

Anterior stromal puncture. Immunohistochemical studies in human corneas.

OBJECTIVE: To investigate the mechanism of action of corneal anterior stromal puncture (ASP) in humans. DESIGN: Immunocytochemical techniques were used to localize fibronectin, type IV collagen, and laminin in human corneas with bullous keratopathy, some of which had undergone ASP. Corneal specimens were obtained from transplant procedures performed in a related clinical study. SETTING: Outpatients in private practice settings. PATIENTS: Nine patients with recurrent erosion secondary to bullous keratopathy who were judged to be poor candidates for keratoplasty. INTERVENTIONS: Anterior stromal puncture was performed on each patient using a standardized needle, and corneal transplants were performed on patients whose erosions did not resolve after ASP. PRIMARY OUTCOME MEASURES: Subjective comfort and slit-lamp verification of resolution of rupture of bullae and erosions in patients who underwent ASP; Nomarski differential interference contrast photography, immunohistochemical staining, and light microscopy were applied to the corneal specimens. RESULTS: All three matrix glycoproteins were observed in the epithelial basement membrane of normal corneas. In patients with bullous keratopathy who did not undergo ASP, the epithelial basement membrane of the cornea did not stain with antibodies against human fibronectin, type IV collagen, or laminin. In patients with bullous keratopathy who underwent ASP, all three major proteins were present at the puncture sites and in the reactive subepithelial pannus adjacent to the puncture site. Epithelial basement membrane of untreated regions showed little or no staining. CONCLUSIONS: The results suggest that the absence of these extracellular matrix proteins in the epithelial basement membrane of patients with bullous keratopathy may be an important factor in the development of poor epithelial adhesion and secondary erosions. Anterior stromal puncture may promote epithelial reattachment, at least in bullous keratopathy, by stimulating the production of extracellular matrix proteins that are important in the attachment of epithelial cells to the underlying connective tissue. Epithelial-stromal reactions and the development of subepithelial fibrosis may also play a role in reestablishing epithelial attachment.

Serious complications of topical mitomycin-C after pterygium surgery.

BACKGROUND: The use of topical mitomycin (mitomycin-C) as a medical adjunct to pterygium and glaucoma surgery is increasing. METHODS: The authors report on a series of 10 patients who experienced serious, vision-threatening complications associated with the use of this drug after pterygium surgery. RESULTS: Complications included severe secondary glaucoma (4 patients), corneal edema (3 patients), corneal perforation (1 patient), corectopia (2 patients), iritis (8 patients), sudden onset mature cataract (2 patients), scleral calcification (1 patient) and incapacitating photophobia and pain (8 patients). Two patients required penetrating keratoplasties and a third required three lamellar keratoplasties. Another patient underwent four additional surgeries including a conjunctival Z-plasty, scleral patch grafting, and conjunctival autografting before his intractable pain and photophobia resolved 15 months after the original surgery. Because of these complications, 6 patients required a total of 20 return visits to the operating room after their original pterygium surgery. In 5 eyes, visual acuity remained at 20/200 or less. Three of the six patients with the most severe complications had concomitant chronic external diseases (rosacea [3 patients], ichthyosis [1 patient], keratitis sicca [1 patient]). CONCLUSION: The authors urge extreme caution in the use of mitomycin. If mitomycin is used, the lowest possible concentration should be applied for the shortest time period in an effort to avoid these complications. A prospective multicenter study of the ophthalmic use of this medication is needed.

Ocular hydrofluoric acid burns.

A 30-year-old man sustained exposure of his eyes, face, and neck involving 4% of body surface area to hydrofluoric acid. He was treated with immediate lavage and topical calcium gluconate. Because free fluoride ions from ocular and facial exposures can form complexes with body stores of calcium and magnesium, the patient was transferred to a burn unit for cardiac and electrolyte monitoring. He was also treated with calcium gluconate skin injections, pulmonary nebulizer therapy, and topical antibiotics and corticosteroids. In another case, a 25-year-old man with less severe exposure to hydrofluoric acid was treated as an outpatient with topical antibiotics, corticosteroids, and cycloplegia. If an ophthalmologist is the first to treat a patient with chemical exposure, the history of hydrofluoric acid exposure must be obtained, and the burn team and other medical specialists must be quickly consulted to avoid potentially fatal complications.

Giant papillary conjunctivitis and meibomian gland dysfunction blepharitis.

In this prospective pilot study we saw 42 consecutive giant papillary conjunctivitis (GPC) patients (80 eyes), all of whom were found to have some meibomian gland dysfunction blepharitis. Severity of GPC at presentation correlated with severity of meibomian gland dysfunction blepharitis (Kendall's tau b averaged 0.246 across the adjusted statistical analyses). Thirty-two patients (63 eyes) were refit after treating meibomian gland dysfunction blepharitis. Twenty-eight of these patients (55 eyes; 87%) continue to wear contact lenses, maintaining an improvement in GPC (mean follow-up 21 months; range 11-36 months). We hypothesize that meibomian gland dysfunction blepharitis may play a role in the pathogenesis of GPC and suggest that a large, controlled, multi-observer study be performed to further investigate this possible association.

Keratoconus after penetrating keratoplasty.

Signs of keratoconus, including Munson's sign, apical thinning, and Vogt's striae, developed in a 41-year-old woman 6 years after successful penetrating keratoplasty. Screening donor corneas for ectatic diseases may prevent such occurrences.

Anterior stromal puncture for recurrent erosion: further experience and new instrumentation.

Anterior stromal puncture has recently been proposed as a new treatment for recalcitrant cases of recurrent corneal erosion. Concerns about the risks of corneal perforation and scarring, as well as doubts regarding its efficacy have prevented many patients from benefiting from this procedure. We introduce a new, inexpensive, commercially available instrument designed to standardize this technique, minimize scarring, and prevent corneal perforation. In a clinical trial involving 25 consecutive patients with recurrent erosions resistant to vigorous conservative treatment, the first 11 patients underwent stromal puncture in which a straight tuberculin needle was used; the following 14 were treated with a newly designed prototype needle. All patients in this series remained free of erosions after completion of stromal puncture, except for one woman with marked diffuse anterior basement membrane dystrophy, who went on to develop spontaneous bilateral erosions. Follow-up ranged from 2 months to 30 months (mean, 13 months). There were no complications of stromal puncture, and subjective and objective evaluations revealed no significant postoperative glare. Microscopic analysis of eye bank eyes subjected to anterior stromal puncture procedures demonstrated that the new prototype needle provided shallower penetration and thus less likelihood of perforation or excessive scarring than the straight needle. Also, postoperative discomfort and scarring appeared to be significantly less in patients treated with the prototype needle.

Diphtheroids as ocular pathogens.

Unlike Corynebacterium diphtheriae and Propionibacterium acnes, the pleomorphic gram-positive rods known as diphtheroids are generally regarded as nonpathogenic contaminants of the human external eye. We reviewed five years of microbiology records at Wills Eye Hospital and studied a series of eight cases of apparently infectious keratitis associated with heavy growth of diphtheroids on cultures of ulcer scrapings. All of these cases included indolent ulcers that occurred almost exclusively in elderly patients (mean age, 72 years; range, 11 to 92 years). All patients had preexisting ocular conditions that compromised the corneal surface such as exposed corneal sutures, eyelid surgery, aphakic extended wear contact lenses, viral keratitis, and diabetes mellitus. No other pathogens were isolated. All infections responded well to antibiotic therapy with all organisms sensitive to cefazolin and all but one sensitive to gentamicin.