Chorioretinitis after keratitis caused by Acanthamoeba: case report and review of the literature.

OBJECTIVE: A clinicopathologic study to evaluate the histopathologic features associated with Acanthamoeba keratitis and chorioretinitis. DESIGN: Retrospective observational case report. METHODS: On the basis of the clinical history and histologic appearance, the enucleated eye and native corneal button were examined using hematoxylin-eosin stains and special periodic acid-Schiff and Gomori methenamine silver stains. RESULTS: Results of histologic examination of the cornea and retina showed numerous Acanthamoeba cysts in the cornea stromal layers, the necrotic retina, and preretinal and subretinal spaces. CONCLUSIONS: To the authors' knowledge, this is the first proven histologic case of ipsilateral chorioretinitis secondary to primary chronic keratitis caused by Acanthamoeba. The patient had a 30-month history of recurrent keratitis requiring four penetrating keratoplasties. We believe the chorioretinitis resulted from direct spread of the corneal amebic infection. The spread of the Acanthamoeba may have been facilitated by a combined keratoplasty, extracapsular cataract extraction, and intraocular lens insertion. In both specimens, the native corneal button and the enucleated eye with a corneal transplant, the general pathologists overlooked the presence of Acanthamoeba.

Infectious keratitis after laser refractive surgery.

PURPOSE: To report two cases of infectious keratitis, one fungal after photorefractive keratectomy (PRK) and the other bacterial after laser in situ keratomileusis (LASIK). DESIGN: Two interventional case reports. PARTICIPANTS: Case 1 is a male who was seen 3 weeks after PRK with a corneal ulceration. Case 2 involves a female who was seen 7 weeks after LASIK with interface granularity. RESULTS: Cultures in case 1 were identified as Scopulariopsis species, and despite intensive treatment, a therapeutic penetrating keratoplasty (PK) was eventually performed. Case 2 had cultures identified as Mycobacterium chelonae and also ultimately required a therapeutic PK. CONCLUSIONS: Two unusual infectious keratitides are reported after different laser refractive surgery techniques.

Topical mitomycin-C for subepithelial fibrosis after refractive corneal surgery.

OBJECTIVE: To determine the effectiveness of mitomycin-C (MMC), 0.02%, in preventing recurrence of corneal subepithelial fibrosis after debridement and/or keratectomy in patients who have undergone refractive corneal surgery. DESIGN: Noncomparative case series. PARTICIPANTS: Eight eyes of five patients with corneal subepithelial fibrosis who had previously undergone radial keratotomy (n = 4) or photorefractive keratectomy (n = 4). INTERVENTION: All eyes underwent epithelial debridement followed by a single intraoperative application of MMC (0.02%) for 2 minutes followed by saline irrigation. The eyes were then patched, or a bandage contact lens placed until epithelial healing was complete. MAIN OUTCOME MEASURES: Corneal clarity and best-corrected visual acuity (BCVA). RESULTS: In all cases, the cornea remained clear with no recurrence throughout the follow-up period (6-25 mos., mean, 13.8 mos). No adverse reactions were reported. BCVA improved in all cases. CONCLUSIONS: Subepithelial fibrosis can be a visually disabling condition after refractive corneal surgery. Topical application of MMC (0.02%) may be a successful method of preventing recurrence of subepithelial fibrosis after debridement.

Purse-string sutures for hyperopia following radial keratotomy.

BACKGROUND: Five years ago, we presented 19 procedures employing two intrastromal purse-string sutures to treat hyperopic shift following radial keratotomy. Thirty-four additional procedures and longer follow-up are now presented detailing the task of rehabilitating these eyes. METHODS: Fifty-three eyes of 53 radial keratotomy patients who were unhappy with their uncorrected vision and who were dissatisfied with contact lens or spectacle correction underwent double corneal intrastromal purse-string suturing and were subsequently followed for at least 1 year. There were seven eyes with primary overcorrection and 46 eyes with progressive hyperopic shift. Spherical equivalent refraction before purse-string sutures ranged from +0.50 to +6.25 D (mean, +2.60 D, SD +/- 1.26 D). Prior to purse-string suturing, uncorrected visual acuity ranged from 20/30 to 20/400 with 21 eyes (45.3%) 20/100 or worse. RESULTS: The follow-up after suturing averaged 3.6 years (range, 1 to 10 yr). All patients had follow-up of at least 1 year. The steepening in average keratometric power was 2.94 +/- 1.72 D (range, 1.06 to 6.68 D). The sherical equivalent refraction after suturing averaged -0.15 +/- 1.17 D (range, +3.75 to -2.50 D). Uncorrected visual acuity after suturing was 20/40 or better in 38 eyes (72%) and 20/50 to 20/100 in 15 eyes (28%). The number of eyes with a spherical equivalent refraction of +/- 0.50 D with 0.50 D or less refractive astigmatism was 15 (26% of eyes). There were 34 eyes (66%) with +/- 1.00 D with 1.00 D or less of refractive astigmatism, and 42 eyes (78%) with +/- 2.00 D with 2.00 D or less refractive astigmatism. Most of the spread was on the myopic side, as intended. There were no significant intraoperative or postoperative complications. Fifteen eyes gained two or more lines of best spectacle-corrected visual acuity and no eyes lost one line. CONCLUSION: Double intrastromal purse-string suturing produces steepening of the central cornea and reduces hyperopia after radial keratotomy.

Surgical correction of hyperopia following radial keratotomy.

BACKGROUND: No effective treatment for hyperopia following radial keratotomy has been described. A new surgical technique of two purse-string intrastromal sutures was investigated for correction of this hyperopia. METHODS: Eighteen radial keratotomy patients who were unhappy with uncorrected vision and who were unsatisfied with contact lens or spectacle correction, after informed consent, underwent corneal suturing. The 19 hyperopic eyes included 5 original overcorrections, 5 overcorrections after reoperation, and 9 progressive hyperopes. The refractive error ranged from +1.25 to +5.75 diopters spherical equivalent (mean +3.47 D). Presuturing uncorrected visual acuity ranged from 20/50 to 20/400 with 11 eyes (58%) 20/100 or worse. RESULTS: The follow up after double purse-string suturing averaged 24 months (range, 12 to 47 months). All patients had follow up of at least 1 year; 14 patients (74%) had follow up of 2 years or more. The change in refractive spherical equivalent following surgery averaged -3.30 D (range, -1.00 to -7.50 D). The steepening in average keratometry was 4.10 D (range, 1.00 to 8.00 D). The refraction after suturing averaged -1.12 D (range, +2.50 to -3.50 D). Uncorrected visual acuity after suturing was 20/40 or better in 14 eyes (74%), and 20/50 to 20/80 in 5 eyes (36%). There were no significant intraoperative, early or late postoperative complications. Seventeen eyes were either the same or gained 1 line of acuity; 2 eyes gained 2 lines of acuity; no eyes lost any lines of refractive Snellen acuity. CONCLUSIONS: The placement of two purse-string intrastromal sutures appears to provide significant steepening of the central cornea following excessive flattening after radial keratotomy. The steepening effect appears to remain stable with greater than 1-year follow up. This surgical technique offers an alternative to symptomatic hyperopic postradial keratotomy patients who cannot be corrected with spectacles or contact lenses.

Radial keratotomy in high myopia: an evaluation of one technique.

Ninety-one consecutive eyes of 53 patients with refractive errors of -6.00 to -11.50 diopters (D) spherical equivalent (mean, -7.48 D) underwent radial keratotomy with redeepening and astigmatic incisions. All eyes were examined at six months, and 65.9% had one year of follow-up (mean follow-up, 11.65 months). In retrospective analysis of this group, 78% of patients had greater than or equal to 20/40 uncorrected visual acuity at six months with 76% at one year. In 59.3% of patients they were with 1.0D of emmetropia at six months with 56.7% at one year. Overcorrections (greater than +1.00D) with 11.1% at six months and 13.3% at one year. Undercorrections (greater than -1.00D) were 29.6% at six months and 30% at one year. Four patients lost two lines of Snellen visual acuity.

Trauma after radial keratotomy.

Eight cases of trauma are reported in seven patients after radial keratotomy. Trauma occurred 2 weeks to 53 months postoperatively. There was mild, moderate, and severe trauma to the orbit and globe region in five patients and severe, direct trauma to the globe in three patients. The incisions remained intact in six cases. Two patients with severe, direct, ocular trauma opened a radial incision, had flat chambers, and were treated successfully with bandage lenses. In all eight instances of trauma, there was no permanent change from pre-trauma acuity (with or without correction).

Trephination of donor corneal buttons: a scanning electron microscopic study.

Corneal buttons were cut from cat and human donor eyes by anterior trephination (with or without scissor completion) and from excised corneoscleral rims by posterior trephination (with or without a press). Scanning electron microscopy was used to evaluate the slope and quality of the cut edge, the diameter of the section of Descemet's membrane that was actually cut, and the loss of endothelial cells around the cut edge. With anterior trephination, the diameter of the section of Descemet's membrane that is cut was found to be less than that of the trephine because the cut edge slopes inward. Posterior trephination with or without a press consistently produced circular buttons with accurately cut outward-sloping edges. This resulted in a diameter of Descemet's membrane which was greater than in the anteriorly trephinated buttons. There also was less damage to peripheral Descemet's membrane and endothelium with the posterior method, especially when compared to scissor cut buttons. A 360 degree peripheral ring of Descemet's membrnae (0.05 to 0.28 mm in width) was denuded of endothelial cells with all techniques.