Corneal cross-linking for Acanthamoeba keratitis in an orthokeratology patient after swimming in contaminated water.

PURPOSE: To report a case of Acanthamoeba keratitis diagnosed using confocal microscopy in a patient corrected by orthokeratology and treated with corneal crosslinking (CXL) after failure to respond to medical treatment. METHODS: After diagnosis, the patient was treated with several medications until CXL was applied during one 30-min session using ultraviolet A radiation and application of riboflavin. The clinical signs of the disease observed using slit-lamp biomicroscopy and confocal microscopy were evaluated and the visual acuity was measured during the course of the infection and treatment over a period of 30 months including 12 months of medical treatment, 9 months after cross-linking and amniotic membrane transplant and 9 months after penetrating keratoplasty and cataract extraction. RESULTS: In this case, confocal microscopy facilitated early diagnosis of an Acanthamoeba infection even if other signs and symptoms might be confounding. CXL was more effective than aggressive medication against the microorganism. After CXL, the symptoms and the corneal appearance improved significantly but the ulcer did not heal completely. After amniotic membrane transplantation, the patient underwent penetrating keratoplasty (PK) with no rejection, and the visual function substantially improved over 9 months of follow-up. CONCLUSIONS: Swimming in contaminated water might represent a risk for orthokeratology patients. CXL was effective for treating Acanthamoeba keratitis in an orthokeratology patient to eliminate active and cystic forms of the microorganism. Confocal microscopy was useful to confirm the diagnosis in the presence of confounding clinical signs observed during a conventional slit-lamp examination. Both CXL and confocal microscopy are essential to the outcome of PK.

Late-onset Candida keratitis after Descemet stripping automated endothelial keratoplasty: clinical and confocal microscopic report.

PURPOSE: To report clinical and confocal microscopy features of late-onset Candida albicans keratitis after Descemet stripping automated keratoplasty (DSAEK). METHODS: We performed clinical and confocal scan on a patient who underwent DSAEK and phacoemulsification for Fuchs endothelial dystrophy and cataract. RESULTS: A 76-year-old woman who underwent uneventful DSAEK and phacoemulsification presented with white to cream deposits 3 months after DSAEK. Confocal microscopy showed a hyperintense deposit at the lenticule and interface. Confocal scan also disclosed intense haze and inflammation at the interface and clusters of hyperreflective round structures resembling epithelial cells within the interface area. No signs of hyphae-like structures were seen. Late-onset symptoms misled us into a bacterial chronic endophthalmitis diagnosis, and the patient was started on topical and systemic antibiotics. Despite intense antibiotic therapy, the patient developed severe endophthalmitis, so we performed anterior vitrectomy and the donor lenticule was removed. Microbiology results from the removed lenticule showed infection by C albicans. Antifungal therapy with systemic and topical voriconazole controlled the infection. CONCLUSIONS: Candida interface keratitis is possible after DSAEK. The posterior location of infected tissue poses diagnostic and therapeutic challenges. In our case, the late onset of the symptoms and not performing corneoscleral rim cultures delayed correct diagnosis. This is the first reported case of post-DSAEK Candida keratitis with confocal microscopy images. A hyperintense granular deposit was seen at the lenticule and interface with confocal microscopy. We also observed intense haze, granular round structures resembling epithelial cells, and hyperreflective needle-shaped material at the interface. No hyphae-like structures were seen with confocal imaging.

Intraocular straylight and contrast sensitivity (1/2) and 6 months after laser in situ keratomileusis.

OBJECTIVES: To compare intraocular straylight and contrast sensitivity determined before and 15 days and 6 months after laser keratomileusis. METHODS: A single-centre, prospective, longitudinal randomized trial was performed on 20 subjects undergoing refractive surgery. In each subject, best spectacle-corrected visual acuity (BSCVA) and straylight and contrast sensitivity were determined preoperatively (on the day of refractive surgery) and then after laser in situ keratomileusis (LASIK) surgery in the 15-day and 6-month follow-up visits. Straylight was measured using the van den Berg straylight meter (third generation). Contrast sensitivity was determined under photopic and mesopic conditions using the VCTS 6500 (Vision Contrast Test System). BSCVA was measured using Early Treatment Diabetic Retinopathy Study charts (LogMAR units). All measurements were obtained over time and compared. RESULTS: Straylight values (mean +/- SD) were 0.99 +/- 0.03, 0.88 +/- 0.03, and 0.93 +/- 0.03 before and (1/2) and 6 months after LASIK surgery. These values significantly fell from preoperative levels to those recorded 15 days after LASIK (P = 0.03) although values at 6 months failed to differ from baseline (P>0.05). Photopic and mesopic contrast sensitivity measured at several spatial frequencies remained stable. No correlations between contrast sensitivity or BSCVA and intraocular straylight were observed 15 days and 6 months after LASIK. CONCLUSIONS: Intraocular straylight was reduced 15 days after surgery although by 6 months values returned to preoperative levels. These changes in straylight values could not be related to changes in mesopic and photopic contrast sensitivity or BSCVA during the follow-up period.