Comparative postoperative topography pattern recognition analysis using axial vs tangential curvature maps.

PURPOSE: To determine prediction accuracy of patient refractive surgery status by novice reviewers based on topography pattern analysis using axial or tangential anterior curvature maps. SETTING: Four U.S. academic centers. DESIGN: Prospective case-control study. METHODS: Image evaluation was performed by novice reviewers (n = 52) at 4 academic institutions. Participants were shown 60 total images from 30 eyes presenting for cataract surgery evaluation with known refractive surgery status, including 12 eyes imaged with Placido-based topography and 18 eyes imaged with Scheimpflug-based tomography. There were 12 eyes with myopic ablations, 12 eyes with hyperopic ablations, and 6 eyes with no previous refractive surgery performed. Each eye was shown in both axial and tangential curvature from either device, reviewed as a single image at a time, and masked to the map type (axial vs tangential). RESULTS: For the 52 novice reviewers included, accuracy of pattern identification was 82.9% (517 of 624) for tangential vs 55.0% (343 of 624) for axial maps for eyes with myopic ablation (P < .00001), 90.9% (567 of 624) for tangential vs 58.3% (364 of 624) for axial maps for eyes with hyperopic ablation (P < .00001), and 15.4% (48 of 312) for tangential vs 62.8% (196 of 312) for axial maps for eyes with no ablation (P < .00001). There were no significant differences between Placido and Scheimpflug devices and no significant differences across groups based on year of training. CONCLUSIONS: Tangential curvature maps yielded significantly better pattern recognition accuracy compared with axial maps after myopic and hyperopic corneal refractive surgery ablations for novice reviewers. Using tangential curvature maps, especially for challenging cases, should benefit post-LASIK intraocular lens (IOL) calculator selection and, thereby, improve IOL power calculation accuracy.

"Eye Dropping"-A Case Report of Transconjunctival Lysergic Acid Diethylamide Drug Abuse.

PURPOSE: To report a case of bilateral toxic corneal and conjunctival epitheliopathy secondary to administration of filter paper impregnated with lysergic acid diethylamide (LSD) in the inferior conjunctival fornices. METHODS: This is a single case report of an 18-year-old man who presented to the emergency department with acute, bilateral eye pain and redness of 24 hours. The patient admitted to placing folded strips of blotting paper impregnated with LSD into the inferior fornices of his eyes the previous night. RESULTS: The patient was found to have localized bilateral corneal and conjunctival abrasions with underlying subconjunctival hemorrhage. Conjunctival abrasion was "kissing," involving the bulbar and palpebral conjunctiva, corresponding to the presumed location of the filter paper. There was no corneal stromal opacification. He was lost to follow up within 1 week of initial presentation but stated that his symptoms improved. CONCLUSIONS: To the best of our knowledge, this is the first reported case of bilateral hemorrhagic conjunctival abrasion and corneal abrasion secondary to LSD. "Kissing" conjunctival lesions, which have been previously reported with heroin use, should raise suspicion for drug abuse.

Epithelial remodeling after corneal crosslinking using higher fluence and accelerated treatment time.

PURPOSE: To evaluate changes in regional corneal epithelial thickness after corneal crosslinking (CXL) using higher fluence (7.2 J/cm2) and accelerated treatment time (4 minutes) in eyes with progressive keratoconus using spectral-domain optical coherence tomography (SD-OCT) and to correlate focal epithelial and focal anterior curvature changes. SETTING: Academic medical center in the United States. DESIGN: Prospective case series. METHODS: Patients had anterior segment SD-OCT (RTVue-100) with focal stromal and epithelial measurements and Scheimpflug imaging before and 1, 3, 6, and 12 months after accelerated CXL. RESULTS: Twenty-seven eyes from 20 patients were evaluated. Before the accelerated CXL, the epithelium was thinnest in the inferior inner and outer temporal regions, whereas at 12 months postoperatively, the epithelium was significantly thinned in multiple inferior and nasal regions by 1.1 to 3.2 µm (P < .05, all measurements), with no significant changes from 6 to 12 months. Epithelial thickness standard deviation across the central 6.0 mm was significantly reduced by 3 months (1.4 µm, P = .09) and remained stable at 12 months (P = .009). Change in epithelial thickness was poorly correlated to change in anterior curvature (r = -0.035). CONCLUSIONS: Significant epithelial remodeling occurred after accelerated CXL in eyes with progressive keratoconus, with improved regularity across the central 6.0 mm, by 6 months after treatment. There was poor correlation between focal epithelial thickness and anterior curvature changes, with wide variability between patients. Establishing the pattern of epithelial remodeling after CXL might help optimize future custom treatment protocols.

Limbal Cysts: A Subset Exhibiting Cornea-Specific Cytokeratins.

Two cases of limbal cysts lined by nonkeratinizing epithelium were studied with a panel of cytokeratins. One was a long-standing lesion in a 30-year-old man, whereas the other was excised from a 40-year-old man following pterygium surgery. Each cyst was immunostained with a panel of cytokeratins that were specific exclusively and separately for corneal and conjunctival epithelia. The epithelial lining of each cyst was CK12 positive for corneal epithelium and CK13 negative for conjunctival epithelium. It is hypothesized that a subset of corneoscleral cysts contain corneal epithelium, probably derived from a type of limbal stem cell differentiation.

Combination therapy accelerates diabetic wound closure.

BACKGROUND: Non-healing foot ulcers are the most common cause of non-traumatic amputation and hospitalization amongst diabetics in the developed world. Impaired wound neovascularization perpetuates a cycle of dysfunctional tissue repair and regeneration. Evidence implicates defective mobilization of marrow-derived progenitor cells (PCs) as a fundamental cause of impaired diabetic neovascularization. Currently, there are no FDA-approved therapies to address this defect. Here we report an endogenous PC strategy to improve diabetic wound neovascularization and closure through a combination therapy of AMD3100, which mobilizes marrow-derived PCs by competitively binding to the cell surface CXCR4 receptor, and PDGF-BB, which is a protein known to enhance cell growth, progenitor cell migration and angiogenesis. METHODS AND RESULTS: Wounded mice were assigned to 1 of 5 experimental arms (n = 8/arm): saline treated wild-type, saline treated diabetic, AMD3100 treated diabetic, PDGF-BB treated diabetic, and AMD3100/PDGF-BB treated diabetic. Circulating PC number and wound vascularity were analyzed for each group (n = 8/group). Cellular function was assessed in the presence of AMD3100. Using a validated preclinical model of type II diabetic wound healing, we show that AMD3100 therapy (10 mg/kg; i.p. daily) alone can rescue diabetes-specific defects in PC mobilization, but cannot restore normal wound neovascularization. Through further investigation, we demonstrate an acquired trafficking-defect within AMD3100-treated diabetic PCs that can be rescued by PDGF-BB (2 µg; topical) supplementation within the wound environment. Finally, we determine that combination therapy restores diabetic wound neovascularization and accelerates time to wound closure by 40%. CONCLUSIONS: Combination AMD3100 and PDGF-BB therapy synergistically improves BM PC mobilization and trafficking, resulting in significantly improved diabetic wound closure and neovascularization. The success of this endogenous, cell-based strategy to improve diabetic wound healing using FDA-approved therapies is inherently translatable.

Spectral-domain optical coherence tomography as a screening technique for chloroquine and hydroxychloroquine retinal toxicity.

BACKGROUND AND OBJECTIVE: To determine the effectiveness of spectral-domain optical coherence tomography (SD-OCT) as a screening tool for the evaluation of chloroquine or hydroxychloroquine retinal toxicity. PATIENTS AND METHODS: This is a prospective, case-control study. Subject eyes were divided into four groups (group I = eyes with bull's eye maculopathy, group II = eyes with early changes of toxicity, group III = eyes with exposure but no signs of toxicity, and group IV = eyes of age-matched controls). Retinal thickness was measured via SD-OCT 0.5 and 1.0 mm from the foveal center. RESULTS: Mean retinal thickness 1.0 mm from the fovea in group I eyes was significantly thinner when compared to group IV. Eyes in group II also showed retinal thinning 1.0 mm from the foveal center when compared to both groups III and IV. Mean retinal thickness 0.5 mm from the foveal center did not differ significantly between any groups. CONCLUSION: Significant retinal thinning occurred 1.0 mm, but not 0.5 mm, from the foveal center in patients with early and late chloroquine or hydroxychloroquine toxicity. Measuring retinal thickness 1.0 mm from the foveal center in patients receiving these medications may help screen for early toxicity.