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Purpose Retroillumination photography analysis (RPA) is an objective tool for assessment of the number and distribution of guttae in eyes affected with Fuchs Corneal Dystrophy (FCD). Current protocols include manual processing of images; here we assess validity and interrater reliability of automated analysis across various levels of FCD severity. Methods Retroillumination photographs of 97 FCD-affected corneas were acquired and total counts of guttae previously summated manually. For each cornea, a single image was loaded into ImageJ software. We reduced color variability and subtracted background noise. Reflection of light from each gutta was identified as a local area of maximum intensity and counted automatically. Noise tolerance level was titrated for each cornea by examining a small region of each image with automated overlay to ensure appropriate coverage of individual guttae. We tested interrater reliability of automated counts of guttae across a spectrum of clinical and educational experience. Results A set of 97 retroillumination photographs were analyzed. Clinical severity as measured by a modified Krachmer scale ranged from a severity level of 1 to 5 in the set of analyzed corneas. Automated counts by an ophthalmologist correlated strongly with Krachmer grading (R2=0.79) and manual counts (R2=0.88). Intraclass correlation coefficient demonstrated strong correlation, at 0.924 (95% CI, 0.870- 0.958) among cases analyzed by three students, and 0.869 (95% CI, 0.797- 0.918) among cases for which images was analyzed by an ophthalmologist and two students. Conclusions Automated RPA allows for grading of FCD severity with high resolution across a spectrum of disease severity.

Purpose Retroillumination photography analysis (RPA) provides objective assessment of the number and distribution of guttae in Fuchs Corneal Dystrophy. Here, we assess its correlation with clinical grading using slit-lamp biomicroscopy across varying levels of severity. Methods Retroillumination photographs were conducted of 95 affected corneas with slit-lamp flash photography after pupillary dilation. Individual guttae were counted manually and the position of individual points recorded. Clinical grading using the Krachmer scale was documented for each eye during examination, and regression analyses were performed to identify the strength of association with number of guttae. We assessed range at each stage of clinical grading, and utilized the Mann-Whitney U test to assess whether clinical grading levels demonstrated successively higher numbers of guttae. Results Krachmer score ranged from 1 to 5, with mean of 2.6. Mean numbers of guttae at each level of severity were 289 (1+), 999 (2+), 2669 (3+), 5474 (4+), and 7133 (5+). Each stage demonstrated significantly higher numbers of guttae than its preceding level except from 4+ to 5+ (p=0.30), consistent with the definition of 4+ as the highest level defined by presence of guttae. Higher levels of clinical grading were associated with larger ranges of guttae (p<0.01). A linear regression model resulted in a strong fit between RPA and Krachmer score (r=0.81). Conclusion In this largest study of RPA data and comparison with subjective clinical grading of FCD severity, RPA correlates strongly and demonstrates enhanced definition of severity at advanced stages of disease.

Purpose:To determine whether prophylactic antibiotic use in patients with orbital fracture prevent orbital infection.Design:Retrospective cohort study.Participants:All patients diagnosed with orbital fracture between January 1, 2008 and March 1, 2014 at The George Washington University Hospital and Clinics.Main Outcome Measures:Development of orbital infection.Results:One hundred seventy-two patients with orbital fracture met our inclusion and exclusion criteria. No orbital infections were documented. Twenty subjects (12%) received no prophylactic antibiotic, and two (1%) received only one dose of antibiotics pre-operatively for surgery. For primary antibiotic, 136 subjects (79%) received oral antibiotics, and 14 (8%) received intravenous (IV) antibiotics (excluding cefazolin). Cephalexin and amoxicillin-clavulanate were the most prescribed oral antibiotics that are equally effective. Five-to-seven day courses of antibiotics had no increased infections compared to ten-to-fourteen day courses. Calculated boundaries for effectiveness of prophylactic antibiotics ranged from a Number Needed to Treat (NNT) of 75 to a Number Needed to Harm (NNH) of 198.Conclusion:Antibiotics for prevention of orbital infection in patients with orbital fractures have become widely used. Coordination between trauma teams and specialists is needed to prevent patient overmedication and antibiotic resistance. Should antibiotics be used, shorter courses and avoidance of broad spectrum agents are recommended. Additional studies are needed.