Evaluation of Fungal Keratitis using a Newly Developed Computer Program, Optscore, for Grading Digital Corneal Photographs

Abstract

Purpose To validate computer software developed to assess digital corneal photographs of fungal keratitis in clinical research. Methods A cornea specialist and five medical students (after training) graded on two occasions 100 corneal photographs of patients with fungal keratitis using Optscore software. Variables assessed were lesion area, location, degree of opacity, percentage of the ulcer lying within a central 4mm circle of the cornea. Intraclass correlation coefficients (ICCs) were used to assess intragrader reliability, agreement of the students with the corneal specialist, and the reliability of the group mean of the student raters. The area determined using Optscore was compared to the area estimated from slit lamp and to visual acuity. Results As a group, medical students achieved an ICC greater than 0.9 for five out of the seven assessed variables. Similar levels of consistency were found after analyzing the graders’ individual results compared to the specialist. The area estimated using slit lamp examination was highly correlated with the mean area determined by Optscore, as was the logarithm of the minimum angle of resolution visual acuity at enrollment. Conclusions Non-expert graders using Optscore to assess digital photographs of fungal keratitis are self-consistent, agree with an expert grader both as a group and individually, and measurements of ulcer area obtained from Optscore are highly correlated with measurements of the same patients obtained on clinical examination. These observations support the validity of Optscore for assessing corneal pathology associated with fungal keratitis and make it a promising clinical research tool.

The impact of the COVID-19 pandemic on microbial keratitis presentation patterns

“…In this study, presenting VA, ulcer area, CIS, and final VA were utilised as proxy measures of severity. This represents an inherent limitation within the study; although severity scales for MK have been proposed [ 34 , 35 ], there is currently no widely accepted severity stratification system that adequately covers the entire spectrum of the disease. Complications and interventions are indicators of severity; however, these relatively rare events occurred too infrequently to offer insight here.…”

Novel Image-Based Analysis for Reduction of Clinician-Dependent Variability in Measurement of the Corneal Ulcer Size

“…20 More recently, Toutain-Kidd et al described an easy to use, online, computer software to assess digital corneal photographs of fungal keratitis. 21 In that study, both ophthalmologists and non-ophthalmologists (medical students) manually traced the boundaries of the stromal infiltrate from digital photograph and achieved very good agreement in clinically relevant variables, such as area of infiltrate and proximity to the visual axis. We propose a semi-automated quantitative corneal measurement (QCM) method for segmentation and measurements of corneal ulcer from external photographs.…”

Open-Source Automatic Biomarker Measurement on Slit-Lamp Photography to Estimate Visual Acuity in Microbial Keratitis

“…Image-based and computer-aided methods can reduce clinician-dependent variability and improve reliability of measurements. 19 , 20 Slit-lamp photography (SLP) is a low-cost technology universally available in eye clinics that provides high-resolution digital images of the eye. 21 Semiautomatic and fully automatic segmentation algorithms have been developed for SLP images of MK.…”