Real-world simulation of an alternative retinopathy of prematurity screening system in Thailand: A pilot study

Abstract

Purpose: To evaluate an alternative retinopathy of prematurity (ROP) screening system that identifies infants meriting examination by an ophthalmologist in a middleincome country. Methods: The authors hypothesized that grading posterior pole images for the presence of pre-plus or plus disease has high sensitivity to identify infants with type 1 ROP that requires treatment. Part 1 of the study evaluated the feasibility of having a non-ophthalmologist health care worker obtain retinal images of prematurely born infants using a non-contact retinal camera (Pictor; Volk Optical, Inc., Mentor, OH) that were of sufficient quality to grade for pre-plus or plus disease. Part 2 investigated the accuracy of grading these images to identify infants with type 1 ROP. The authors prospectively recruited infants at Chulalongkorn University Hospital (Bangkok, Thailand). On days infants underwent routine ROP screening, a trained health care worker imaged their retinas with Pictor. Two ROP experts graded these serial images from a remote location for image gradability and posterior pole disease. Results: Fifty-six infants were included. Overall, 69.4% of infant imaging sessions were gradable. Among gradable images, the sensitivity of both graders for identifying an infant with type 1 ROP by grading for the presence of pre-plus or plus disease was 1.0 (95% confidence interval [CI]: 0.31 to 1.0) for grader 1 and 1.0 (95% CI: 0.40 to 1.0) for grader 2. The specificity was 0.93 (95% CI: 0.76 to 0.99) for grader 1 and 0.74 (95% CI: 0.53 to 0.88) for grader 2. Conclusions: It was feasible for a trained non-ophthalmologist health care worker to obtain retinal images of infants using the Pictor that were of sufficient quality to identify infants with type 1 ROP.