Abstract
Purpose :
APDs are a condition when there is an unequal response to a light stimulus, indicating unequal optic nerve / retinal disease. Health care providers screen for APD by performing a swinging flashlight test (SL test). However, SL test can be difficult to execute causing inter-observer variability and quantification of APD, from the author’s experience, is seldom done. QP may solve shortcomings of SL test by objectively quantifying pupil responses to a light stimulus, and may have better sensitivity.
Methods :
Retrospective review of 456 patients presenting for pre-surgical evaluation in a two physician cataract and refractive practice. Patients over 18 years of age without iris / pupil damage had QP via the EyeKinetix II (Konan Medical) in a room at 35 lux. Values over 0.5 on the Eyekinetix RAPD score (ERS) were considered indicative of an APD. (Note: Konan uses ERS of 0.3 for possible APD; we chose 0.5 based on instrument reproducibility tests). A subset of APD patients were referred out for additional workup with their consult letters read for documented APD.
Results :
Of 456 patients, 56 had ERS above 0.5. Attributed causes: glaucoma (28), retinal detachment (5), NAION (3), Thyroid Eye Disease (2), ARMD (2), workup pending (8) and other (8) including CRAO, pituitary tumors, and multiple sclerosis. Of 36 patients referred, 4 had APD detectable by sub-specialists (smallest ERS by sub-specialist was 0.91). Subsequent workup showed all patients had abnormal visual fields, and/or clinically significant thinning of retinal nerve fiber layer and/or ganglion cell layer. Insufficient ERS threshold was observed in 3 patients with pseudotumor, 2 with strokes, and 1 with papilledema.
Conclusions :
QP appears to be an indispensable tool for screening patients. While bilateral diseases may not trigger APD, elevated ERS values are strong indicators further workup is needed. QP appears more sensitive to APD detection vs health care provider SL test. Quantification of APDs by QP makes QP a useful adjunct in clinical decision-making processes for further testing (e.g. OCT, Visual Field, etc) and may make QP suitable for progression monitoring. Additional research is needed to study further benefits of QP amongst different patient populations as well as longitudinal evaluations.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.