RAPDx Expanded Pupil Diagnostics: A new Dimension in Pupil Evaluation.

Introduction: Relative afferent pupillary defect (RAPD) is an imperative sign to assess the retinal and optic nerve function. However, RAPD is subjective, so leads to discrepancies and hence there is the need for a precise quantification of the same. Materials and Methods: 80 subjects were enrolled in the study, pupillary reactions were measured using RAPDx Expanded Pupil Diagnostics (Konan Medical USA, Inc., Irvine, CA, USA) and were compared with neutral density filter (NDF) (Gulden Ophthalmics) and swinging flashlight test. Results: The mean pupillary reactions assessed on NDF was less than 0.3 log units and that assessed on RAPDx was 0.28 log units (P<0.001 spearman’s coefficient). Conclusion: RAPDx is comparable to NDF and may be used as a screening tool in Ophthalmology clinic, and gives an accurate and precise quantification of pupillary responses.

Repeatability and Agreement of Four Biometers for Measuring Various Anterior Segment Parameters.

Purpose: To assess the repeatability and agreement of a new swept source optical coherence tomography (SS-OCT) biometer (IOL Master® 700, Carl Zeiss Meditec), an optical low coherence reflectometer (Lenstar LS 900®, Haag-Streit AG, Koeniz, Switzerland), a dual scheimpflug ray tracing biometer (Galilei G6®, Ziemer, Switzerland) and a partial coherence interferometer, AL scan® (Nidek Co. Ltd., Japan) to measure the keratometry (K), astigmatism (AST), axial length (AL), anterior chamber depth (ACD), central corneal thickness (CCT) and white-to-white (WTW) in cataractous eyes in a Cross-sectional study. Methods: 50 eyes of 50 consecutive patients scheduled for cataract surgery were included. Three consecutive scans were performed using the 4 biometers by a single operator. Within-subject standard deviation (Sw), test-retest repeatability and coefficient of variation for assessing repeatability were assessed. Bland-Altman plots for the agreement between the mean measurements of each machine were examined. Results: The mean age of patients was 60.2 ± 10.6 years. Dropouts for AL measurement were significantly higher in AL scan® and Galilei G6® compared to IOL Master® 700. There was good agreement between IOL Master® 700 and Lenstar LS 900® for AL and keratometry (P < 0.5). High variability was seen between the 4 machines for AST and WTW. Conclusion: The new SS-OCT biometer showed valid measurements, good repeatability and good agreement with the optical low coherence reflectometry biometer. The new long range SS-OCT biometer was better than the other three devices in acquiring AL measurements in denser cataracts due to better penetration.