Comparison of CSV-۱۰۰۰ and Metrovision contrast sensitivity tests in normal eyes

Abstract Background: Measuring contrast sensitivity (CS) allows a better understanding of the visual performance of the human eye. This study aimed to examine the correlation and agreement between the results of two sinewave grating-based CS measurement methods, Metrovision and CSV-۱۰۰۰, in normal eyes. Methods: This cross-sectional, comparative study was performed between December ۲۰۱۸ and April ۲۰۱۹, at an optometry clinic. Subjects underwent comprehensive ocular examinations, which included pupil reflexes, subjective refraction, external eye examinations, smooth pursuit eye movement assessment, the cover–uncover test, and detailed slit-lamp examination of the anterior and posterior segments. Metrovision and CSV-۱۰۰۰ were employed to assess CS under photopic conditions. The correlation and agreement of the results of the two tests were evaluated. Results: CS was measured for ۱۰۴ normal eyes for ۳, ۶, ۱۲, and ۱۸ cycles per degree (cpd) spatial frequencies (participants’ mean age ± standard deviation: ۳۷.۳ ± ۲۶.۴ years). The CSV-۱۰۰۰ measurements were significantly higher for the ۳ and ۶ cpd spatial frequencies (both P = ۰.۰۱); however, at higher spatial frequencies, CS scores were similar. The highest and lowest differences between the two tests were recorded for the ۳ cpd spatial frequency and ۱۸ cpd spatial frequency, respectively. Except for the ۳ cpd spatial frequency, in both eyes, the findings correlated significantly between the CSV-۱۰۰۰ and Metrovision (P < ۰.۰۵). The narrowest and widest limits of agreement between the two tests were found for the ۱۲ and ۳ cpd spatial frequencies, respectively. Conclusions: The CSV-۱۰۰۰ method estimated CS higher than the Metrovision method, mostly at lower spatial frequencies. Furthermore, the agreement between the two methods was greater at higher spatial frequencies than at lower frequencies. This should be kept in mind when using the two methods interchangeably in visual screening. Keywords: contrast sensitivity spatial frequencies correlation agreement limit of agreement Metrovision CSV-۱۰۰۰ Bland?Altman analysis Spearman rank correlation normal eye