A novel quick contrast sensitivity function test in Chinese adults with myopia and its related parameters

This study is to investigate the contrast sensitivity function (CSF) using the quick CSF (qCSF) test in Chinese adults with myopia.

This case series study included 320 myopic eyes of 160 patients (mean age 27.75 ± 5.99 years) who underwent a qCSF test for acuity, area under log CSF (AULCSF), and mean contrast sensitivity (CS) at 1.0, 1.5, 3.0, 6.0, 12.0, and 18.0 cycle per degree (cpd). Spherical equivalent, corrected-distant visual acuity (CDVA), and pupil size were recorded.

The spherical equivalent, CDVA (LogMAR), spherical refraction, cylindrical refraction, and the scotopic pupil size of the included eyes were - 6.30 ± 2.27 D (- 14.25 to - 0.88 D), 0 ± 0.02, - 5.74 ± 2.18 D, - 1.11 ± 0.86 D, and 6.77 ± 0.73 mm, respectively. The AULCSF and CSF acuity were 1.01 ± 0.21 and 18.45 ± 5.39 cpd, respectively. The mean CS (log units) at six different spatial frequencies were 1.25 ± 0.14, 1.29 ± 0.14, 1.25 ± 0.14, 0.98 ± 0.26, 0.45 ± 0.28, and 0.13 ± 0.17, respectively. A mixed effect model showed significant correlations between age and acuity, AULCSF, and CSF at 1.0, 12.0, and 18.0 cpd. Interocular CSF differences were correlated with the interocular difference of spherical equivalent, spherical refraction (at 1.0 cpd, 1.5 cpd), and cylindrical refraction (at 12.0 cpd, 18.0 cpd). The lower cylindrical refraction eye had higher CSF compared with the higher cylindrical refraction eye (0.48 ± 0.29 vs. 0.42 ± 0.27 at 12.0 cpd and 0.15 ± 0.19 vs. 0.12 ± 0.15 at 18.0 cpd).

The age-related decrease in contrast sensitivity is at low and high spatial frequencies. Higher-degree myopia may show a decrease in CSF acuity. Low astigmatism was noted to affect the contrast sensitivity significantly.