Contrast Sensitivity Function: A More Sensitive Index for Assessing Protective Effects of the Cilioretinal Artery on Macular Function in High Myopia

PURPOSE: To assess the benefits of the cilioretinal artery on macular function in high myopia using the quantitative contrast sensitivity function (qCSF) method. METHODS: This cross-sectional study was conducted at the Eye and Ear, Nose, and Throat Hospital of Fudan University. In total, 137 highly myopic patients (with axial length [AL] ≥ 26.00 mm) were enrolled and divided into cilioretinal artery absent and present groups based on their fundus photographs. One eye in each patient was randomly selected. Choroid thickness was measured using macular optical coherence tomography. The best-corrected visual acuity (BCVA) was evaluated by Early Treatment Diabetic Retinopathy Study charts, and the area under the log CSF (AULCSF), CSF acuity, and CS at six spatial frequencies were evaluated with the qCSF method. RESULTS: Although no significant BCVA difference was found between the cilioretinal artery absent (97 patients) and present (40 patients) groups, choroid thickness, AULCSF, CSF acuity, and CSF at low and intermediate spatial frequencies (1–6 cycles per degree) were all significantly higher in the cilioretinal artery present group than in the absent group (all P < 0.05). In addition, eyes with temporal cilioretinal arteries exhibited significantly higher AULCSF, CSF acuity, and CSFs at 3 and 6 cycles per degree (all P < 0.05) than those with a nasal one (all P < 0.05). Multivariate analysis showed that better AULCSF was associated with the presence of cilioretinal artery and the interaction of AL and choroid thickness. CONCLUSIONS: The cilioretinal artery may associate with the larger choroid thickness in highly myopic eyes and may play a role in preserving qCSF outcomes, which are more sensitive than chart-based acuity tests.