PURPOSE: Previous studies have reported high right-left eye correlation in retinal vessel caliber. We test the hypothesis that right-left correlation in retinal vessel caliber would be reduced in anisometropic compared with emmetropic children. METHODS: Retinal arteriolar and venular calibers were measured in 12-year-old children. Three groups were selected: group 1, both eyes emmetropic (n = 214); group 2, right-left spherical equivalent refraction (SER) difference ≥1.00 but <2.00 diopter (D) (n = 35); and group 3, right-left SER difference ≥2.00 D (n = 32). Pearson's correlations between the two eyes were compared between group 1 and group 2 or 3. Associations between right-left difference in refractive error and right-left difference in caliber measurements were assessed using linear regression models. RESULTS: Right-left correlation in group 1 was 0.57 for central retinal arteriolar equivalent (CRAE) and 0.70 for central retinal venular equivalent (CRVE) compared with 0.60 and 0.82 for CRAE and CRVE, respectively, in group 2 (P = 0.42 and P = 0.08), and 0.36 and 0.52, respectively, in group 3 (P = 0.08 and P = 0.07, referenced to group 1). Each 1.00-D increase in right-left SER difference was associated with a 0.74-μm increase in mean CRAE difference (P = 0.02) and a 1.23-μm increase in mean CRVE difference between the two eyes (P = 0.002). Each 0.1-mm increase in right-left difference in axial length was associated with a 0.21-μm increase in the mean difference in CRAE (P = 0.01) and a 0.42-μm increase in the mean difference in CRVE (P < 0.0001) between the two eyes. CONCLUSIONS: Refractive error ≥2.00 D may contribute to variation in measurements of retinal vessel caliber.
PURPOSE: Previous studies have reported high right-left eye correlation in retinal vessel caliber. We test the hypothesis that right-left correlation in retinal vessel caliber would be reduced in anisometropic compared with emmetropic children. METHODS: Retinal arteriolar and venular calibers were measured in 12-year-old children. Three groups were selected: group 1, both eyes emmetropic (n = 214); group 2, right-left spherical equivalent refraction (SER) difference ≥1.00 but <2.00 diopter (D) (n = 35); and group 3, right-left SER difference ≥2.00 D (n = 32). Pearson's correlations between the two eyes were compared between group 1 and group 2 or 3. Associations between right-left difference in refractive error and right-left difference in caliber measurements were assessed using linear regression models. RESULTS: Right-left correlation in group 1 was 0.57 for central retinal arteriolar equivalent (CRAE) and 0.70 for central retinal venular equivalent (CRVE) compared with 0.60 and 0.82 for CRAE and CRVE, respectively, in group 2 (P = 0.42 and P = 0.08), and 0.36 and 0.52, respectively, in group 3 (P = 0.08 and P = 0.07, referenced to group 1). Each 1.00-D increase in right-left SER difference was associated with a 0.74-μm increase in mean CRAE difference (P = 0.02) and a 1.23-μm increase in mean CRVE difference between the two eyes (P = 0.002). Each 0.1-mm increase in right-left difference in axial length was associated with a 0.21-μm increase in the mean difference in CRAE (P = 0.01) and a 0.42-μm increase in the mean difference in CRVE (P < 0.0001) between the two eyes. CONCLUSIONS: Refractive error ≥2.00 D may contribute to variation in measurements of retinal vessel caliber.