Ultrasonographic Evaluation of Optic Nerve Sheath Diameter among Healthy Chinese Adults.

The aim of the work described here was to establish the range for optic nerve sheath diameter (ONSD) and potential factors influencing ONSD in healthy Chinese adults. Both ONSDs were measured twice in the sagittal and transversal planes by two observers. The final ONSD value for each participant was the average of 16 measurements of both eyes. The ONSD range (N = 3680) among 230 participants was 2.65-4.30 mm. The upper ONSD limit was lower than those in previous studies in Caucasian and African samples. Simple linear regression analyses revealed that the ONSD was correlated with sex, body mass index and waistline and head circumference. After adjustment for potential confounds between these factors, sex (coefficient = 0.225, p < 0.001) and body mass index (coefficient = 0.042, p < 0.001) were independently associated with ONSD. Underweight women had the smallest ONSD. These results suggest that racial, sex, and body mass index differences should be noted when assessing ultrasonographic criteria.