Evaluation of Normal Exophthalmometric Values in Iranian Population: A Systematic Review and Meta-Analysis

Normal level of eye protrusion is different in various populations and many factors such as age, sex, race, refractive error, and anthropometric characteristics affect it. There are limited studies in Iran about the normal amount of eye protrusion in healthy population and normal exophthalmometric values. In this meta-analysis, taking into account the results of the 4 studies, we decided to obtain a reference number in the normal Iranian population. The results of meta-analysis in 3 696 normal Iranian people showed that the average eye protrusion was 16.5 mm in men and 16.26 mm in women and there was no significant difference between two sexes (P=0.5). Also, in left and right eyes, this was 16.33 and 16.44 mm, respectively, which was not significant between two eyes (P=0.3). The mean exophthalmometric value was 17.10 in the Iranian population aged 13 to 19 and 16.32 in the population over 20 years, and the upper limit of exophthalmometry in the Iranian population was 20.15 mm, which is lower than in the western studies. It is essential to begin further evaluation of imaging and endocrine tests in the Iranian population when eye protrusion is over these standard values.