The distribution of anterior chamber depth in a Tehran population: the Tehran eye study

Abstract Purpose: To determine the normal range of anterior chamber depth (ACD) in the population of Tehran by age and gender. Materials and methods: Four hundred and ten people (800 eyes) aged 14 years and over, residing in the first four municipality areas of Tehran were selected through a stratified random cluster sampling method. The measurements were all taken by a single skilled technician using Orbscan II, between 9:00 am and 7:00 pm. The ACD was defined as the distance between the corneal endothelium and the anterior lens surface. Considering the high correlation between the ACD readings of contralateral eyes ( r = 0.82, p < 0.001), only data from right eyes were analysed. Results: In the participants, the mean age was 40.6 ± 16.8 years and 38.8% were male. The mean ACD was 2.79 mm [95% confidence interval (CI): 2.75–2.83]; 2.84 mm (95% CI: 2.79–2.90) in men and 2.75 mm (95% CI: 2.70–2.81) in women. Linear regression analysis revealed a mean ACD reduction of 0.013 mm per year of age ( p < 0.001). The ACD decreased by 0.056 mm per diopter of spherical equivalent and 0.018 mm per mmHg of IOP ( p < 0.001 and p = 0.030, respectively). Conclusions: We found the normal range of ACD in the population of Tehran which is slightly different from that reported from other geographical regions. The study also demonstrated the correlation of ACD with other factors; it decreases with age, and is slightly higher in men.