Ocular biometry characteristics and corneal astigmatisms in cataract surgery candidates at a tertiary care center in North-East India

PURPOSE: The purpose of this study is to determine the ocular biometry characteristics and corneal astigmatisms using partial coherence laser interferometry in patients aged 40 years or above undergoing cataract surgery in a medical college in North-East India. METHODS: In a hospital-based cross-sectional study, ocular biometry characteristics such as axial length (AL), anterior chamber depth (ACD), white-to-white (WTW) diameter, corneal power (K), and corneal astigmatisms (D) of consecutive eligible cataract patients in a medical college in North-East India between January 2015 and December 2017 were determined using the intraocular lens (IOL) master. Height and weight were also measured. RESULTS: A cross-sectional study evaluated ocular biometry characteristics of 641 eyes in 641 eligible patients. The mean age was 64.04 ± 10.81 years. The mean AL, ACD, WTW, corneal power, IOL power, and body mass index (BMI) were 23.34 ± 1.12 mm, 3.12 ± 0.39 mm, 11.92 ± 0.54 mm, 44.41 ± 1.50 diopter (D), 20.53 ± 2.79 D, and 26.12 ± 4.32, respectively. Against-the-rule, with-the-rule, and oblique astigmatisms were 48.4%, 33.2%, and 18.4%, respectively. Corneal astigmatism of ≥1 D was found in 292 eyes (45.55%) and >1.5 D in 182 eyes (28.39%). AL had statistically significant correlation with ACD, WTW, K, IOL power, height and weight but not with age. By multivariate analysis, AL was found to be associated with ACD, WTW, K and IOL power (P ≤ 0.05). The mean AL was negatively correlated with the mean K (R-square 0.138). CONCLUSION: This study is likely to provide the initial normative data for ocular biometry values in Indian adults 40 years or above, because such data is lacking in Indians using the IOL master. This will also help ophthalmologists in planning and improving the quality of surgical outcomes in phacoemulsification and phacorefractive surgeries by choosing the appropriate IOL and incision location.