Ocular biometry parameters in mobile cataract surgery camp: a large-scale report from Nigeria

Background: Humanitarian missions and mobile camp surgeries have pivotal roles in cataract surgery in areas with limited resources. Ocular biometry is an important preoperative evaluation tool for cataract surgery candidates. Herein, we report the distributions of ocular biometric values among cataract surgery candidates in camp settings in southern Nigeria. Methods: In this cross-sectional study, we retrieved data from consecutive patients scheduled for cataract surgery. All patients underwent a full ophthalmic examination using a slit-lamp biomicroscope. Age, sex, and preoperative biometric values, including anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL), together with intraocular lens (IOL) power, were documented. Biometric values were obtained using A-mode ultrasonography. Results: Records of 567 patients with a mean (standard deviation) age of 66.0 (13.4) years revealed a male-to-female sex ratio of 1:1.24. Most participants were in the 66–70-year age group. Mean IOL power was significantly different between males and females (P < 0.001). However, the biometric values were comparable between sexes (all P > 0.05). There were significant differences in the mean IOL power (P < 0.001) and ACD (P < 0.05) between the age groups, indicating a decrease in ACD with age. However, the other biometric parameters were comparable between the age groups (all P > 0.05). ACD had a significant weak negative correlation with LT (r = - 0.16; P < 0.001) and IOL power (r = - 0.22; P < 0.001) and a positive correlation with AL (r = + 0.24; P < 0.001). LT had a significant weak negative correlation with VCD (r = - 0.16; P < 0.001) and a positive correlation with AL (r = + 0.09; P < 0.05). VCD had significant moderate positive and negative correlations with AL (r = + 0.39; P < 0.001) and IOL power (r = - 0.34; P < 0.001), respectively. AL had a significant strong negative correlation with IOL power (r = - 0.78; P < 0.001). Conclusions: This study presents the mean distributions of ocular biometric parameters among cataract surgery candidates in camp settings in southern Nigeria. Age and sex were important determinants of IOL power and should be considered when planning eye camp supplies. AL had a strong inverse correlation with IOL power. Further multicenter national studies are required to verify these preliminary findings.