Socio Demographic Distribution of Ocular Axial Length in Port Harcourt, Nigeria

Aim: To determine the socio demographic distribution of ocular axial length (AL) for use in estimating intraocular lens power, detect abnormal values and possibly associate them with pathological conditions.

Methods: This is a community based descriptive study carried out in Port Harcourt City LGA, Nigeria of subjects 18 years of age or older and with Visual Acuity > 6/18. The major ethnic/linguistic groups in Rivers state are Ikwerre, Ogoni, Ekpeye Kalabari, Okrika, Ogba, Igbani, Obolo and Etche. Socio demographic data was obtained through a proforma. Ocular examinations done included visual acuity, applanation tonometry, and ophthalmoscopy. Axial length (AL) was measured using Amplitude (A) scan ultrasonography (SONOMED PACSCAN 300AP). Data analysis was by SPSS (Version 17), and p value was set at ≤ 0.05.

Results: Four hundred and sixty six (466) subjects participated in the study made up of two hundred and twelve (212) males (45.5%) and two hundred and fifty four (254) females (54.5%) with M: F ratio of 1:1.2. The age range was 18-92 years and mean age of the subjects studied 43.0±14.2 years. Findings revealed mean AL to be 23.2±1.0 mm which was greater in males than females. The longest mean AL in males was seen among age group 51 and 60 years and that for females was seen in age group 41 and 50 years after which in both gender there was noticed to be a decline in mean axial lengths. There was no statistically significant relationship between age and axial length. Axial length was found to be longer in subjects with higher level of education and this pattern was statistically significant.

Conclusion: AL was significantly longer in males and has a positive relationship with the level of education of the study population. The longest mean AL in males was seen among age group 51 and 60 years and that for females was seen in age group 41 and 50 years after which in both gender there was noticed to be a decline in mean axial lengths.