EC Ophthalmology

Background: Precise measurement of the radius of curvature [K (mm)] and axial length (AL) of the eye are vital for a good outcome of a cataract extraction surgery. Average values of these dimensions of the optical components depend on race, age and gender. Although there are a number of studies that describe these mean parameters in the Caucasian, Hispanic and Asian populations, there has been little attention to the African population.

Objectives: The aim of this study was to estimate the biometric parameters of patients who had cataract surgery at University of Gondar (UoG), Tertiary eye care and training centre from September 2019 to August 2020.

Materials and Methods: Hospital based cross sectional study was done on patients who visited UoG Tertiary Eye Care and Training Center for cataract extraction surgery. Righton retinomax K plus 3 autorefractor, (Hutama Medical, Indonesia) and Pac Scan 300A contact A scan ultrasound, (Sonomed Escalon, NY, USA) were used to measure K (mm) and AL and calculate intraocular lens (IOL) power, respectively. Data were collected using a structured questionnaire, then entered to SPSS version 25 statistical software and analyzed.

Result: A total of 838 eyes (433 right eyes and 405 left eyes) of 486 of patients were included in this study. The mean age was 62.5 ± 12.88 years. The mean K1 and K2 were 7.75 ± 0.38 mm and 7.48 ± 0.33 mm, respectively. The mean average of K1 and K2 (AVK) was 7.61 ± 0.33 mm. The mean AL measured was 23.06 ± 1.05 mm and the mean Intraocular Lens (IOL) power calculated was 21.12 ± 2.95 D. Significant difference in mean AVK and mean AL of the eye exists between male and female patients, p value = 0.000.

Conclusion: This study provides the mean values of radius of curvature of cornea, axial length of the eye and IOL power of patients who were about to undergo cataract extraction surgery at the study center. Male patients had steeper corneas and longer axial lengths than females. But age had a variable effect on both AVK and AL.

 Keywords: Ocular Biometry; Cataract Surgery; Anterior Chamber Depth (ACD); Axial Length (AL)

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