Axial ocular dimensions and corneal astigmatism: The Kuala Pilah Cluster Cataract Study

Abstract

Introduction: The Kuala Pilah Cluster Project involves Kuala Pilah Hospital as the lead hospital and the Jempol Hospital and Tampin Hospital as the district hospitals, serving as a single entity to provide ophthalmology services to the local population. Purpose: To evaluate the distribution of ocular biometric parameters and corneal astigmatism in patients presenting for cataract surgery within the Kuala Pilah Cluster Hospital System. Study design and methods: A cross-sectional study conducted on 273 consecutive patients presented for cataract surgery between January and June 2017. Ocular biometry measurements, including axial length (AXL), lens thickness (LT), and anterior chamber depth (ACD) of each right eye were measured using immersion A-scan ultrasound. Keratometric (K) readings were obtained via auto keratometer. Results: The mean values for AXL, ACD, and LT were 23.40 ± 0.90 mm, 3.17 ± 0.49 mm, and 4.45 ± 0.96 mm, respectively. The average K-reading was 44.40 ± 1.59 D, with a mean corneal astigmatism of 0.82 ± 0.62 D. In this population, the females have significantly shorter AXL and ACD, but steeper K compared to the males (P < 0.001). The local Malays have higher AXL and ACD values compared to the Chinese and Indians. A total of 35.5% patients exhibited a corneal astigmatism greater than 1 D. The magnitude of preoperative astigmatism positively correlated with age (P < 0.001). Conclusions: Ocular dimensions vary with gender and race in cataract patients from the Kuala Pilah cluster population. The probability of a patient requiring astigmatic correction increases with age. The average profile of ocular biometric data and corneal astigmatism may help local ophthalmologists to predict intraocular lens selections prior to cataract outreach projects.