ANALYSIS OF CORNEAL ASPHERICITY (Q VALUE) AND ITS RELATED FACTORS: A STUDY IN KARACHI, PAKISTAN

Rayyan Zakir; Nauman Hashmani; Muhammad Usman Jamil; Nasr Zeyad; Javeria Saleem; Rida Ayub; Sharif Hashmani; Muhammad Maaz Arif

ANALYSIS OF CORNEAL ASPHERICITY (Q VALUE) AND ITS RELATED FACTORS: A STUDY IN KARACHI, PAKISTAN

Rayyan Zakir, Nauman Hashmani, Muhammad Usman Jamil, Nasr Zeyad, Javeria Saleem, Rida Ayub, Sharif Hashmani, Muhammad Maaz Arif

Abstract

Objective: The aim of this study was to analyze corneal Q value and its relationship with associated factors.

Design: It was a cross-sectional study.

Patients and methods: A total of 619 left eye patients from Hashmanis Group of Hospitals, Karachi were included. Through slit-lamp bio-microscopy examination and topographic data using Pentacam scans was obtained. Participants were categorized into age groups of 18–29 years, 30–44 years, and 45–59 years. Statistical analysis included Spearman’s rank correlation, Independent sample test, and ANOVA utilizing SPSS V.25. A significance level of p≤0.05 was considered to indicate statistical significance.

Results: Among the 619 patients, 219 (35.4%) were males and 400 (64.6%) were females. The mean age of patients was 35.4±7.6 years. The mean Q-value of the anterior (front) surface of the cornea was -0.400±0.117 mm and the mean Q-value of the posterior (back) surface was -0.384±0.125 mm.

Conclusion: Most of the corneas exhibited a prolate shape, indicating a more elongated structure in the anterior-posterior axis. The analysis revealed that asphericity of the posterior cornea showed a significant positive association with gender. However, the study did not find a significant relationship between posterior corneal asphericity and age, implying that age may not be a determining factor in corneal morphology. To strengthen the validity of these initial observations, further investigations with larger sample sizes and diverse populations are required.

Keywords

Ophthalmology; Cornea; Ocular refraction; Hospitals; Pakistan

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