ABSTRACT
Purpose: The present study aimed to assess the changes in optic disc and peripapillary retinal nerve fiber layer (RNFL) parameters in myopic patients and its correlation with axial length (AL) and spherical equivalent (SE) using optical coherence tomography (OCT). Methods: This was a cross?sectional study carried out from August 2019 to September 2021 in the ophthalmology department of a tertiary care hospital in eastern India. Myopic patients in the age group of 20–40 years and SE between ? 0.5 to ? 10 Diopters (D) were included in the study. Patients were divided into two groups on the basis of degree of myopia and AL. Appropriate statistical analysis was done at the end of the study period. Results: The study included 307 eyes of 307 myopic patients. There were 181 females (58.96%) and 126 males (41.04%). The mean age of the patients enrolled for the study was 28.78 ± 5.76 years. Statistically significant difference (P < 0.001) was found between SE and AL in between the subgroups of A and B. With every 1 D increase in SE, the average peripapillary RNFL thickness decreased by 0.61 ? while with every 1 mm increase in AL, the average peripapillary RNFL thickness was found to reduce by 1.03 ?. Conclusion: Analysis of optic nerve head parameters and RNFL thickness by OCT for the diagnosis should be compared with a normative control group that has been matched for refractive error and AL instead of comparison with a normative database that has only been age matched.
ABSTRACT
Purpose: To assess the role of lens parameters in the detection and progression of primary angle-closure disease (PACD) by combining A-scan and A-scan optical coherence tomography (AS-OCT) parameters. Methods: A cross-sectional study was conducted in a tertiary health-care center in eastern India. A total of 91 study subjects including cases and controls were included in the study. The parameters studied were lens thickness (LT), lens axial factor (LAF), relative lens position (RLP), and lens vault (LV). Anterior chamber depth (ACD) and axial length (AL) were also analyzed using A-scan. Results: The LT was significantly more in all subtypes of PACD (from 4.24 ± 0.84 to 5.02 ± 0.18 mm) than in controls (4.04 ± 0.46 mm; P < 0.01). Similarly, LAF was significantly less among all subtypes of PACD compared to controls (P < 0.001). The RLP, calculated using the formula (ACD + 0.5 LT)/AL × 10, showed no significant difference (P > 0.05) between various study groups. The LV in acute angle-closure glaucoma (AcCG) patients was significantly higher compared to the control population (P < 0.01). Ocular parameters like ACD decreased, whereas LT and LAF increased from normal through primary angle closure (PAC) to primary angle-closure glaucoma (PACG). Logistic regression analysis found a significant association between a decrease in ACD and an increased risk of PACG (P-value was 0.0001) and an increase in LT and LAF with increased risk of PACG (P = 0.040 and P = 0.006, respectively). Conclusion: Inclusion of lens parameter assessment in the workup of a patient with PACD helps in detection and close monitoring of the progression from suspected to disease state.