METHODS: This was a prospective cross-sectional study. All subjects underwent a full ophthalmic examination, refraction, visual field analysis and A-scan biometry. Myopic patients were classified as low myopia (LM) [spherical equivalent (SE) from greater than -0.5 D, up to -3.0 D], moderate myopia (MM; SE greater than -3.0 D, up to -6.0 D) and high myopia (HM; SE greater than -6.0 D). The control group consisted of emmetropic (EM) patients (SE from +0.5 D to -0.5 D). A Zeiss Cirrus HD-OCT machine was used to measure the peripapillary RNFL thickness of both eyes of each subject. The mean peripapillary RNFL thickness between groups was compared using both analysis of variance and analysis of covariance.
RESULTS: A total of 403 eyes of 403 subjects were included in this study. The mean age was 31.48±10.23y. There were 180 (44.7%) eyes with EM, 124 (30.8%) with LM, 73 (18.1%) with MM and 26 (6.5%) with HM. All groups of myopia severity had a thinner average RNFL than the EM group, but after controlling for gender, age, and axial eye length, only the HM group differed significantly from the EM group (P=0.017). Likewise, the superior, inferior and nasal RNFL was thinner in all myopia groups compared to controls, but after controlling for confounders, only the inferior quadrant RNFL was significantly thinner in the HM group, when compared to the EM group (P=0.017).
CONCLUSION: The average and inferior quadrant RNFL is thinner in highly myopic eyes compared to emmetropic eyes. Refractive status must be taken into consideration when interpreting the OCT of myopic patients, as RNFL thickness varies with the degree of myopia.
PURPOSE: To determine OSD prevalence and dry eye severity among glaucoma patients at nine private clinics in Malaysia.
METHODS: This multicentre, cross-sectional observational study recruited glaucoma patients undergoing routine eye examinations, with IOP ≤21mmHg receiving anti-glaucoma eye drops. OSD was assessed through National Eye Institute (NEI) scoring, tear film break-up time (TBUT), hyperaemia grading, Schirmer's tests and questionnaires on symptom evaluation, OSD index and quality of life (QoL).
RESULTS: Our cohort (n = 406, mostly male, ethnically Chinese, mean 63.5 ± 11.5 years, mean IOP 15.34 ± 2.95mmHg) frequently used prostaglandin analogues or PGA/beta-blockers and had cornea total NEI scores of 3.64 ± 2.76, mostly with minimal (51.2%) or mild (40.4%) epitheliopathy. Mean TBUT was 6.59 ± 3.08s (25.0%) in patients with severe lipid deficiency dry eye (DE). Bulbar conjunctiva hyperemia (70.4%) and palpebral conjunctiva hyperemia (68.0%) were mild. Schirmer's test showed that most had tear deficiency (70.2%) with severe DE (38.9%). Questionnaires reported ocular symptoms in few patients, but 69.2% had DE symptoms (13.1% moderate/severe). While QoL was good, several patients had QoL and OSD index scores suggesting some adaptation to ocular symptoms and discomfort, with most patients being unconcerned (43-60%) by the occurrence of eye drop side effects (75.4%).
CONCLUSION: Normal-mild DE or OSD can be asymptomatic, and the symptoms are unlikely to bother most patients. However, as OSD severity varies in patients with glaucoma, it should be evaluated using questionnaires and clinical tests to ensure that subjectively asymptomatic individuals are not missed.