The prevalence and presentation patterns of microcystic macular oedema: a systematic review and meta-analysis of 2128 glaucomatous eyes

We conducted this research to determine the prevalence rate and presentation patterns with microcystic macular oedema (MMO) in glaucoma patients. The protocol was pre-registered on PROSPERO (CRD42022316367). PubMed, Scopus, Web of Science, EMBASE, ProQuest, EBSCOHost, CENTRAL, clinicaltrials.gov, and Google Scholar were searched for articles reporting MMO in glaucoma patients. The primary outcome was the prevalence of MMO, while secondary outcomes included the comparison between MMO and non-MMO in terms of patients’ characteristics (age, gender), glaucoma stage, and ocular parameters (axial length (AL), intraocular pressure, mean deviation, spherical equivalent). Data are reported as mean difference (MD) or log odds ratio (logOR) along with their corresponding 95% confidence intervals (CI) for continuous and dichotomous outcomes, respectively. The quality of included studies was assessed using the NIH tool, and the certainty of evidence was assessed using GRADE framework. Ten studies (2128 eyes) were included, revealing an overall prevalence rate of MMO of 8% (95%CI: 5–12%). When compared to non-MMO group, MMO was associated with lower age (MD = −5.91; 95%CI: −6.02: −5.20), greater risk of advanced glaucoma stage (LogOR=1.41; 95%CI: 0.72: 2.09), and lower mean deviation of the visual field (MD = −5.00; 95%CI: −7.01: −2.99). No significant difference was noted between both groups in terms of gender, axial length, or spherical equivalent. Three studies had good quality while seven had poor quality. MMO is a prevalent observation in glaucoma patients and is associated with patients’ age and stage of the disease. However, the certainty of evidence remains very low.