Prevalence of cerebral visual impairment in developmental and Epileptic Encephalopathies: a systematic review protocol.

Background: Developmental and Epileptic Encephalopathies (DEEs) are defined by drug-resistant seizures and neurodevelopmental disorders. Over 50% of patients have a genetic cause. Studies have shown that patients with DEEs, regardless of genetic diagnosis, experience a central visual function disorder known as Cerebral (cortical) Visual Impairment (CVI). The prevalence of CVI in DEE patients is currently unknown. A quantitative synthesis of existing data on the prevalence rates of this condition would aid in understanding the magnitude of the problem, outlining future research, and suggesting the need for therapeutic strategies for early identification and prevention of the disorder.

Methods: The protocol followed the PRISMA-P statement for systematic review and meta-analysis protocols. The review will adhere to the JBI Manual for Evidence Synthesis (Systematic Reviews of Prevalence and Incidence) and use the CoCoPop framework to establish eligibility criteria. We will conduct a comprehensive search of several databases, including MEDLINE, EMBASE, Science Direct, Scopus, PsychINFO, Wiley, Highwire Press, and Cochrane Library of Systematic Reviews. Our primary focus will be determining the prevalence of cerebral visual impairments (Condition) in patients with developmental and epileptic encephalopathy (Population). To ensure clarity, we will provide a narrative summary of the risk of bias in the studies we include. The Cochrane Q statistic will be used to assess heterogeneity between studies. If the quantitative synthesis includes more than 10 studies, potential sources of heterogeneity will be investigated through subgroup and meta-regression analyses. Meta(bias)es analysis will also be performed. The quality of evidence for all outcomes will be evaluated using the Grading of Recommendations Assessment Development and Evaluation (GRADE) working group methodology.

Discussion: This protocol outlines a systematic review and meta-analysis to identify, collect, evaluate, and integrate epidemiological knowledge related to the prevalence of CVI in patients with DEEs. To the best of our knowledge, no other systematic review and meta-analysis has addressed this specific issue. The results will provide useful information for understanding the extent of the problem, outlining future research, and suggesting the need for early identification strategies.

Systematic review registrations: This Systematic Review Protocol was registered in PROSPERO (CRD42023448910).