Fostering evidence building for brainstem cavernous malformations: a critical appraisal of available evidence's quality through a systematic review and BSCM Reporting Guideline proposal.

Brainstem cavernous malformations (BSCMs) are clusters of dilated, thin-walled, sinusoidal vessels prone to hemorrhage, often leading to life-threatening neurological deficits. Despite their rarity, prompt intervention is frequently required. Advances in diagnostics and treatment, including microsurgery and stereotactic radiosurgery, have improved management, yet no clear consensus exists due to considerable variability and lack of standardization across studies. Inadequate reporting further limits the generation of high-quality evidence. This study aims to evaluate publishing rigor and propose a reporting guideline for BSCMs based on observed gaps. A systematic review was conducted following PRISMA guidelines, identifying studies from the past ten years in PubMed, Embase, and Web of Science. Studies were evaluated using EQUATOR-based criteria (STROBE, CONSORT) across seven domains: (1) patient baseline characteristics; (2) lesion characteristics; (3) definition of key concepts; (4) neurosurgeon/staff attributes; (5) anesthesia protocols; (6) procedural details; and (7) clinical outcomes and complications. Forty-two studies (3,566 patients) were included. Most consistently reported items were patient inclusion criteria (100%), radiosurgery procedural details (100%), surgical case identification (95.2%), and outcome definitions (93.3%). Less commonly reported were anesthesia protocols (2.4%), use of reporting guidelines (7.1%), surgeon experience (9.5%), patient comorbidities (11.9%), and definitions for radiosurgical lesion reduction (14.3%) or complication criteria (14.7%). Methodological and reporting shortcomings are prevalent in BSCM literature, undermining evidence synthesis. We propose a 58-item BSCM Reporting Guideline to address these deficiencies and improve study quality and comparability.