Duret Brainstem Hemorrhage After Transtentorial Descending Brain Herniation: A Systematic Review and Meta-Analysis

Historically, the occurrence of hemorrhage in the brainstem after an episode of supratentorial intracranial hypertension was described by Henri Duret in 1878. Nevertheless, to date the eponym Duret brainstem hemorrhage (DBH) lacks systematic evidence regarding its epidemiology, pathophysiology, clinical and radiologic presentation, and outcome. We conducted a systematic literature review and meta-analysis using the Medline database from inception to 2022 looking for English-language articles concerning DBH, in accordance with the PRISMA guidelines. The research yielded 28 articles for 32 patients (mean age, 50 years; male/female ratio, 3:1). Of patients, 41% had head trauma causing 63% of subdural hematoma, responsible for coma in 78% and mydriasis in 69%. DBH appeared on the emergency imaging in 41% and on delayed imaging in 56%. DBH was located in the midbrain in 41% of the patients, and in the upper middle pons in 56%. DBH was caused by sudden downward displacement of the upper brainstem secondary to supratentorial intracranial hypertension (91%), intracranial hypotension (6%), or mechanical traction (3%). Such downward displacement caused the rupture of basilar artery perforators. Brainstem focal symptoms (P = 0.003) and decompressive craniectomy (P = 0.164) were potential favorable prognostic factors, whereas an age >50 years showed a trend toward a poor prognosis (P = 0.0731). Unlike its historical description, DBH appears as a focal hematoma in the upper brainstem caused by the rupture of anteromedial basilar artery perforators after sudden downward displacement of the brainstem, regardless of its cause.