Surgical Resection of Brainstem Cavernoma: A Systematic Review of the Literature

Introduction: Brainstem cavernomas present a unique challenge. While cavernomas are generally benign lesions, the critical location in the brainstem makes them very difficult to approach. The main treatment remains surgical resection, but is fraught with high risk of morbidity and mortality. In this paper, we present a systematic review and meta-analysis of published cases of treated brainstem cavernoma.

Methods: A review of the literature was conducted by gathering articles and textbook chapters from the Pubmed, Web of Science, Scopus, Cochrane DBSR, and Embase databases. These were queried using the terms “cavernoma,” “cavernous malformation,” “cavernous angioma,” “brainstem,” “surgery,” and their related terms. A full systematic review and meta-analysis was conducted using PRISMA guidelines.

Results: A total of 1,046 articles were found. After duplicate screening, title and abstract screening, and full-text review, 100 surgical series were selected. Across 100 series, data were available for 2,257 patients with brainstem cavernomas that were surgically treated. These patients had an average age of 38.19 years and a male:female ratio of 0.88. The majority of these lesions were located in the pons (57.6%), followed by the midbrain (25.7%) and the medulla (22.5%), with some lesions spanning multiple brainstem structures. Prior to surgery, 98% of these patients experienced one or more hemorrhagic events. Gross total resection was achieved in 92.8% of patients following initial surgery. Periprocedural complications occurred in 41.9% of patients, with common complications including infection (9.8%), tracheostomy/percutaneous endoscopic gastrotomy (11.8%), CSF leak (6%), hydrocephalus (4.7%), and ventilator dependence (5.4%). In 65 studies (1,944 patients), the reported the rate of postoperative cranial neuropathy was 67%. For the most part, it is unclear whether the neuropathy was transient or permanent. In regard to clinical follow-up, a total of 81 studies with 1,744 patients were reported over an average of follow-up time of 38 months weeks. At latest available follow-up, the neurological conditions compared with baseline had improved in 59.9%, remained stable in 27.7%, and worsened in 10.3%, with death attributable to the disease or procedure occurring in 1.6%.

Conclusion: Surgical treatment for brainstem cavernomas remains a reasonable treatment option. However, this procedure carries high risks and requires careful planning and patient selection.