Surgery of brainstem cavernous malformations: surgical nuances and outcomes of a monocentric series of 34 patients.

Background: Brainstem cavernous malformations (BCM) constitute one of the most controversial and challenging neurological pathologies: both natural course and surgical manipulation can lead to severe neurological symptoms by direct compression or following hemorrhage of this highly eloquent brain region.

Methods: The vascular section of the prospectively collected neurosurgical database of our center (2011-2023) was retrospectively reviewed, seeking all patients operated on for a sporadic BCM. Clinical, radiological and surgical data, operative records and videos were analyzed by independent reviewers with the assistance of a dedicated neuropsychologist, blinded to the hospital course.

Results: Thirty-four patients aged between 19 and 70 years were identified and considered for analyses, with different brainstem localizations. The clinical onset was hemorrhagic in almost all cases: the average mRS on admission was 2.47 (21 patients ≤ 2). Surgical treatment was performed on average 15.1 weeks after the last bleeding. At hospital discharge, the mean mRS was 3.26 (6 patients ≤ 2). After a mean follow-up of 56.59 weeks, 29 patients (85.3%) presented an improved or stable mRS compared to hospitalization and 5 had a slight worsening (14.7%).

Conclusion: Brainstem cavernoma is a rare entity with aggressive features due to the involved eloquence despite of the benign histology itself. Microsurgical resection should be tailored for each patient to the peculiar characteristics of the harbored lesion. Advanced planning techniques reduced morbidity; patients should be centralized in wide caseload hospitals with high specialization in neurovascular pathologies and should receive an appropriate counseling about natural history and risks of interventional treatment.