Microsurgery and radiosurgery for brainstem cavernomas: effective and complementary treatment options

Abstract

Objective: To evaluate treatment options for brainstem cavernous malformations (BSCMs) using the results from a center with long-standing experience in microsurgical resection and Gamma Knife radiosurgery (GKRS) treatment of BSCMs.

Methods: Study participants were 67 symptomatic patients with BSCMs who were treated either microsurgically (n = 29) or radiosurgically (n = 38). Patients were followed for a minimum of 2 years (median, 7.7 years). A recent follow-up was performed.

Results: Patients receiving surgical treatment had mainly large, superficially seated lesions and experienced preoperative hemorrhages more often and presented with higher preoperative modified Rankin Scale scores. Patients receiving GKRS harbored smaller, deep-seated lesions, reflecting a selection bias. In both treatment groups, patients presented with significantly better modified Rankin Scale scores at follow-up than before intervention. Overall annual preoperative hemorrhage rates were 3.2% in microsurgery patients and 2.3% in radiosurgery patients. In the preoperative observation period, the rehemorrhage rate was 25.1% for microsurgery patients and 7.2% for radiosurgery patients. Hemorrhage rate after GKRS decreased significantly to 0.6% after 2 years. The postoperative hemorrhage rate was 8.8% but only for microsurgery patients with residual lesions. Advancements in microsurgical techniques improved surgical outcomes, resulting in a high total excision rate in the modern era.

Conclusions: In the treatment of BSCM, patient selection and timing of surgery are crucial. If applied in a multidisciplinary neurosurgical center, microsurgery and radiosurgery are complementary treatment options that both result in reduced bleeding rates and improvement of clinical outcome.

Keywords: Brainstem cavernous malformations; Hemorrhage; Microsurgery; Radiosurgery.