Neurological and functional outcomes of 32 patients with hemorrhagic brainstem cavernous malformations: a practical guide for surgical planning

OBJECTIVE: Brainstem cavernous malformations (BSCMs) were once considered inoperable. Microsurgical resection now represents a valuable option for treating patients with hemorrhagic or symptomatic lesions. The aim of this study was to provide a practical guide for surgical planning by analyzing postoperative neurological and functional outcomes.

METHODS: The early- and long-term neurological (National Institutes of Health Stroke Scale [NIHSS] score) and functional (modified Rankin Scale [mRS] and Glasgow Outcome Scale [GOS] scores) outcomes of 32 patients who underwent surgery for hemorrhagic BSCM were reviewed. The three-step surgical planning was based on an anatomosurgical algorithm.

RESULTS: Nine lesions (28.1%) were located in the mesencephalon, 19 (59.4%) in the pons, and 4 (12.5%) in the medulla. A fronto-temporo-orbito-zygomatic approach was selected to reach anterior mesencephalic BSCMs (2, 6.3%). A retrosigmoid approach and its extended variant were selected for lateral mesencephalic (6, 18.8%), anterior (2, 6.3%) and lateral (13, 40.6%) pontine, and anterior (1, 3.1%) and lateral (1, 3.1%) medullary BSCMs. A supracerebellar infratentorial approach was selected for posterior mesencephalic BSCMs (1, 3.1%). A telovelar approach was selected for posterior pontine (4, 12.5%) and medullary (2, 6.3%) BSCMs. Total resection was achieved in 29 cases (90.6%), with a 12.5% rate of surgical complications. The NIHSS score progressively improved at both the early (5.16 ± 3.70 vs 4.63 ± 2.78, p = 0.446) and late (4.63 ± 2.78 vs 2.41 ± 2.39, p < 0.001) postoperative evaluations. Functional outcomes showed an initial deterioration followed by a long-term improvement (mRS score: 2.66 ± 1.07 vs 3.06 ± 1.11 vs 2.13 ± 1.29, GOS score: 3.78 ± 0.61 vs 3.59 ± 0.62 vs 4.19 ± 0.78). Time to surgery significantly correlated with early- and long-term NIHSS, mRS, and GOS scores, while the number of hemorrhages before surgery correlated with early- and long-term mRS and GOS scores.

CONCLUSIONS: Early surgery after the first bleed following systematic surgical planning may be considered as an effective option for managing hemorrhagic BSCMs with acceptable operative morbidity and relatively favorable early- and long-term neurological and functional outcomes.