Surgical treatment of cavernous malformations involving medulla oblongata

Surgical treatment of cavernous malformations (CMs) involving medulla oblongata is more difficult than the CMs in other sites because of the surrounding vital structures. However, the distinctive features and treatment strategies have not been well illustrated. Therefore, we enrolled a total of 19 patients underwent surgical treatment of CMs involving medulla oblongata in our hospital from August 2008 to August 2014. The clinical features, surgical management and clinical outcome of these patients were retrospectively analyzed, while our institutional surgical indications, approaches and microsurgical techniques were discussed. In our study, gross total resection was achieved in 17 patients and subtotal resection in 2. Two patients underwent emergency surgeries due to severe and progressive neurological deficits. The postoperative new-onset or worsened neurological deficits occurred in 6 patients. After a mean follow-up of 45.8±22.2months, the neurological status was improved in 10 patients and remained stable in 7. The mean modified Rankin Scale (mRS) was 2.58±1.26 preoperatively, 3.11±0.99 postoperatively and 1.84±1.42 at the recent follow-up, respectively. During the follow-up period, no rehemorrhage and recurrence occurred, and the residual lesions remained stable. We recommended surgical resection of symptomatic CMs involving medulla oblongata via optimal approaches, feasible entry zones and meticulous microsurgical techniques in attempting to achieve safe resection and favorable outcome. The clinical features, surgical indications, timing and microsurgical techniques of this special entity should be distinctive from the brainstem cavernous malformations in other sites.