Abstract
BACKGROUND: Spinal dumbbell-shaped epidural cavernous malformation (CM) is a rare, hypervascular entity frequently misdiagnosed for other lesions, leading to unexpected intraoperative bleeding and suboptimal resection. Our study aims to elucidate the demographics, management strategy, and outcome of this vascular disease. METHODS: Retrospective review of patients seen in Beijing Tiantan Hospital with symptomatic dumbbell-shaped epidural CM from 2008 to 2013. All lesions were pathologically confirmed after resection. The clinical manifestations, radiographic features, and treatment modalities of these cases were analyzed. RESULTS: We included 9 consecutive patients. Average age was 58 ± 12 years (range: 34-79 years), with 66.7% male. Locations of the CMs were: thoracic (n = 7, 77.8%), cervical (n = 1, 11.1%), and cervicothoracic junction (n = 1, 11.1%). Only one case presented with acute manifestations while others experienced chronic progressive spinal cord symptoms. The initial clinical diagnoses were: schwannoma (n = 6, 66.7%), cavernous hemangioma (CM) (n = 1, 11.1%), meningioma (n = 1, 11.1%), and angioma (n = 1, 11.1%). Total resection was achieved in six patients (66.7%), and partial resection in the other three patients (33.3%). Average intraoperative blood loss was 400 ± 300 ml (range: 100-1000 ml). During an average follow-up of 71 ± 21 months (range: 29-94 months), excellent outcome was achieved in seven cases (77.8%), one partially improved (11.1%), and one deteriorated (11.1%). No patients experienced recurrence of symptoms. CONCLUSIONS: Spinal dumbbell-shaped epidural CM is a benign vascular malformation that should be differentiated from other dumbbell-shaped lesions. Accurate preoperative diagnose is challenging as no specific radiographic marker has been established. Total surgical resection should be recommended.