Dissecting Aneurysms on Vertebral Artery and its Branches / 대한뇌혈관외과학회지

BACKGROUND: Dissecting aneurysms of the vertebral artery are rare. Diagnosis and treatment of such condition aneurysm has a potentially higher degree of technical difficulty. The authors analyzed the clinical features and treatment modality for dissecting aneurysms arising from vertebral artery and its branches. METHODS: At the authors'institution between April. 2001 and Sep. 2004, 18 patients were diagnosed and treated for dissecting aneurysms of vertebral artery and its branches. The medical records and neuroimaging studies of the patients were reviewed retrospectively. RESULTS: 18 patients were comprised of 8 female and 10 male patients aged from 24~69 year old (mean: 44.2). Of the 18 patients, 8 patients (44.4%) had subarachnoid hemorrhage. 6 patients with subarachnoid hemorrahge were in good neurological status before treatment. Four patients were treated with transcranial surgery and 7 patients with endovascular treatment. the other 7 patient were merely treated with conservative care. All patients were diagnosed with digital subtraction angiography (DSA), but Magnetic resonance angiography (MRA) showed 12 dissecting aneurysms, 2 suspicious cases and 3 normal finding. In the case of anterior inferior cerebellar artery (AICA) dissecting aneurysm, MR angiography showed no visible AICA. Posterior inferior cerebellar artery (PICA) was occluded in postoperative DSA after wrapping of PICA for dissecting aneurysm of proximal protion of AICA. But the patient show no neurologic deficit. One patient developed bilateral vertebral artery dissecting aneurysms. One patient treated only conservative care revealed normal DSA finding on follow-up study. CONCLUSION: DSA is the only accurate diagnostic tool for vertebral dissecting aneurysm. Proximal GDC occlusion of vertebral artery may be a safe and effective therapy for patients with vertebral artery dissecting aneurysm. For proper decision of safe treatment modality, one should consider vertebral artery dominancy, collateral circulation, PICA invasion.

MR Imaging and IVIR Angiography in Patients with Hemifacial Spasm

PURPOSE: To determine the usefulness of MR imaging and MR angiography (MRA) in the evaluation of patients with hemifacial spasm. MATERIAL AND METHODS: One hundred and twenty-five patients with hemifacial spasm were included in this study. Axial T1-, T2-weighted images, proton density image (3mm thickness, 256 x 192) and 3-D TOF MRA were performed. Relation between facial nerve and adjacent arterial structures was carefully evaluated, which was correlated with surgical findings. RESULTS: MRA identified the presen(~e of offending vessels at the root exit zone of facial nerve and its origin in 117 patients(52 PICA, 50 AICA, 6 vertebral artery, 9 dual vessels). There were 4 false negatives and 4 false positives. Vascular groove at the root exit zone was identified in 52 cases, but there was no positive correlation between severity and duration of symptoms. The presence of ipsilateral or contralateral distal loop formation of vertebral artery were noted in 63 patients. In addition, 4 cases of neoplastic and vascular lesions were also demonstrated on MR imaging. CONCLUSION: Combination of MR imaging and MRA is an useful screening modality in the presurgical evaluation of hemifacial spasm, which can demonstrate the offending vessels as well as other pathologic lesions.