Stereotactic radiosurgery for tentorial dural arteriovenous fistulae draining into the vein of Galen: report of two cases.
OBJECTIVE
Treatment of tentorial dural arteriovenous fistulae (DAVFs) primarily draining into the vein of Galen remains a therapeutic challenge. We present two cases of ruptured galenic DAVFs that were successfully treated with gamma knife radiosurgery.


METHODS
Patient 1, a 66-year-old woman, experienced a sudden onset of headache and loss of consciousness. Neuroimaging studies revealed intraventricular hemorrhage and a DAVF with aneurysmal dilation of the vein of Galen. The DAVF was supplied by tentorial branches of the right meningohypophyseal artery and bilateral supracerebellar arteries, which drained directly into the vein of Galen. Patient 2, a 64-year-old woman, experienced subarachnoid hemorrhage. Cerebral angiography revealed a galenic DAVF at the falcotentorial junction, which was supplied by bilateral supracerebellar arteries. This patient had an aneurysm at the origin of the left supracerebellar artery.


METHODS
Both patients were treated with gamma knife radiosurgery. In each case, the fistula was exclusively targeted and a dose of more than 20 Gy was delivered. Complete obliteration of the fistula was confirmed 27 and 29 months after radiosurgery for Patients 1 and 2, respectively, whereas the normal venous structures of the galenic system were preserved.


CONCLUSIONS
Gamma knife radiosurgery is an effective treatment modality for DAVFs primarily draining into the vein of Galen. Irradiation doses of more than 20 Gy, strictly limited to the fistulae, seem to be sufficient for successful obliteration of these high-risk vascular lesions, with minimal invasiveness.
Shin
M
M
Department of Neurosurgery, Faculty of Medicine, University of Tokyo Hospital, Japan.
Kurita
H
H
Tago
M
M
Kirino
T
T
D000368:Aged; D001164:Arteriovenous Fistula / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D002526:Cerebellar Diseases / Q000175:diagnosis / Q000601:surgery*; D002533:Cerebral Angiography; D002550:Cerebral Veins / Q000473:pathology / Q000503:physiopathology*; D004388:Dura Mater / Q000098:blood supply*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D016634:Radiosurgery; D013238:Stereotaxic Techniques; D014711:Vertebral Artery / Q000000981:diagnostic imaging