Stereotactic radiosurgery for the treatment of dural arteriovenous fistulas involving the transverse-sigmoid sinus.
OBJECTIVE
The aim of this study was to assess the efficacy and safety of radiosurgery for the treatment of dural arteriovenous fistulas (DAVFs) located in the region of the transverse-sigmoid sinus.


METHODS
A series of 20 patients with DAVFs located in the transverse-sigmoid sinus, who were treated with gamma knife surgery between June 1995 and June 2000, was evaluated. According to the Cognard classification, the DAVF was Type I in four patients. Type IIa in seven, Type IIb in two, and combined Type IIa+b in seven. Nine patients had previously been treated with surgery and/or embolization, whereas 11 patients underwent radiosurgery alone. Radiosurgery was performed using multiple-isocenter irradiation of the delineated DAVF nidus. The target volume ranged from 1.7 to 40.7 cm3. The margin dose delivered to the nidus ranged from 16.5 to 19 Gy at a 50 to 70% isodose level. Nineteen patients were available for follow-up review, the duration of which ranged from 6 to 58 months (median 19 months). Of the 19 patients, 14 (74%) were cured of their symptoms. At follow up, magnetic resonance imaging and/or angiography demonstrated complete obliteration of the DAVF in 11 patients (58%), subtotal obliteration (95% reduction of the nidus) in three (16%), and partial obliteration in another five (26%). There was no neurological complication related to the treatment. One patient experienced a recurrence of the DAVF 18 months after angiographic confirmation of total obliteration, and underwent a second course of radiosurgery.


CONCLUSIONS
Stereotactic radiosurgery provides a safe and effective option for the treatment of DAVFs involving the transverse and sigmoid sinuses. For some aggressive DAVFs with extensive retrograde cortical venous drainage, however, a combination of endovascular embolization and surgery may be necessary.
Pan
David Hung-chi
DH
Department of Neurosurgery, Veterans General Hospital-Taipei, VACRS, Taiwan, Republic of China. hcpan@vghtpe.gov.tw
Chung
Wen-yuh
WY
Guo
Wan-you
WY
Wu
Hsiu-mei
HM
Liu
Kang-du
KD
Shiau
Cheng-ying
CY
Wang
Ling-wei
LW
D000293:Adolescent; D000328:Adult; D000368:Aged; D020785:Central Nervous System Vascular Malformations / Q000175:diagnosis / Q000601:surgery*; D002533:Cerebral Angiography; D003392:Cranial Sinuses; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D016634:Radiosurgery; D016896:Treatment Outcome