[Improved localization of spinal AV fistulas using contrast-enhanced MR angiography at 3 T].
OBJECTIVE
The standard for the detection and localization of spinal dural and perimedullary AV fistulas has been digital subtraction angiography. The purpose of this study was to correctly locate dural AV fistulas using high-resolution (hr), contrast-enhanced (ce) MRA at 3 T or at least to estimate the site within a range of two to three segments. As a result, the radiation exposure, contrast dose and risk of complications were able to be reduced.


METHODS
Five patients with typical clinical symptoms and the characteristic signs in spinal MRI were examined at 3 T (GE Signa Excite HD). Hr, ce MR angiography and a time-resolved sequence (TRICKS) were compared and correlated with the subsequent DSA and the operation record with respect to the site of the fistula. In addition, the amount of contrast agent and the number of selectively catheterized segmental arteries in DSA were analyzed.


RESULTS
In all patients, a dural AV fistula was able to be demonstrated by hr, ce MRA, and the side and the segmental level of the point of the fistula were correctly predicted and confirmed in subsequent DSA as well as in the operation record. In time-resolved MRA the determined location was correct in one of the five cases. In the remaining 4 cases no definitive mapping was possible.


CONCLUSIONS
In hr, ce MRA at 3 T the localization of the point of the fistula in a spinal AVF is highly reliable so that the radiation time and the amount of contrast medium can be reduced. Hr, ce MRA is superior to the time-resolved sequence (TRICKS).
Boeckh-Behrens
T
T
Abteilung für Neuroradiologie, Klinikum der LMU München, Standort Grosshadern, Marchioninistrasse 15, Munich. Tobias.BoeckhBehrens@med.uni-muenchen.de
Bitterling
H
H
Schichor
C
C
Brückmann
H
H
Seelos
K
K
D000368:Aged; D015901:Angiography, Digital Subtraction; D020785:Central Nervous System Vascular Malformations / Q000175:diagnosis* / Q000601:surgery; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives; D008875:Middle Aged; D009942:Organometallic Compounds; D012680:Sensitivity and Specificity; D013116:Spinal Cord / Q000098:blood supply*
D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine