Contrast-enhanced time-resolved MRA for pre-angiographic evaluation of suspected spinal dural arterial venous fistulas.
BACKGROUND
Spinal digital subtraction angiography (DSA) is the gold standard for diagnosis of spinal dural arterial venous fistulas (SDAVFs), but can require extensive time, radiation exposure and contrast dose. We hypothesize that contrast-enhanced time-resolved MR angiography (CE-TR MRA) will have utility for the non-invasive diagnosis and pre-angiographic localization of SDAVFs.


METHODS
Eighteen patients underwent both CE-TR MRA and DSA for suspected SDAVFs, with DSA performed a median of 11 days (range 0-41) after MRA. CE-TR MRA was performed on a 1.5 T GE unit using Time Resolved Imaging of Contrast Kinetics (TRICKS). CE-TR MRA and DSA images were evaluated for the presence of SDAVFs and location of the feeding arterial supply, with DSA as the reference standard. DSA was also evaluated for the number of vessels catheterized, contrast volume and fluoroscopic and procedure times.


RESULTS
Eight of the 18 patients were positive for SDAVF on DSA. Sensitivity, specificity, positive predictive value and negative predictive value for the 18 CE-TR MRAs were 88%, 90%, 88% and 90%, respectively. Localization of the SDAVF arterial supply on CE-TR MRA was within one vertebral level from DSA for 6/7 SDAVFs. Compared with patients with a SDAVF and feeding artery identified on CE-TR MRA, patients with negative or suboptimal CE-TR MRA had a significantly increased number of vessels catheterized (p=0.027) and larger contrast volumes (p=0.022).


CONCLUSIONS
CE-TR MRA is a useful initial examination for the diagnosis and localization of SDAVFs, with a high concordance rate with DSA. When CE-TR MRA demonstrates a SDAVF, the number of catheterized vessels and contrast dose can be decreased during DSA.
Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, USA.
Amit M
AM
Saindane
Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, USA.
Srikanth R
SR
Boddu
Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, USA Department of Neurological Surgery, Emory University School of Medicine, Atlanta, Georgia, USA.
Frank C
FC
Tong
Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, USA.
Seena
S
Dehkharghani
Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, USA Department of Neurological Surgery, Emory University School of Medicine, Atlanta, Georgia, USA.
Jacques E
JE
Dion
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods; D020785:Central Nervous System Vascular Malformations / Q000000981:diagnostic imaging*; D003287:Contrast Media; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013116:Spinal Cord / Q000000981:diagnostic imaging*; D013997:Time Factors
D003287:Contrast Media
Fistula; Magnetic Resonance Angiography; Spine; Technique