MRI of clot in cerebral venous thrombosis: high diagnostic value of susceptibility-weighted images.
OBJECTIVE
In cerebral venous thrombosis (CVT), the sensitivity of conventional MRI sequences to detect clot in the sinuses or veins is incomplete and largely depends on the time elapsed since thrombus formation. Little is known concerning the corresponding diagnostic value of fluid-attenuated inversion recovery (FLAIR), echo-planar T2* susceptibility-weighted imaging (T2*SW) or diffusion-weighted images (DWI).


METHODS
We performed a retrospective analysis of 114 MRI examinations from 39 patients with CVT using a structured assessment. The time course of sensitivity in the detection of clot (n=166 clots) was analyzed for different MR sequences using a multilevel logistic model. The sensitivity of different MR sequences for diagnosis of cortical venous thrombosis was tested separately (n=38 clots).


RESULTS
The sensitivity of T2*SW and T1-weighted spin echo image (T1SE) sequences to detect clot in the sinuses or veins was estimated at 90% and 71% between day 1 and day 3, which was much higher than that of T2SE, FLAIR or DWI during the first week of clinical onset. The sensitivity of T2*SW was stable in the first week. After this period, the sensitivity of T2*SW decreased less than that of T1SE. Thrombosed cortical veins, even in the absence of visible occlusion on magnetic resonance venography, were detected more frequently with T2*SW (97%) and T1SE (78%) than with FLAIR or DWI (<40%).


CONCLUSIONS
T2*SW imaging appears to be of additional diagnostic value in CVT. The T2*SW sequence may be particularly useful during the acute phase of CVT when the sensitivity of the other sequences is incomplete and for the diagnosis of isolated cortical venous thrombosis.
Idbaih
Ahmed
A
Department of Neurology, Hopital Lariboisière, Paris, France.
Boukobza
Monique
M
Crassard
Isabelle
I
Porcher
Raphaël
R
Bousser
Marie-Germaine
MG
Chabriat
Hugues
H
D000293:Adolescent; D000328:Adult; D002550:Cerebral Veins / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging / Q000592:standards; D004198:Disease Susceptibility; D017352:Echo-Planar Imaging / Q000592:standards; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000592:standards*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013997:Time Factors; D020246:Venous Thrombosis / Q000175:diagnosis*