T2 "Susceptibility Vessel Sign" Demonstrates Clot Location and Length in Acute Ischemic Stroke: e76727

Objectives The aim of our study was to evaluate, in acute ischemic stroke patients, the diagnostic accuracy of the MRI susceptibility vessel sign (SVS) against catheter angiography (DSA) for the detection of the clot and its value in predicting clot location and length. Materials and Methods We identified consecutive patients (2006-2012) admitted to our center, where 1.5 T MRI is systematically implemented as first-line diagnostic work-up, with: (1) pre-treatment 6-mm-thick multislice 2D T2* sequence; (2) delay from MRI-to-DSA 94%. Inter- and intra-observer ICC was excellent for clot length as measured on T2* ([kgreen] greater than or equal to 0.97) and as measured on DSA ([kgreen] greater than or equal to 0.94). Correlation between T2* and DSA for clot length was excellent (ICC: 0.88, 95%CI: 0.81-0.92; Bland & Altman: mean bias of 1.6% [95%CI: -4.7 to 7.8%], Passing & Bablok: 0.91). Conclusions SVS is a specific marker of clot location in the anterior and posterior circulation. Clot length greater than 6 mm can be reliably measured on T2*.