Russell Mitesh Cerejo, MD

Yan S, Chen Q, Xu M, Sun J, Liebeskind DS, Lou M. Thrombus Length Estimation on Delayed Gadolinium–Enhanced T1. Stroke. 2016

The authors, in keeping with their previous studies on thrombus morphology on MRI, have found a new method to assess for thrombus length. They further correlated this thrombus length with recanalization and outcomes with IV thrombolysis. They evaluated patients over ~5 years with acute stroke due to M1 occlusion, received IV thrombolysis and had MRI pre and post thrombolysis. 

They obtained delayed gadolinium-enhanced T1 (dGE-T1) after perfusion imaging and co-registered the imaging with the time of flight MRA. Thrombus length on dGE-T1 was 8.18 ± 4.56 mm (range 1.63-30.26 mm). Recanalization occurred in 38 (51.4%) patients and no recanalization in 36 (48.6%). Thrombus length on dGE-T1 was significantly longer in patients without recanalization in univariate analysis. Thrombus length and M1 occlusion were independent predictors for no recanalization of MCA. Thrombus length of 6.77 mm, yielded a sensitivity of 77.8% and a specificity of 57.9%, and odds ratio 4.81 (95% CI: 1.742 to 13.292; p=0.002). No one achieved recanalization after IVT when length of thrombus exceeded 14 mm on dGE-T1 (see figure).

This study highlights the utility of MRI in assessing thrombus length without increasing the scan time or the contrast load. This may also be useful in acute stroke therapy to determine thrombus length and success of mechanical thrombectomy.