Purpose Clinical approach for staging cerebral venous sinus thrombosis (CVST) depends on the duration from symptom onset to clinical diagnosis, which is subjective and may be incorrect. To investigate if T1-weighted signal characteristics of the thrombus can be used for staging the thrombus on segment level and predicting endovascular therapy outcome. Methods Ninety-one CVST patients underwent non-contrast-enhanced T1-weighted 3D variable-flip-angle fast-spin-echo (T1-SPACE) and 29 of them received endovascular therapy. We divided the 91 patients into acute, subacute, and chronic CVST stage according to the clinical approach, and then analyzed the T1 weighted signal characteristics (i.e., thrombus shape and signal intensity) of the thrombus at each stage. To investigate the endovascular therapy outcome associated with the thrombus stage and signal characteristics, we evaluated the thrombolytic ratio on patient level and recanalization rate on segment level, respectively. Results The thrombi at acute or chronic stage were depicted as isointense signals but as hyperintense signals at subacute stage. Compared to the thrombus at acute stage, the thrombus at chronic stage was contractive and can be distinguished. Developing thrombi at transition periods of acute-to-subacute or subacute-to-chronic stage were found appearing mixed iso-/hyper-intense signals. On patient’s level, the patients at earlier stage had higher thrombolytic ratio (acute: 80.7 ± 18.3%, subacute: 62.6 ± 36.3%, chronic: 22.9 ± 24.2%). On segment level, the thromboembolic segments of isointense or mixed iso-/hyper-intense thrombi at non-chronic stage had good thrombolytic outcome. Conclusion T1-weighted signal characteristics of the thrombus can be used for staging CVST and predicting the endovascular therapy outcome.

Objectives Catheter-directed thrombolysis (CDT) is an effective therapy for acute deep vein thrombosis (DVT). However, predicting the CDT outcomes remains elusive. We hypothesized that the thrombus signal on T1-weighted black-blood magnetic resonance (MR) can provide insight into CDT outcomes in acute DVT patients. Methods A total of 117 patients with acute iliofemoral DVT were enrolled for T1-weighted black-blood MR before CDT in this prospective study. Based on the signal contrast between thrombus and adjacent muscle, patients were categorized into the iso-intense thrombus (Iso-IT), hyper-intense thrombus (Hyper-IT), and mixed iso-/hyper-intense thrombi (Mixed-IT) groups. Immediate treatment outcome (i.e., vein patency) and long-term treatment outcome (i.e., the incidence rate of postthrombotic syndrome) were accessed by the same expert. Histological analysis and iron quantification were performed on thrombus samples to characterize the content of fibrin, collagen, and the ratio of Fe3+ to total iron. Results Compared to Mixed-IT and Hyper-IT groups, the Iso-IT group had the best lytic effect (90.5 ± 1.6% vs. 78.4 ± 2.6% vs. 46.5 ± 3.3%, p < 0.001), lowest bleeding ratio (0.0 vs. 11.8 vs. 13.3, p < 0.001), and the lowest incidence rate of postthrombotic syndrome on 24 months (3.6 vs. 18.4 vs. 63.4%, p < 0.001) following CDT. The Iso-IT group had a significantly lower ratio of Fe3+ to total iron (93.1 ± 3.2% vs. 97.2 ± 2.1%, p = 0.034) and a higher content of fibrin (12.5 ± 5.3% vs. 4.76 ± 3.18%, p = 0.023) than Hyper-IT. Conclusion Thrombus signal characteristics on T1-weighted black-blood MR is associated with CDT outcomes and possesses potential to serve as a noninvasive approach to guide treatment decision making in acute DVT patients. Key Points