Contrast-Enhanced Cerebral MR Venography Overcomes Causes of Drop of Signal in Time of Flight MR Venography

Abstract
Background: Cerebral venous thrombosis is uncommon disease with vague manifestations. Magnetic resonance venog-raphy (MRV) plays an important role in its diagnosis. The cardinal MRV sign of venous sinus thrombosis is sinus drop of signal. Using time of flight MR venography (TOF MRV) -the commonly used technique there are multiple causes of signal drop simulating dural sinus thrombosis.
Aim of Study: To diagnose different causes of signal drop on TOF MRV using contrast enhanced MRV to avoid misin-terpretation of dural sinus thrombosis.
Patients and Methods: 79 patients with clinical suspicion of cerebral venous sinus thrombosis underwent cerebral 2D-TOF and post-contrast MRV (time-resolved imaging of contrast kinetics (TRICKS) MRV in 40 patients & elliptic centric MRV in 39 patients). Findings in TOF MRV were compared to those in contrast-enhanced MRV.
Results: Dural sinus thrombosis was seen in 30 cases. Turbulence of flow in superior sagittal sinus and lateral sinuses was demonstrated in 8 cases, hypoplastic transverse sinus was diagnosed in 23 cases, atretic transverse sinus was shown in 2 cases, stenosis of the transverse sinus was seen in 7 cases. 10 cases demonstrated normal dural sinuses on all used MRV techniques.
Conclusion: Drop of signal in dural venous sinuses using TOF MRV has many causes other than thrombosis. To avoid misinterpretation it is important to use contrast enhanced MRV either TRICKS or elliptic centric techniques.