[Value of cranial MRI in the follow-up of dural sinus thrombosis]

Abstract

Introduction: At the present time it is well established that cranial magnetic resonance (MR) is the imaging technique of choice for diagnosis of thrombosis of the dural sinuses. However, few studies have been done to evaluate its role in follow-up in this cerebrovascular disorder.

Objective: To assess the alterations in resonance signal in follow-up of patients with thrombosis of the dural sinuses and the clinical correlation of this.

Material and methods: We reviewed the clinical histories of 12 patients diagnosed on cranial MR as having thrombosis of the dural sinuses; 8 cases were also seen again six months later. The cranial MR study was done using a 1.5 or 1.0 T superconductive apparatus to do measured spin-echo sequences (SE) in T1 and T2 in sagittal, transverse and coronal planes. The time elapsed between diagnosis on MR and clinical diagnosis was between 24 hours and 6 months.

Results: All patients had stronger resonance signals in T1 and T2 indicating a subacute phase of the thrombosis (oxidative conversion of deoxyhaemoglobin to methoxyhaemoglobin) and complete absence of blood flow in the sinuses. The eight patients seen again after six months were found to be normal on neurological. On cranial MR partial recanalization was seen in 5 of these (62%).

Conclusion: Changes in the resonance signal persist for a long time both with and without signs of recanalization. This finding does not affect the medium term clinical course.