Diagnosis of posttraumatic transverse sinus thrombosis with magnetic resonance imaging/magnetic resonance venography: report of two cases.

Cerebral venous sinus thrombosis is an uncommon but potentially lethal condition that can present with headache, focal deficits, seizures, altered mental status, and papilledema. Nontraumatic dural sinus thrombosis is associated with medical conditions such as oral contraceptive use, pregnancy, dehydration, coagulopathies, connective tissue disorders, and leukemia. Traumatic dural sinus thrombosis has been primarily diagnosed at autopsy and was originally considered benign. The superior sagittal sinus (SSS) has been the main structure associated with traumatic sinus thrombosis. Traumatic thrombosis of other venous sinuses, such as the transverse sinus (TS), is thought to be uncommon but may be underdiagnosed using standard imaging techniques. During the evaluation of patients who have sustained head trauma, posttraumatic sinus thrombosis, although uncommon, should be considered in the differential diagnosis because of its potentially lethal consequences. A patient with an undiagnosed sinus thrombosis can suddenly worsen if the thrombosis spreads from a sinus to a cerebral vein, leading to epilepsy, neurologic deficits, or death. Furthermore, some authors have ascribed sinus thrombosis a pathogenetic role in the formation of vascular malformations such as dural arteriovenous fistulas (AVFs). In the adult patient, dural AVFs are generally accepted as being acquired disorders because adults with dural AVF frequently have etiologic risk factors for venous sinus thrombosis, including head trauma, neurologic surgery, and ear or sinus infection. Animal models have also supported the theory that sinus thrombosis contributes to the development of dural vascular malformations. Thus, early recognition and diagnosis of venous sinus thrombosis is important for both the acute and long-term management of patients with this potentially lethal condition. Recognition of cerebral sinus thrombosis can be aided by the use of computed tomographic (CT) scans, angiograms and, most recently, magnetic resonance imaging (MRI) and magnetic resonance venography (MRV). The cases presented here illustrate the role of MRV in the diagnosis of cerebral venous sinus thrombosis after head trauma.