Effect of Hyperosmolar Therapy on Cerebrovascular Circulation and Dynamics in Patient with Cerebral Venous Sinus Thrombosis (P1.244)

Objective: We investigated the effects of mannitol infusion on clinical and imaging parameters in patients with cerebral venous sinus thrombosis (CVST). Background: Hyperosmolar therapy is commonly used in varied neurological and neurosurgical patients. Effects of hyperosmolar therapy is still unsettled specially site of action of these hyperosmolar agents on different parts of cerebral circulation. Patients with CVST were selected as they have preserved arterial inflow allowing mannitol to exert its action on different components of cerebral circulation which was then studied radiologically. Methods: Five patients with CVST without parenchymal lesions were prospectively included. Each patient underwent clinical assessment and magnetic resonance imaging (MRI) of the brain. We looked at vascular congestion with susceptibility weighted imaging (SWI), cerebral perfusion with pulsed arterial spin labelling (pulse ASL) and venous sinuses with conventional sequences of MRI as well as MR venogram. Following infusion of placebo (normal saline) and mannitol (1 gm/kg) parameters were repeated. Results: Patient age ranged between 20-60 years. There were 3 males and 2 females. All patient had prominent vascular congestion most marked on side of headache. (when headache was unilateral). Following normal saline infusion there was no change in headache, vascular congestion, venous sinuses size though there was mild increase in cerebral blood flow (< 5 [percnt]). Following mannitol infusion patient reported dramatic reduction (2 patients) or abolition (3 patients) of headache with concomitant significant reduction in vascular congestion and improved hemispheric perfusion (10- 25 [percnt] increase) with no change in sinus caliber as compared to baseline. Conclusion: Mannitol results in vascular decongestion and also improves cerebral perfusion possibly along with intracranial pressure (ICP) reduction. Patient’s headache improves which could be due to vascular decongestion or ICP reduction thus also suggesting them as potential underlying mechanism of headache in patients with CVST. Disclosure: Dr. Singh has nothing to disclose. Dr. Kulkarni has nothing to disclose. Dr. Saini has nothing to disclose. Dr. Varadharajan has nothing to disclose.