P040 CSF Leak presenting first as cortical venous thrombosis and then as bilateral subdural haemorrhage

<h3>Introduction</h3> Investigation and management of Spontaneous Intracranial Hypotension (SIH) is an interesting an expanding field in recent years. Presentation typically includes headache with an orthostatic component, although other neurological sequelae including tinnitus/hearing disturbance, dizziness and even dementia have also been described. We present a case report of a patient who presented initially with headaches secondary to cortical venous thrombosis. <h3>Case Description</h3> 42 year old gentleman presented with a 2-week history headache, CT at that time revealing cortical venous thrombosis, for which he was treated with anti-coagulation. Routine follow-up MRI 2-weeks later showed bilateral subdural collections and features in keeping with SIH (Bern Score 9) [figure 1]. MR Spine imaging was subsequently performed, revealing a spinal londitudinally extensive collection (SLEC) ventrally from C2-T2. Prone dynamic myelography and CT confirmed a ventral dural tear at T8/9, secondary to a small osteophytic spur [figure 2]. Following MDT discussion it was decided to perform a targeted blood patch, which was done under fluoroscopic guidance with injection of 20mls autologous blood. <h3>Results</h3> On follow-up, the patients headaches had completely resolved, and imaging findings returned to normal [figure 3]. Cortical venous thrombosis in low intracranial pressure is well recognised, particularly in the setting of lumbar drain insertion. This is likely secondary to venous engorgement and stagnation of flow leading to thrombus formation. Spontaneous CSF leak can also precipitate this condition, and as such is an important diagnostic consideration in these patients. CSF leak should also be considered in those with atraumatic subdural collections. <h3>Disclosure of Interest</h3> no.