ABSTRACT NUMBER: ESOC2026A2490 THROMBOLYSIS OF A POSTERIOR CIRCULATION STROKE - ZERO TO ZERO?

Abstract Background and aims Posterior circulation stroke refers to stroke within vertebrobasilar vascular territory which includes the brainstem, cerebellum, thalami, temporal and occipital lobes. Diagnosis can be challenging, and we report a case which was treated with thrombolysis due to a significant functional deficit, despite a baseline NIHSS of 0. Posterior events score low with standard NIH scoring and thrombolysis in these cases remains controversial, highlighting the necessity of additional functional assessment. Methods A 62-year-old security guard with multiple vascular risk factors presented with sudden onset vertigo. On examination, he was nauseous, had anticlockwise prime position nystagmus and a clumsy left hand, but no drift or ataxia. Previously independent, he was unable to walk, with a broad-based gait. Non-contrast CT head showed no early ischaemic changes while CT angiogram showed possible right vertebral artery dissection. Posterior circulation stroke was clinically diagnosed, and thrombolysis discussed and consented given significant negative impact if deficits persisted. Thrombolysis was given within 4 hours of symptom onset. Results The patient remained well, with no immediate complications and antiplatelets commenced following exclusion of intracranial haemorrhage. He was discharged 4 days later, with community therapy to support gait. Subsequent MRI head demonstrated bilateral cerebellar infarcts. Conclusions This case highlights the limited sensitivity of the NIHSS for posterior circulation strokes and demonstrates how thrombolysis can be used successfully in patients with disabling symptoms, such as gait abnormalities, who do not meet typical criteria for thrombolysis. Such decisions require clear explanation and discussion with patients to allow informed consent. Conflict of interest Callum Cook: nothing to disclose, Su Thiri Aye: nothing to disclose, Dulka Manawadu: nothing to disclose