Posterior circulation infarct is a debilitating disease and often easily missed as it may mimic any peripheral causes of vertigo.
A 61 years old lady with underlying diabetes mellitus and hypertension presented with symptom of vertigo for nearly two hours before she decided to come to the Emergency Department. It was associated with nausea and vomiting and she could not walk due to it. On examination, the DixHallpike test was positive on the right side. Cerebellar signs were not elicited and there was no focal neurological deficit. Blood investigations were reported to be normal. Her symptom of vertigo improved after administering intravenous prochlorperazine and she was subsequently discharged with a scheduled follow up. However, fourteen hours later, she returned with worsening of vertigo and a deteriorating GCS requiring airway protection.
There exists a dilemma when differentiating a central or peripheral cause of vertigo. When a stroke which is one of the central causes of vertigo is missed, the consequences can be profound. Therefore, a non-invasive 3 steps bedside clinical examination like HINTS test (Head Impulse-NystagmusTest of Skew) should be practiced in every patient that presents with vertigo. As reported by one study, it is 100% sensitive and 96% specific for detecting posterior circulation stroke.
A high index of suspicion of posterior circulation infarct should always be raised in patients with persistent, unresolved vertigo. The HINTS test is capable to distinguish between stroke and other peripheral causes of vertigo as it has a high sensitivity and specificity.