Review Question - QID 214695

This patient likely has a left cerebellar stroke/lesion as demonstrated by her vertigo, unilateral dysmetria (i.e., decreased finger-to-nose and heel-to-shin tests), and left-leaning gait.

The cerebellum, also known as the “little brain”, is responsible for coordinating movement, motor planning, and balance. It is supplied by the superior cerebellar artery, anterior inferior cerebellar artery, and the posterior inferior cerebellar artery. Lesions at the cerebellum present classically with severe vertigo, nystagmus, ipsilateral dysmetria, abnormal dysdiadochokinesia (rapid alternating movement, and body sway towards the side of the lesion. Patients often also experience moderate to severe headaches, especially in the occipital area. Diagnosis is often made via imaging studies such as magnetic resonance imaging and/or computed tomography. Common complications include edema, brainstem compression, and progressive hydrocephalus. Management involves supportive care (e.g., blood pressure management) and surgical interventions (e.g., craniectomy or ventriculostomy) in patients with obstructive hydrocephalus or progressive brainstem compression.

Incorrect Answers:
Answer 1: Bleeding into the subarachnoid space describes subarachnoid hemorrhage, which classically presents as “the worst headache of the patient's life.” It can occur after trauma or secondary to the rupture of an aneurysm or arteriovenous malformation. This patient’s headache is only rated as a 6/10, and she has lateralizing/focal neurologic deficits that are uncommon in subarachnoid hemorrhage.

Answer 2: Dislodged otoliths into the semicircular canals describes benign paroxysmal positional vertigo (BPPV), one of the most common causes of vertigo. Patients complain of brief episodes of vertigo lasting several seconds that are brought on by head movement. This patient’s persistent vertigo for 2 hours that is not associated with head movement is not consistent with the presentation of BPPV.

Answer 3: Inflammation of the inner ear describes labyrinthitis or vestibular neuritis, a benign, self-limited disorder. It is understood to be a viral or post-viral inflammatory disorder affecting the vestibular portion of the eighth cranial nerve. Symptoms often present during or after a viral illness. Although this patient reports a cold 2 weeks ago, her lateralizing/focal neurologic deficits are not seen in patients with the condition.

Answer 5: Lesion at the left medial medulla often presents with contralateral paralysis of both the upper and lower limbs, vertigo, and ipsilateral hypoglossal dysfunction. This patient has retained strength and no cranial nerve XII deficits on physical examination.

Bullet Summary:
Lesions at the cerebellum present with severe vertigo, nystagmus, headache, and ipsilateral dysmetria and ataxia.