MRI Brain is the Most Important Next Step
In a patient presenting with vertigo, blurred vision worsened by vertical gaze, and isolated vertical nystagmus, urgent MRI brain imaging is the critical next step to rule out posterior fossa stroke or other central nervous system pathology. 1
Why This Patient Requires Urgent Neuroimaging
This clinical presentation strongly suggests central vertigo rather than benign peripheral causes:
Vertical nystagmus is a red flag for central pathology - peripheral vestibular disorders typically produce horizontal or horizontal-torsional nystagmus, not purely vertical nystagmus 1
Blurred vision worsened by vertical gaze combined with vertical nystagmus suggests brainstem or cerebellar involvement affecting the vestibular supranuclear pathways 1
This constellation of findings is consistent with skew deviation, a vertical strabismus caused by disorders affecting the vestibular pathways in the brainstem and cerebellum, including demyelination, ischemia, or mass lesions 1
Why Other Options Are Inappropriate
The Dix-Hallpike maneuver (Option B) is NOT indicated because:
- This test is designed to diagnose benign paroxysmal positional vertigo (BPPV), which causes brief episodes of vertigo triggered by head position changes 2, 3
- BPPV produces horizontal-torsional nystagmus, not vertical nystagmus 2, 3
- The presence of vertical nystagmus makes BPPV extremely unlikely and suggests central pathology requiring imaging 4
Carotid ultrasound (Option A) is not the priority because:
- Anterior circulation disease does not typically cause isolated vertigo with vertical nystagmus
- The symptoms point to posterior fossa pathology (vertebrobasilar territory) 5
ECG (Option C) is not the immediate priority because:
- While cardiovascular risk factors matter, the acute presentation with vertical nystagmus demands urgent brain imaging first 1
- Cardiac evaluation can be pursued after excluding stroke
The Critical Diagnostic Pathway
Immediate neuroimaging is essential because:
- Approximately 4% of isolated dizziness cases are due to stroke, with 70% located in the posterior circulation 4
- Vertical nystagmus, neurological symptoms (blurred vision with vertical gaze), and the acute presentation mandate urgent MRI with diffusion-weighted imaging to detect ischemia, demyelination, or mass lesions 1, 4
- MRI brain with and without contrast is the preferred imaging modality for evaluating suspected brainstem and cerebellar pathology 1
After imaging, neurological consultation is warranted for further evaluation and management of the underlying central cause 1
Common Pitfall to Avoid
Do not assume this is benign peripheral vertigo simply because the remainder of the neurological exam appears normal. Normal neurological examination does not exclude posterior circulation infarct, and vertical nystagmus is a specific indicator of central pathology that requires immediate investigation 4. The three-day duration with persistent vertical nystagmus and visual symptoms makes peripheral causes like vestibular neuronitis highly unlikely 1.