Obtain MRI Brain to Rule Out Central Nervous System Pathology
Given the massive headache preceding vertigo onset and negative Dix-Hallpike maneuver, you must obtain neuroimaging—specifically MRI brain with attention to the posterior fossa—to exclude cerebellar or brainstem stroke, vestibular migraine, or other central causes before assuming a benign peripheral vestibular disorder. 1
Why Imaging is Critical in This Case
The combination of severe headache followed by persistent vertigo with a negative Dix-Hallpike maneuver represents red flags that distinguish this from typical BPPV:
Failure of Dix-Hallpike to reproduce symptoms raises concern that the underlying diagnosis is not BPPV, as this maneuver should be diagnostic for the most common cause of triggered episodic vertigo 2, 1
The massive headache preceding vertigo onset strongly suggests either vestibular migraine or a posterior circulation vascular event (cerebellar or brainstem stroke), both of which require different management than peripheral vestibular disorders 1
Up to 10% of cerebellar strokes present similarly to peripheral vestibular processes, making clinical differentiation challenging without imaging 1
The American Academy of Otolaryngology-Head and Neck Surgery explicitly recommends neuroimaging when there are "additional signs and/or symptoms inconsistent with BPPV" 1
Complete Neurological Examination First
Before ordering imaging, perform a focused neurological examination looking for:
Direction-changing nystagmus without head position changes or downbeating nystagmus on Dix-Hallpike, which indicate central pathology 1
Dysarthria, dysmetria, or dysphagia, which are key distinguishing features of cerebellar stroke 1
Sensory or motor deficits, Horner's syndrome, or other focal neurological findings 1
Inability to stand or walk, which warrants urgent evaluation 3
Any of these findings mandate immediate MRI evaluation 1, 3
Repeat Vestibular Testing
While arranging imaging, repeat diagnostic maneuvers that may have been inadequately performed:
Perform bilateral Dix-Hallpike maneuvers to assess both posterior semicircular canals 1
Conduct supine roll test to evaluate for lateral canal BPPV, which the standard Dix-Hallpike may miss 1, 3
Document any nystagmus characteristics carefully, as atypical nystagmus patterns suggest central pathology 1
Most Likely Diagnosis: Vestibular Migraine
If MRI excludes structural CNS pathology, vestibular migraine becomes the leading diagnosis given:
Vestibular migraine accounts for up to 14% of vertigo cases and has a 3.2% lifetime prevalence 1
Diagnostic criteria include ≥5 episodes of vestibular symptoms lasting 5 minutes to 72 hours, current or history of migraine, and ≥1 migraine symptom during at least 50% of dizzy episodes 1
The severe headache preceding vertigo onset fits this pattern perfectly 1
Treatment Algorithm Based on Final Diagnosis
If Vestibular Migraine Confirmed:
First-line: Lifestyle modifications including dietary modifications, regular sleep schedule, and adequate hydration 1
Preventive medications: Beta-blockers or topiramate for recurrent episodes 1
Acute attack management: Triptans for concurrent headache and short-term antiemetics 1
If Lateral Canal BPPV Identified on Repeat Testing:
Perform appropriate canalith repositioning procedures (Barbecue roll maneuver for lateral canal BPPV), which achieve 90-98% success rates 1
Consider vestibular rehabilitation if multiple repositioning attempts fail 1
Critical Pitfalls to Avoid
Do not prescribe vestibular suppressants (meclizine, dimenhydrinate) as primary treatment, as they do not address the underlying cause and may delay recovery 1
Do not assume BPPV when Dix-Hallpike is negative, as this warrants further evaluation for alternative diagnoses 1
Do not delay neurological evaluation when red flags are present—the severe headache preceding vertigo is a red flag requiring imaging 1
Do not rely solely on CT imaging, as MRI has superior sensitivity (11% detection rate vs 6% for CT) for detecting acute brain lesions in atypical vertigo presentations 2
Medication Consideration
While Orilissa (elagolix) can cause fatigue as a side effect 4, there is no established association between elagolix and vertigo or dizziness in the literature reviewed. This medication is unlikely to be the primary cause of her symptoms.