Making the diagnosis
Differential diagnosis
VM is criterion D made concrete: it can only be diagnosed once the look-alikes are excluded. Duration and the hearing picture do most of the discriminating work.
The great overlapper
Several conditions cause repeated dizzy spells. The clues that separate them are how long each spell lasts, whether the hearing changes, and what else happens during the attack.
The key contrast is with Ménière’s disease: both cause episodic vertigo with nausea, but Ménière’s brings fluctuating low-frequency sensorineural hearing loss, tinnitus and aural fullness localised to one ear, whereas VM spares the hearing.3 The two genuinely coexist more often than chance, which muddies the water.
Beware the traps: VM and Ménière’s overlap and can co-occur; isolated vertigo is rarely vascular but a posterior-circulation event must never be assumed away in the at-risk; and persistent daily symptoms point to PPPD, which frequently follows an acute vestibular event including a VM attack.2 Probable VM is the honest label while the picture declares itself.
VM against its mimics
Vestibular migraine is held as the reference row; tap a mimic to surface the single feature that most reliably separates it.1
Tap a mimic to reveal the key discriminator.
When to step outside the criteria
New, sustained or progressive neurological symptoms, a first severe attack in an older patient with vascular risk factors, or any focal brainstem/cerebellar sign should prompt urgent imaging rather than a VM label — see the acute vertigo and HINTS chapters. Documented progressive hearing loss should redirect you to Ménière’s.
Key points
- VM is a diagnosis of exclusion — duration and hearing do most of the discriminating.
- Ménière’s is the key audiovestibular contrast (progressive low-frequency SNHL); it can also coexist.
- Seconds-long positional spells suggest BPPV; persistent daily symptoms suggest PPPD.
- Never assume away a posterior-circulation event in the patient with vascular risk.