In practice
Disorder-by-modality
For each common vestibular disorder, one modality (occasionally two) carries the diagnostic load. Knowing the characteristic finding — and what it changes — is the half of imaging that survives the actual scan being read by a radiologist.
The table below pairs each disorder with the modality of choice, the characteristic finding, and the management it supports. Click any row to expand the management notes.
Vestibular schwannomais the prototype retrocochlear lesion. On gadolinium-enhanced MRI of the IAC it appears as a well-circumscribed enhancing mass within the canal, classically extending into the CPA — the “ice-cream cone” configuration. Thin-slice FIESTA/CISS resolves the seventh and eighth cranial nerves around it.
Cerebellar infarction is the central mimic to fear. DWI shows restricted diffusion in the affected territory; CTA defines the substrate. PICA territory is the most common (and the territory most likely to present as isolated vertigo), AICA is unique for adding hearing loss because it co-supplies the inner ear, and SCA territory carries a higher risk of mass effect and hydrocephalus.
SSCD is the classic bony pathology, diagnosed on Pöschl-plane HRCT.1 Truly symptomatic patients benefit from plugging.2
Multiple sclerosis requires a brain MRI with 3D-FLAIR and post-Gd T1, plus spinal cord imaging, against McDonald 2017 criteria.3Active plaques enhance with gadolinium.
Endolymphatic hydropscan now be visualised in vivo with delayed 3D-FLAIR after intravenous or intratympanic gadolinium — direct evidence for the substrate of Ménière’s disease.4
Functional vestibular disorders (PPPD, MdDS) typically have a normal structural MRI. Functional imaging shows altered PIVC activity and connectivity — a substrate, even if not yet a clinically deployed biomarker.5
The clinical translation: never call a disorder “imaging-negative” until the right modality has been done in the right plane. Negative axial-only CT is not negative for SSCD; negative non-contrast MRI is not negative for schwannoma; negative structural MRI in PPPD is the expected finding, not a refutation.
The matrix below is for quick reference at the request bench. The italic notes under each row are the management consequence of the finding, since the value of imaging is what it changes.
Hallmark findings — what each disorder looks like
Nine classic imaging signs every clinician evaluating vertigo should recognise on sight. Click any thumbnail to expand the detailed schematic with anatomical labels and a pearl on how the call is actually made.
The matrix
| Condition | Modality of choice | Key imaging finding |
|---|---|---|
| Vestibular schwannoma | Gd-MRI IAC + FIESTA/CISS | Enhancing IAC mass extending into CPA — 'ice-cream cone' configuration |
Management Size-based: observation < 1 cm, stereotactic radiosurgery, microsurgical resection. Hearing preservation depends on early detection. | ||
| Cerebellar infarction | DWI MRI + CTA | Restricted diffusion (PICA, AICA, or SCA territory); CTA may show vessel occlusion |
| Superior canal dehiscence | HRCT temporal bone (Pöschl + Stenvers) | Bony defect at the arcuate eminence over the superior canal |
| Labyrinthitis | T2 + post-Gd T1 MRI | High T2 signal in cochlea/vestibule; labyrinthine enhancement on post-Gd T1 |
| Multiple sclerosis | Brain MRI 3D-FLAIR + post-Gd T1 + spinal cord | Periventricular and brainstem T2/FLAIR plaques; Dawson's fingers; active lesions enhance |
| Perilymphatic fistula | HRCT temporal bone | Pneumolabyrinth — air in cochlea or vestibule; fracture line in trauma |
| PPPD / MdDS (functional vestibular) | fMRI / PET (research) | Altered activity / connectivity in PIVC, insula, thalamus, limbic regions |
| Ménière's disease — hydrops | Delayed 3D-FLAIR + intratympanic or IV Gd | Saccular / cochlear hydrops grade |
Grading endolymphatic hydrops
Delayed 3D-FLAIR after intravenous or intratympanic gadolinium brightens the perilymphatic compartment, leaving the endolymphatic space dark and measurable. The ladder below mirrors the Nakashima / Naganawa scheme — slide through the grades to see the endolymph distend into the perilymph.
Bright outer ring = perilymph (gadolinium-enhanced). Dark inner = endolymph. As hydrops progresses, the dark compartment expands, eating into the bright perilymph — the visual signature of the disease substrate.
Current grade: Endolymph >50% cochlea or >67% vestibule. The radiological correlate of clinical Ménière's.
Pitfalls — what looks like one disorder but is another
- AICA stroke mimicking labyrinthitis — vertigo and hearing loss together can come from either; HINTS and DWI are decisive.
- Thin bone over the superior canal mimicking SSCD — Pöschl plus Stenvers reconstruction settles it; axial review over-calls.
- Intracochlear schwannoma — subtle on routine MRI; high-resolution FIESTA and dedicated cochlear sequences are needed.
- Vestibular neuritis on MRI — many cases now show enhancement of the vestibular nerve, but absence of enhancement does not exclude the diagnosis.
- “Normal” MRI in chronic dizziness — a normal structural MRI is the rule, not the refutation, in PPPD and MdDS.