Cases · RVAS · clinician

Dizziness when reversing the car

A 68-year-old retired engineer with stereotyped dizziness on sustained head rotation.

Vignette

A 68-year-old retired engineer presents with three months of stereotyped dizziness — but only when he holds his head turned to the right for 30 seconds or more. The trigger is highly reproducible: reversing the car, looking over his right shoulder at his grandchildren, and once during a yoga class. During an episode he experiences light-headedness, brief horizontal double vision, and on two occasions has had to sit down because he felt he might fall. Episodes resolve within seconds of bringing his head back to neutral. He has hypertension, hypercholesterolaemia, and is a former smoker. He has no neck pain at rest.

Examination and workup

Cervical examination shows reduced right cervical rotation (50° vs 70° on left) with end-range stiffness. Cervical torsion test negative. JPE and SPNT normal. Dix-Hallpike, supine roll, vHIT, audiometry, VNG all normal. On gentle sustained right cervical rotation in clinic (carefully, with explicit consent and a chair behind him), at 45° rotation for 25 seconds he develops his characteristic light-headedness and a transient skew deviation, which resolves immediately on returning to neutral.

Question

What is the most appropriate next investigation?

ACervical-spine MRI to look for structural cervical pathology
BDynamic transcranial or cervical duplex Doppler in neutral and at the provocative rotation
CTrial of upper-cervical manipulation to release the stiff right rotation
DVestibular rehabilitation with habituation to head rotation
EMigraine prophylaxis with propranolol, given the symptom episodic nature

Select an option to reveal the answer.

Teaching point

RVAS is rare but consequential — the one cause of position-evoked dizziness on this differential that can produce a brainstem stroke. The clinical hallmark is **brainstem symptoms reproducibly triggered by sustained head rotation**, not the proprioceptive symptoms of cervicogenic dizziness. Dynamic Doppler screens, dynamic CTA or MRA confirms structural cause, and DSA is the gold standard for surgical planning. Manipulation and habituation are both contraindicated until RVAS is excluded.

References

²⁴ Choi K-D, Choi J-H, Kim J-S, Kim HJ, Kim M-J, Lee T-H, et al. (2013). Rotational vertebral artery occlusion: mechanisms and long-term outcome. Stroke, 44(7):1817–1824. link
³⁵ Duan G, Xu J, Shi J, Cao Y (2016). Advances in the pathogenesis, diagnosis and treatment of Bow Hunter's syndrome: a comprehensive review of the literature. Interventional Neurology, 5(1–2):29–38. link
³³ Cheronis CD, Cory MJ, Aslam M, Jefferson E, Spinks E, Knipper E, et al. (2024). The use of dynamic magnetic resonance angiography in the diagnosis of rotational vertebral artery syndrome. Annals of the Child Neurology Society, 2(4):319–324. link
³⁶ American College of Radiology Expert Panel on Neurological Imaging (2021). ACR Appropriateness Criteria — Dizziness and Ataxia. Journal of the American College of Radiology, 18(5S):S147–S159. link