Diagnostic yield and impact of MRI for acute ischaemic stroke in patients presenting with dizziness and vertigo.

OBJECTIVE

To identify predictors of acute ischaemic stroke (AIS) and evaluate the diagnostic yield and impact of magnetic resonance imaging (MRI) in patients imaged for dizziness and vertigo.

METHODS

Patients imaged using MRI, including diffusion-weighted imaging (DWI) with or without computed tomography (CT), for dizziness and vertigo over a 2-year period were identified retrospectively. MRI findings were categorised as "acute ischaemic stroke", "significant", or "non-significant". We reviewed the medical records to identify presenting symptoms and signs, vascular risk factors, duration of symptoms, and pre- and post-MRI clinical management in patients with proven stroke.

RESULTS

One hundred and eighty-eight patients were included: 39 with vertebrobasilar AIS (20.7%), 32 (17%) with a significant but non-ischaemic abnormality, and 117 (62.2%) with a normal or non-related abnormality. The sensitivity of CT in diagnosing AIS was 9.52% (95% CI: 1.67-31.8%). Posterior inferior cerebellar artery (PICA) territory infarcts were the most common (38.5%). Patients with AIS were significantly more likely to be older than 50 years (p = 0.04), have a greater number of cardiovascular risk factors (p < 0.01), shorter duration of symptoms (p = 0.03), and at least one neurological sign (p = 0.02). DWI MRI had a diagnostic impact on 21.6% patients with stroke.

CONCLUSIONS

MRI plays an important role in differentiating peripheral and central aetiology when this proves challenging clinically. Predictors of AIS were identified that aid patient selection for MRI, to increase the yield and impact of neuroimaging.