Diffusion-weighted imaging in transient neurological attacks.

Transient ischemic attack (TIA) can be difficult to diagnose. Episodes of acute atypical or nonfocal neurological symptoms, referred to as transient neurological attack (TNA), are as prevalent as TIAs. Diffusion-weighted imaging (DWI) provides evidence of acute cerebral ischemia in a third of TIA patients. We now report that DWI shows acute ischemia in 23% of patients clinically diagnosed as TNA by experienced stroke neurologists. This questions the accuracy of clinically diagnosing TIA and suggests added value for early magnetic resonance imaging after an episode of acute onset atypical or nonfocal neurological symptoms.