Localization of clinical syndromes using DWI: two examples of the "capsular" warning syndrome.

The capsular warning syndrome (CWS) is a subtype of transient ischemic attack characterized by its recurrent nature, absence of cortical signs, and high probability of early capsular stroke. Currently, standard imaging techniques have identified only internal capsule lesions in this entity. The authors present 2 cases with an otherwise typical CWS in whom a brainstem stroke was detected by diffusion-weighted imaging (DWI). DWI's ability to differentiate between acute and chronic infarcts may assist in more accurate localization of clinical syndromes.