Dysarthria in acute ischemic stroke - Lesion topography, clinicoradiologiccorrelation, and etiology

Background and purpose: Although dysarthria is a frequent symptom in cerebr al ischemia, there is little information on its anatomic specificity, spect rum of associated clinical characteristics, and etiologic mechanisms. Metho ds: An investigation of 68 consecutive patients with sudden onset of dysart hria due to a single infarction confirmed by MRI or CT was conducted. Resul ts: Dysarthria was associated with a classic lacunar stroke syndrome in 52. 9% of patients. Isolated dysarthria and dysarthria-central facial and lingu al paresis occurred in 2.9% (n = 2) and 10.3% (n = 7), respectively. Dysart hria-clumsy hand syndrome was observed in 11.7% (n = 8) of patients and ass ociated with pure motor hemiparesis and/or ataxic hemiparesis in 27.9% (n = 19). The lesions were due to small-vessel disease in 52.9% (n = 36), to ca rdioembolism in 11.8% (n = 8), and to large-vessel disease in only 4.4% (n = 3) of cases. Infarctions were located in the lower part of the primary mo tor cortex (5.9%; n = 4), middle part of the centrum semiovale (23.5%; n = 16), genu and ventral part of the dorsal segment of the internal capsule (8 .8%; n = 6), cerebral peduncle (1.5%; n = 1), base of the pens (30.9%; n = 21), and ventral pontomedullary junction (1.5%; n = 1). Isolated cerebellar infarctions affected the rostral paravermal region in the superior cerebel lar artery territory. Conclusions: Extracerebellar infarcts causing dysarth ria were located in all patients along the course of the pyramidal tract. T his finding correlates with the frequent occurrence of associated pyramidal tract signs in 90.7% (n = 62) of patients. Isolated cerebellar infarcts le ading to dysarthria were in all cases located in the territory of the super ior cerebellar artery.