[An assessment of the thalamocortical sensory pathway based on small infarcts in the corona radiata on CT].

Although lacunar syndrome is relatively commonly encountered in patients with a lacunar infarct in the deep cerebral white matter, the responsible lesions are often unidentified. By examining eight patients with lacunar syndrome who had small infarcts in the deep cerebral white matter, an attempt was made to determine the position and distribution of the sensory pathway on brain CT at the level of the splenium of the corpus callosum. When the distance from the frontal crista to the superior saggital sinus sulcus was defined as 1.0, the position of the corticospinal tract was located in the portion from 0.45 to 0.49 and that of the sensory pathway in the portion from 0.49 to 0.53. These data indicated that the position of the sensory pathway was just behind the corticospinal tract and the distribution was very narrow at this level. The results of this assessment revealed that lacunar infarcts in the deep cerebral white matter were liable to cause sensorimoter syndrome more than pure sensory stroke.