Localization of the central sulcus by using superimposed activation SPECT and MRI

The authors have described the functional localization of the central sulcus in six cerebral hemispheres of four patients. In this regard, recent studies have indicated that the increase in the distribution of 99mTc-HMPAO and 123I-IMP to reflect physiologic changes in the regional cerebral blood flow, and the changes can be detected with single photon emission computed tomography (activation SPECT). SPECT images are limited in accurately localizing anatomical structures, and magnetic resonance (MR) images can not identify functional brain areas. However, when a SPECT image, obtained during a 'finger opposition task', was superimposed on a matched MR image, the contralateral sensorimotor area of the hand region was localized in five cerebral hemispheres of three patients and the central sulcus also was identified. It thus appears that superimposition of a matched set of a SPECT image and a MR image of an activation provides a convenient method to preoperatively assess the central sulcus. (author)