Quantitative evaluation of crossed cerebellar diaschisis, using voxel-based analysis of Tc-99m ECD brain SPECT.

BACKGROUND In the recent literature there is no consensus regarding the relationships between crossed cerebellar diaschisis (CCD) with the primary lesion size, severity or location. Thus, the aim of the present study was to investigate relationship between the size and severity of cerebral lesions and CCD in patients with chronic stroke, using voxel-based analysis of Tc-99m ECD single-photon emission computed tomography (SPECT). MATERIAL AND METHODS We retrospectively reviewed data of 57 patients with chronic ischemic lesions localized unilaterally in the cerebral hemisphere. SPECT evaluation was performed with the voxel-based analysis. The percentage inter-hemispheric asymmetry index (AI) and the volume of abnormal clusters of voxels (CV) were ascertained for hypoperfusion in the supratentorial lesion and contralateral cerebellum. RESULTS CCD was present in 35.1% cases. In Group CCD (+), the CV and AI of supratentorial hypoperfusion (median 128.1 ml and 21.9%, respectively) were significantly higher compared with Group CCD(-) (median 41.4 ml and 18.0%, respectively). Statistically significant correlation was found between CV of supratentorial and cerebellar perfusion defects (r = 0.4; p < 0.05), between AI of supratentorial and cerebellar perfusion defects (r = 0.6; p < 0.05) and between CV of supratentorial defect and AI of cerebellar perfusion defects (r = 0.6; p < 0.05). CONCLUSIONS Our data suggest, that in the chronic stage of stroke, the size and severity of the supratentorial lesion are determinants of CCD, correlating with the degree of cerebellar hypoperfusion.