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

BACKGROUND: In the recent literature there is no consensusregarding 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 relationshipbetween the size and severity of cerebral lesions and CCD in patientswith chronic stroke, using voxel-based analysis of Tc-99mECD single-photon emission computed tomography (SPECT).MATERIAL AND METHODS: We retrospectively reviewed dataof 57 patients with chronic ischemic lesions localized unilaterallyin the cerebral hemisphere. SPECT evaluation was performedwith the voxel-based analysis. The percentage inter-hemisphericasymmetry index (AI) and the volume of abnormal clusters ofvoxels (CV) were ascertained for hypoperfusion in the supratentoriallesion and contralateral cerebellum.RESULTS: CCD was present in 35.1% cases. In Group CCD(+), the CV and AI of supratentorial hypoperfusion (median128.1 ml and 21.9%, respectively) were significantly highercompared with Group CCD(–) (median 41.4 ml and 18.0%,respectively). Statistically significant correlation was foundbetween CV of supratentorial and cerebellar perfusion defects(r = 0.4; p < 0.05), between AI of supratentorial and cerebellarperfusion 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 stageof stroke, the size and severity of the supratentorial lesion aredeterminants of CCD, correlating with the degree of cerebellarhypoperfusion