Precise localization of dysfunctional areas in vertebro-basilar infarctionby FDG- and O-15-H2O-PET using standardized image analysis and image registration to 3-D MR

The advantages of standardized multimodal image analysis are demonstrated i n a case of symptomatic tremor after basilar thrombosis. Functionally and s tructurally lesioned areas were mapped in Talairach space using 3-D MRI, ce rebral FDG-PET and O-15-H2O-PET. Structural lesions were found in the left midbrain, thalamus, putamen and cerebellar areas. Voxel-based statistics in comparison to a normal data base revealed hypomelabolism in the left thala mus, left red nucleus, left cerebellar hemisphere including dentate nucleus and in the left inferior olivary nucleus. The O-15-H2O-PET investigation r evealed metabolic uncoupling along the rubroolivocerebellar loop. Given the delicate anatomy of the structures involved, image registration and standa rdized image analysis techniques are essential for a synoptic multimodality analysis of morphological and functional pathology and should generally be used for cerebral PET investigations.