SPECT and PET cerebral scintigraphy of tinnitus

1818 Objectives 1.Identify common structural/functional abnormalities of severe and disabling central type disabling tinnitus in brain with HmPAO SPECT and F-18 FDG PET of over 300 patients. 2.Support the clinical diagnosis and therapy of multiple types of tinnitus as an aberrant auditory sensory disorder of ear and brain with sensory-affect connectivity. Methods 1. Apply standardized medical-audiologic tinnitus protocol for patient inclusion. 2. Perform standard multidetector SPECT after injection of Tc99m HMPao and/or 3. Perform standard PET with MRI fusion or PET/CT after injection of F-18FDG. 4. SPECT analysis:compare ROI/Pons brain ratios in tinnitus and normal patients. 5. FDG PET analysis:compare SUVs of multiple standardized patient ROIs to normal age and sex matched group data. Results 1. SPECT-Brodman 21 and 22(auditory association),right thalamus, posterior superior pons(region of cochlear and vestibular nuclei),multiple cerebellar ROIs abnormal(p 2std dev). 3. FDG PET-frequent concurrent biparietal +/- frontal cortical abnormal SDAT-associated findings. 4. FDG PET followup study quantitative data parallels individual therapeutic responses. Conclusions 1. Medial temporal lobe hypometabolism is common/universal pathophysiology in central disabling tinnitus. 2. Primary and secondary auditory association cortex abnormalities common. 3. Thalamic, pons, and cerebellar abnormalities reflect sensory-affect connectivity. 4. Preclinical SDAT -type hypometabolism is a frequent association. Research Support Martha Entehman Foundation