Correlation between brain cortex metabolic and perfusion functions in subjective idiopathic tinnitus.

Objectives: Subjective tinnitus has associated with abnormal brain metabolism and perfusion found in functional imaging studies by fluorodeoxyglucose (FDG) and technetium99m (TC99m). But there is no study evaluating the association of brain metabolism and perfusion abnormalities in a group of these subjects. The aim of this study was to investigate if there is any significant correlation between the brain perfusion and metabolism abnormalities in subjects with tinnitus.

Pattern of brain blood perfusion in tinnitus patients using technetium-99m SPECT imaging.

Background And Purpose: Tinnitus is associated with an increased activity in central auditory system as demonstrated by neuroimaging studies. Brain perfusion scanning using single photon emission computed tomography (SPECT) was done to understand the pattern of brain blood perfusion of tinnitus subjects and find the areas which are mostly abnormal in these patients.

Materials And Methods: A number of 122 patients with tinnitus were enrolled to this cross-sectional study.

Functional brain abnormalities localized in 55 chronic tinnitus patients: fusion of SPECT coincidence imaging and MRI.

Tinnitus is often defined as the perception of sounds or noise in the absence of any external auditory stimuli. The pathophysiology of subjective idiopathic tinnitus remains unclear. The aim of this study was to investigate the functional brain activities and possible involved cerebral areas in subjective idiopathic tinnitus patients by means of single photon emission computerized tomography (SPECT) coincidence imaging, which was fused with magnetic resonance imaging (MRI).

Evaluation of [(201)Tl](III) Vancomycin in normal rats.

Background: Tl-201 has potential in the preparation of radiolabelled compounds similar to its homologues, like In-111 and radiogallium. In this paper, recently prepared [(201)Tl](III) vancomycin complex ([(201)Tl](III)VAN) has been evaluated for its biological properties.

Material And Methods: [(201)Tl](III)VAN was prepared according to the optimized conditions followed by biodistribution studies in normal rats for up to 52 h.

Evaluation of [67Ga]-insulin for insulin receptor imaging.

Background: Radiolabelled human recombinant insulin can be used for the imaging of insulin receptors in some tumours where FDG has natural uptake and diminishes the value of its imaging.

Material And Methods: Insulin was successively labelled with [(67)Ga]-gallium chloride after conjugation with freshly prepared cyclic DTPA-dianhydride (HPLC radiochemical purity assay > 96%) followed by biodistribution studies in normal rats, white blood cell labelling and preliminary SPECT studies.

Results: In vitro studies demonstrated the retention of radiolabelled insulin receptor affinity using freshly prepared human white blood cells at different blood sugar conditions.