ABSTRACT
<p><b>OBJECTIVE</b>To study the influence of the audio-visual block (AB) on the brain glucose metabolism of idiopathic tinnitus patients.</p><p><b>METHODS</b>The brain positron emission tomography (PET) test was performed on one chronic idiopathic tinnitus patient under audio-visual block and non-block (NB) conditions respectively. The visual analysis and statistical parameter mapping (SPM) analysis were both used to detect the brain glucose metabolism difference under AB and NB conditions.</p><p><b>RESULTS</b>Under NB conditions, significant hyperactivity was detected at auditory and visual cortex on both sides of the brain. However, this phenomenon was not shown under AB conditions. Instead, a hyperactivity of brain was presented in the left Wernicke's area.</p><p><b>CONCLUSIONS</b>The generation of chronic idiopathic tinnitus probably has no relationship with the auditory cortex abnormity. Wernicke's area might be involved in the central perception of tinnitus.</p>
Subject(s)
Adult , Humans , Male , Auditory Cortex , Metabolism , Brain , Metabolism , Glucose , Metabolism , Positron-Emission Tomography , Tinnitus , Diagnostic Imaging , MetabolismABSTRACT
Objective To investigate the glucose metabolic pattern of brain functional loop in patients with refractory obsessive compulsive disorder (OCD) using 18 F-FDG PET.Methods Eight patients with refractory OCD and 8 age- and gender-matched healthy volunteers underwent 18F-FDG PET brain imaging.SPM software was used for image post-processing and quantitative analysis.Correlation analysis between 18F-FDG uptake and Yale-Brown obsessive compulsive scale(Y-BOCS) score was performed.Results Compared with the controls,the glucose metabolism of bilateral frontal cortices ( including the rectal gyrus,orbital gyrus and cingulate gyrus),left thalamus,right temporal lobe and bilateral cerebellum in refractory OCD patients increased significantly ( Zmax =3.45 - 5.80,all P ＜ 0.001 ).Bilateral motor cortices and bilateral parietal lobes (BA7),however,showed decreased glucose metabolism (Zmax =3.44 - 4.46,all P ＜0.001 ).Y-BOCS score was positively correlated with the glucose metabolism of the bilateral anterior cingulate cortex (Zmax =3.77,3.48 and 2.97,all P ＜ 0.01 ).Conclusions There is a characteristic metabolic pattern of increased glucose utilization in the fronto-striato-thalamic loop and decreased glucose utilization in bilateral motor cortices and parietal lobes in patients with OCD.The glucose metabolism in the anterior cingulate cortex might serve as a quantitative parameter for the assessment of the severity of OCD.
ABSTRACT
Objective To establish an automatic synthesis method for 11C-carfentanil (CFN) as an novel opiate receptor radioligand and study its biodistribution in rats. Methods 11C-Triflate-CH3 was bubbled into 0.5 mg precursor desmethyl-CFN (which was dissolved in 0.15 ml DMSO) to generate 11C-CFN in a V-tube at room temperature. Sep-Pak C2 column was used for purification of 11C-CFN, which was eluted by 3ml binary system aqueous solution, 10 ml water thrice, and then I ml ethanol. The biodistribution (% ID/g) of 11C-CFN in SD rats was studied. SPSS 13.0 was used for statistical analysis. Non-normal distribution data were analyzed using nonparametric test. Results The synthesis time for 11C-CFN was 20 min (end of bombardment, EOB). The synthesis yield was (35.5 ± 2.2) % on average (n = 12, uncorrected)with the radiochemical purity over 98%. Biodistribution study in rats showed that the tracer had a high brain uptake, rapid blood clearance, and a metabolic pathway via liver and kidney. The highest tracer uptake was in thalamus (4.26 ± 0.89) % ID/g and striatum (4.05 ± 1.08) % ID/g at 5 min after injection, followed by cerebral cortex (2.63±0.89) %ID/g, pons (2.26 ±0.57) % ID/g, hippocampus (2. 17 ±0.55) %ID/g and cerebellum (2. 15 ±0.39) %ID/g. Conclusions The automatic synthesis of 11C-CFN is fast and reliable, and this radioligand can be used for opiate receptor imaging.