RÉSUMÉ
<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>
Sujet(s)
Adulte , Humains , Mâle , Cortex auditif , Métabolisme , Encéphale , Métabolisme , Glucose , Métabolisme , Tomographie par émission de positons , Acouphène , Imagerie diagnostique , MétabolismeRÉSUMÉ
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.
RÉSUMÉ
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.