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Background: The use of a normal database for [I]FP-CIT SPECT imaging has been found to be helpful for cases which are difficult to interpret by visual assessment alone, and to improve reproducibility in scan interpretation. The aim of this study was to assess whether the use of different tomographic reconstructions affects the performance of a normal [I]FP-CIT SPECT database and also whether systems benefit from a system characterisation before a database is used. Seventy-seven [I]FP-CIT SPECT studies from two sites and with 3-year clinical follow-up were assessed quantitatively for scan normality using the ENC-DAT normal database obtained in well-documented healthy subjects. Patient and normal data were reconstructed with iterative reconstruction with correction for attenuation, scatter and septal penetration (ACSC), the same reconstruction without corrections (IRNC), and filtered back-projection (FBP) with data quantified using small volume-of-interest (VOI) (BRASS) and large VOI (Southampton) analysis methods. Test performance was assessed with and without system characterisation, using receiver operating characteristics (ROC) analysis for age-independent data and using sensitivity/specificity analysis with age-matched normal values. The clinical diagnosis at follow-up was used as the standard of truth. Results: There were no significant differences in the age-independent quantitative assessment of scan normality across reconstructions, system characterisation and quantitative methods (ROC AUC 0.866-0.924). With BRASS quantification, there were no significant differences between the values of sensitivity (67.4-83.7%) or specificity (79.4-91.2%) across all reconstruction and calibration strategies. However, the Southampton method showed significant differences in sensitivity between ACSC (90.7%) vs IRNC (76.7%) and FBP (67.4%) reconstructions with calibration. Sensitivity using ACSC reconstruction with this method was also significantly better with calibration than without calibration (65.1%). Specificity using the Southampton method was unchanged across reconstruction and calibration choices (82.4-88.2%). Conclusions: The ability of a normal [I]FP-CIT SPECT database to assess clinical scan normality is equivalent across all reconstruction, system characterisation, and quantification strategies using BRASS quantification. However, when using the Southampton quantification method, performance is sensitive to the reconstruction and calibration strategy used. [ABSTRACT FROM AUTHOR]

Background: Mesolimbic and nigrostriatal dopaminergic pathways play important roles in both the rewarding and conditioning effects of drugs. The dopamine transporter (DAT) is of central importance in regulating dopaminergic neurotransmission and in particular in activating the striatal D2-like receptors. Molecular imaging studies of the relationship between DAT availability/dopamine synthesis capacity and active cigarette smoking have shown conflicting results. Through the collaboration between 13 SPECT centres located in 10 different European countries, a database of FP-CIT-binding in healthy controls was established. We used the database to test the hypothesis that striatal DAT availability is changed in active smokers compared to non-smokers and ex-smokers., Methods: A total of 129 healthy volunteers were included. Subjects were divided into three categories according to past and present tobacco smoking: (1) non-smokers (n = 64), (2) ex-smokers (n = 39) and (3) active smokers (n = 26). For imaging of the DAT availability, we used [123I]FP-CIT (DaTSCAN) and single photon emission computed tomography (SPECT). Data were collected in collaboration between 13 SPECT centres located in 10 different European countries. The striatal measure of DAT availability was analyzed in a multiple regression model with age, SPECT centre and smoking as predictor., Results: There was no statistically significant difference in DAT availability between the groups of active smokers, ex-smokers and non-smokers (p = 0.34). Further, we could not demonstrate a significant association between striatal DAT and the number of cigarettes per day or total lifetime cigarette packages in smokers and ex-smokers., Conclusion: Our results do not support the hypothesis that large differences in striatal DAT availability are present in smokers compared to ex-smokers and healthy volunteers with no history of smoking.

Background/aims: The aim of present study is to evaluate the predictive and prognostic role of high [18F] fluoro-D-glucose (FDG) uptake of primary tumor and nodal metastasis in squamous cell carcinoma of head and neck (HNSCC)., Methodology and Patients: Between February 2006 and July 2010, we retrospectively evaluated 64 patients with primary HNSCC in an institutional imaging trial. All patients who underwent evaluation pretreatment FDG-positron emission tomography/computarized tomography (FDG-PET/CT) imaging and 33 (51%) had pre- and after treatment FDG-PET/CT imaging. All treatments were performed with curative intent. Abnormal FDG uptakes were analyzed using maximum standardized uptake values (SUVm). The disease-free survival (DFS) and overall survival (OS) were evaluated with several prognostic factors such as pre-treatment SUVm and %change in SUVm., Results: Tumor sites are nasopharynx (n=29, 45.3%), larynx (n=16, 25%), oropharynx (n=13, 20.4%) and hypopharynx (n=6, 9.4%). Median age was 58 (range: 16-87) and most patients (84.4%) had stage III/IV lesions. Objective response rate was 78.2%. The median primary tumor SUVm was 13.4 (range, 4.8-33.1), median nodal SUVm was 4.45 (range, 0-25.6) and median % change in SUVm was 74.1 (range, -61-100). On multivariate analysis, nodal SUVm and surgery remained significant predictors of DFS. There was no statistical significance found between survival and other factors., Conclusions: We have found that while nodal SUVm is prognostic for DFS, primary tumor SUVm and % change in SUVm are not.

Crossed aphasia (CA) refers to aphasia occurring after right brain damage in right handers. In the literature, numerous CA cases following cerebral ischemia have been reported, but few met the criteria for a prompt diagnosis. The authors present the case of a 52-year-old woman with SAH caused by a right middle cerebral artery (MCA) saccular aneurysm who developed non-fluent aphasia characterized by reduced verbal output, word-finding disturbances and phonemic paraphasias in both oral and written language. 99mTc-HMPAO SPECT was also consistent with right parieto-temporal and frontoparietal ischemia with crossed cerebellar diaschisis on the right cerebellum. A diagnosis of CA was made. One year follow-up showed improvement in communication skills but persistent right fronto-temporo-parietal ischemia. Cerebral vasospasm after aneurysmal SAH symptomatology may vary from motor and sensory disturbances to cognitive disabilities. Aphasia developing after cerebral ischemia of the right hemisphere in a right-hand dominant patient following vasospasm may be a misleading symptom for the localization of the insult. Keeping a high index of suspicion may help in making the correct diagnosis. The changes in the perfusion patterns of cerebellum as assessed by SPECT study during the acute and recovery phases suggests the involvement of cerebellum in language functions.