Annals of nuclear medicine
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Comparative Study Clinical Trial Controlled Clinical Trial
Development of "super rapid dynamic SPECT," and analysis of retention process of 99mTc-ECD in ischemic lesions: comparative study with 133Xe SPECT.
To analyze the retention process of technetium-99m ethyl cysteinate dimer (99mTc-ECD) in normal and ischemic lesions, we developed a super rapid dynamic SPECT system based on the CERASPECT (DSI, Inc., Waltham, MA, USA). The system made it possible to take a SPECT series every 2 seconds. Each SPECT series contains a maximum of 16 slices (6.6 mm slice interval) in a matrix size of 32 x 32. ⋯ The early phase images of 99mTc-ECD SPECT within 20 seconds by the super rapid dynamic SPECT were very useful to the same extent as the 133Xe-rCBF SPECT for detecting mild or moderate ischemic lesions. This study suggests that esterase activity, participating in the ECD retention mechanism, may be tolerable to mild or moderate ischemia. This tolerance may be the main cause of the nonlinear relationship between ECD accumulation and cerebral blood flow.
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Comparative Study
Positron emission tomographic imaging with 11C-choline in differential diagnosis of head and neck tumors: comparison with 18F-FDG PET.
The aim of this study was to evaluate the clinical value of positron emission tomography (PET) with 11C-labeled choline (CHOL) for the differential diagnosis of malignant head and neck tumors from benign lesions as compared with 18F-fluorodeoxyglucose PET. ⋯ The results of this study indicate that CHOL PET may be feasible clinically for head and neck tumor imaging. PET imaging with CHOL seems to be able to detect malignant head and neck tumors as effectively as FDG PET. The advantages of CHOL PET were shorter examination period and low uptake in the muscle. However, both CHOL and FDG have some limitations in the evaluation of salivary gland lesions.
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Comparative Study
Clinical significance of cerebrovascular reserve in acetazolamide challenge -comparison with acetazolamide challenge H2O-PET and Gas-PET.
The response of cerebral blood flow (CBF) to acetazolamide (ACZ) challenge is frequently determined in clinical settings to evaluate cerebrovascular reserve (CVR). A reduced CVR can indicate patients with occlusive cerebrovascular disease and compromised hemodynamics who may be at increased risk of cerebral ischemia. However, how precisely ACZ reflects cerebral hemodynamic impairment remains obscure. The present study aims to clarify the pathological significance of CVR in patients with occluded carotid arteries. ⋯ CVR could be applied as an index reflecting both autoregulatory capacity and OEF. The present study also supported the notion that SPECT with ACZ challenge can be clinically applied to detect misery perfusion.
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Clinical Trial Controlled Clinical Trial
Methionine positron emission tomography for differentiation of recurrent brain tumor and radiation necrosis after stereotactic radiosurgery--in malignant glioma.
Following stereotactic radiosurgery (SRS), we examined how to differentiate radiation necrosis from recurrent malignant glioma using positron emission tomography (PET) with 11C-methionine (Met). ⋯ There were no significant differences between recurrent malignant glioma and radiation necrosis following SRS in Met-PET. However, this study shows Met-PET has a sensitivity and accuracy for differentiating between recurrent glioma and necrosis, and presents important information for developing treatment strategies against post radiation reactions.
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Clinical Trial Controlled Clinical Trial
Alveolar epithelial permeability in patients with primary spontaneous pneumothorax as determined by Tc-99m DTPA aerosol scintigraphy.
Primary spontaneous pneumothorax (PSP) occurs subsequent to a disruption in the continuity of visceral pleura and escape of air into the pleural space. The cause of PSP is most often the rupture of subpleural blebs or bullae. It is usually difficult to detect evidence of pulmonary pathology. The purposes of the present study were (1) to investigate the changes of pulmonary alveolar epithelial permeability in patients with PSP as determined by Tc-99m DTPA aerosol lung scintigraphy, (2) to assess whether or not some differences exist between apical and basal parts of the lungs, and (3) to determine the relationship between the clearance rate of Tc-99m DTPA and the PFT results, the recurrence rate of PSP, and the percentage of pneumothorax in affected lung. ⋯ This study demonstrates that pulmonary epithelial permeability is not altered in PSP patients; the clearance rate of Tc-99m DTPA shows no difference between apical and basal parts of each lung.