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Objective To study the radiation level in the surrounding of patients undergoing 99Tcm-MDP SPECT bone imaging and associated influencing factors and provide experimental data for the radiation safety of personnel around the patients.Methods A total of 367 patients undergoing whole-body bone imaging in Cancer Hospital,Chinese Academy of Medical Sciences were investigated to measure the ambient dose equivalent rate around the patients at different time and different distances from the patients,analyze the variations of ambient dose equivalent rate with time and distances,estimate the dose level at different distances around the patients,and evaluate the radiation dose to personnel around the patients.Results The ambient dose equivalent rate around the patient decreased exponentially with time;the effective half-life of 99Tcm in patients' body increased with time.The ambient dose equivalent rate varied by power function with increasing distance within 4 meters from the patient with the mean power value of -1.45.The radiation levels were 238.3 μSv at 0.5 m,99.7 μSv at 1 m,and 61.8 μSv at 1.5 m from the patient undergoing 99Tcm injection to its vanishing in patients' body.At different time points,the radiation doses at 0.5 m off the patient for 10 min were:9.9,3.0,1.9 μSv at 0,3 and 6 h,respectively.Conclusions The ambient dose equivalent rate around the patients undergoing 99Tcm-MDP SPECT bone imaging decrease rapidly with increasing time and distance.The patients can cause a certain degree of exposures to the surrounding personnel,but the exposure level is far lower than the relevant national standards.It is suggested that the patients should not receive other types of diagnosis and treatments spending lot of time and in close contact with medical staff while bone imaging being conducted on the same day.
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Objective@#To analyze the clinical value of SPECT/CT in diagnosis of skull base bone invasion and clinical decision-making for nasopharyngeal carcinoma (NPC), and to compare their diagnostic value with SPECT/CT, CT, MRI, and MRI combined with SPECT (MRI-SPECT) for skull base bone invasion.@*Methods@#Before treatment, among 348 newly diagnosed NPC patients, CT scan was performed in 186 patients (group A) and the remaining 162 patients received MRI scan (group B). Clinical doctors then made clinical management decisions according to the CT or MRI results. After that, all patients underwent 99Tcm-MDP SPECT/CT examination for nasopharyngeal local tomography, and the results were provided to the clinical doctors to make clinical management decisions again. The changes between the two clinical management decisions were scored according to diagnosis, range of lesion, staging, treatment regimens, and auxiliary examination. The diagnostic value of CT scan, MRI scan, SPECT/CT and MRI-SPECT for skull base bone invasion was then evaluated and compared.@*Results@#In terms of changes in scores of clinical management decisions, the score of group A was 1.387 and group B was 0.951, showing a significant difference between the two groups by Wilcoxon test (Z=6.570, P<0.001). By χ2 test, there were correlations between CT and SPECT/CT (χ2 =98.495, P<0.001), and between MRI and SPECT/CT (χ2 =32.662, P<0.001). The consistency of CT and SPECT/CT (Kappa=0.713) was greater than MRI and SPECT (Kappa=0.449). The sensitivity of CT, MRI, SPECT/CT and MRI-SPECT was 67.1%, 84.5%, 90.8% and 100%, the specificity was 73.3%, 92.3%, 85.6% and 84.6%, and the area under the ROC curve was 0.702, 0.884, 0.882 and 0.923, respectively.@*Conclusions@#SPECT/CT has important impact on clinical management decision for NPC. In the judgement of skull base invasion, the diagnostic value of SPECT/CT is significantly higher than CT and approximately equal to MRI. SPECT/CT should be one of the routine examination methods of nasopharyngeal carcinoma. In addition, in view of its greater diagnostic value, MRI combined with SPECT should be the focus of future imaging studies.
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Objective To study serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and its correlation with accumulation degree of 99Tcm-MDP on bone and arthritis and to study the role of sICAM-1 in the diagnosis of patients with early RA. Methods Serum levels of sICAM-1 were measured by immunoenzymetic assay (ELISA). 99mTc-MDP scintigraphy was carried out for the same patients. The significant test between serum levels of sICAM-1 of three groups was performed with analysis of variance; Correlations between serum levels of sICAM-1 and index of semiquatitive 99Tcm-MDP were obtained using sperman's ranks correlation method. Results Compared with control group,serum levels of sICAM-1 were significantly higher in standard group (group A) (P<0.01) and non-standard group (group B) (P<0.05). No significant difference was found between group A and B(P>0.05). Serum levels of sICAM-1 were positively correlated with 99Tcm-MDP scintigraphy. Most patients of non-standard group and standard group showed visible medium-high uptake of 99Tcm-MDP. While control group had not obviously uptake of 99Tcm-MDP. Conclusion Serum levels of sICAM-1, semiquatitive 99Tcm-MDP scintigraphy, accumulation degree of radiopharmuceuutial on bone and arthritis are helpful for diagnosis of early rheumatoid arthritis and judge-ment of the clinical status and improvement of the prognosis.