ObjectiveTo improve health care quality and safety by monitoring the performance of PhilipsPrecedence Dual-head single photon emission computed tomography (SPECT). MethodsWith our own homemade point source and the center of rotation model, in accordance with NEMA standards and manufacturers' design conditions, these three indicators including energy peak position of the instrument, intrinsic uniformity and center of rotation were routinely tested between 2008 and 2012 for the Philips-Precedence Dual-head SPECT in our hospital. In addition, the quality control was performed twice a week, and every year the total number of quality control was basically the same. We calculated the results by the weighted average method. ResultsThe 5-year average energy peaks of detector 1 and 2 were (139.23±0.32) and (138.97±0.45) keV, respectively, and they were both within the range of reference values [(140±3) keV]. In addition, the results of center of rotation were also in the normal range, and kept stable. Based on the analysis of quality-control data, for detector 1, compared with the data of 2008, there was no significant diTherence for central field of vision (CFOV) and useful field of vision (UFOV) in these three years from 2009 to 2011 (P>0.05). The diTherence was only significant between data of 2008 and that of 2012 (P<0.05). For detector 2, compared with the data of 2008, there was no significant diTherence for CFOV and UFOV in 2009 and 2011(P>0.05), while there was significant diTherent in 2010 and 2012 (P<0.05). ConclusionThe uniformity of SPECT will gradually deteriorate with prolonged use. However, regular quality control and maintaining can keep the function stabilization, and enhance the availability rate.
ObjectiveTo investigate the diagnostic value of 18F-FDG PET/CT scan for fever of unknown origin. MethodsThe 18F-FDG PET/CT scan results and clinical data were analyzed retrospectively in 32 patients with fever of unknown origin examined between January 2011 and October 2013. Final diagnoses were determined with recognized diagnostic standard. Results18F-FDG PET/CT scan was able to detect the cause of fever precisely in 53.1% (n=17) of the patients and was helpful in 25 patients (78.1%). The final cause of fever was determined in 20 patients, including infection (40%), malignancy (10%), non-infectious inflammatory disease (40%) and miscellaneous causes (10%). True positive, false positive, true negative and false negative rate of the modality were 17.0%, 4.0%, 8.0% and 3.0%; and the sensitivity and specificity were 85.0% and 66.7%. Conclusion18F-FDG PET/CT scan plays an important role in the diagnosis of fever of unknown origin.
This paper is aimed to assess the diagnostic value of MRI versus 99Tcm-methylene diphosphonate (99Tcm-MDP) bone scan (BS) for osseous metastases in patients with prostate cancer. The computer-based retrieval was conducted on PubMed, EMBASE, EBSCO, Web of Knowledge, the Cochrane Library and Ovid data bases to search for trials about diagnosing osseous metastases of prostate cancer with MRI and 99Tcm-MDP BS. Selected with time acceptance and time exclusion criteria, the data quality were evaluated with QUADAS quality assessment tool and collected. We used the Meta-Disc software to conduct meta-analysis, and then calculated the pooled sensitivity, specificity and diagnostic odds ratio (DOR), drew the summary receiving operating characteristic (SROC) curve, and measured the area under curve (AUC) and Q* value. Then five studies were included, involving 353 patients. The pooled sensitivity of MRI and BS was 0.95 (95% CI 0.90~0.98) and 0.67 (95% CI 0.58~0.75), respectively. The pooled specificity was 0.97 (95% CI 0.94~0.99) and 0.88 (95% CI 0.83~0.91), respectively. The pooled DOR was 402.99 (95% CI 119.05~1 364.15) and 23.85 (95% CI 1.32~431.48), respectively. The AUC was 0.990 1 and 0.624 1, respectively. The Q* was 0.958 7 and 0.593 8. It can well be concluded that MRI is more effective than 99Tcm-MDP BS in the diagnosis of osseous metastases in patients with prostate cancer.