[en] This study compared the efficiency of SPECT-CT fused image with planar bone scan, bone SPECT and CT in differentiating malignant from benign lesions and detecting metastases to the spine. Methods. Total 144 patients with spinal lesions underwent planar bone scan (WB), single photon tomography (SPECT), CT and SPECT-CT fused image by a SPECT/CT system. The malignant or benign nature of lesions was proved by radiological Methods, histological findings, 6-24 month follow-up, or all of these. The diagnostic results was divided into 4 types, i.e., normal, benign, doubtful malignant and malignant. Results. There were 137 malignant and 252 benign lesions in 144 patients, respectively. The percentages of doubtful malignant diagnosed by WB, SPECT, CT and fused image are 22.6%, 5.1%, 9.5% and 0%, respectively, p < 0.01-0.001, except for the comparison between the percentages of SPECT and CT. Sensitivities in detection of malignant lesions by WB, SPECT, CT and fused image are 75.2%, 94.2%, 96.6% and 99.3%, respectively, P < 0.001, excepting for the comparisons between those of SPECT and CT, and between those of CT and fused image. The sensitivities m detection of benign lesions by WB, SPECT, CT and fused image are, 56.7%, 86.5%, 90.1% and 96.8%, respectively, P < 0.005 - 0.001, excepting for the comparison between those of SPECT and CT. The specificities in detection of maliganant lesions by WB, SPECT, CT and fused image are 70.6%, 88.9%, 97.2% and 97.6%, respectively, P < 0.001, excepting for the comparison between those of CT and fused image. Conclusion. Bone SPECT-CT fused image has highest diagnostic and differentiating diagnostic values in detection of spinal abnormalities over the planar bone scanning and SPECT. The CT by present SPECT/CT system can complement planar bone scanning and SPECT and is clinically valuable in detection of spinal abnormalities. (authors)

[en] Objective: To study the prognostic value of myocardial perfusion tomographic imaging in patients underwent percutaneous coronary angioplasty (PTCA) plus stent. Methods: 75 patients underwent 99Tcm-MIBI stress-rest myocardial perfusion tomographic imaging 6.91±2.99 months after PTCA. They were followed-up for 41.71±20.00 months, and we recorded unstable angina pectoris, acute myocardial infarction, cardiac death and revascularization for cardiac events. Results: 25 patients had cardiac events during follow-up. And the cardiac event rate in patients with normal and fixed defects (5.9%, 16.7%) was significantly lower than those with reversible defects (52.5%)(χ²=10.94, P<0.017; χ²=6.57, P<0.017). Survival analysis showed that the time free of cardiac event in patients with normal and fixed defects was significantly shorter than those with reversible defects (χ²=7.37, P=0.0066, χ²=6.28, P=0.012), and the mean time free of carciac event in the latter was 33.8±5.0 months. Conclusions: The presence of reversible defects in post PTCA cardiac imaging predicts a higher cardiac event rate, the myocardial perfusion tomography imaging after PTCA is valuable in predicting the prognosis of patients after PTCA plus stent. (authors)

[en] Purpose: Attenuation correction by transmission image has been demonstrated to be a good method to improve the image quality and the diagnostic accuracy of myocardial perfusion. The purpose of this research is to evaluate the myocardial peffusion image with attenuation correction by X-ray. Methods: Twenty-six patients suspected coronary artery disease (CAD) underwent stress-rest 99mTc-MIBI myocardial perfusion image (MPI) with and without X-ray transmission image by an SPECT/CT system, and coronary angiography (CAG). The MPIs were reconstructed into two types: with and without X-ray attenuation correction (AC) and analyzed by nuclear physician. Results: There were 12 patients and 14 patients with and without CAD, respectively. Image quality of MPI with AC is much better than that of MPI without AC. The sensitivity MPI with and without AC in detection of CAD were 83.3% and 91.7%, respectively, p value is 0.537. Both specificities of MPI with and without AC in excluding to CAD were 100%. However, MPI with AC overestimate myocardial perfusion abnormality in anterior wall of let ventricle and underestimate that in posterior wall, compared with MPI without AC. Conclusion: X-ray attenuation correction can obviously improve the image quality of myocardial perfusion image. Myocardial perfusion image with X-ray attenuation correction has comparable diagnostic accuracy to that myocardial perfusion image without attenuation correction. However, its clinical value in detection of coronary artery disease is needed more researches. (authors)

[en] The correct N staging of non-small cell lung cancer(NSCLC) is very important for the option of treatment. ¹⁸F-FDG PET/CT as a new imaging method which combines the advantages of functional and anatomic images has become more and more accurate in the N staging of NSCLC. Numerous researches have proved some risk factors that influenced the mediastinal lymph node metastasis. This review focus on the new parameters and new technologies which improve the accuracy of the N staging of NSCLC recently. (authors)

[en] It is very difficult to differentiate correctly between the benign and malignant solitary pulmonary nodules (SPNs). About 30% of the resected indefinite SPNs are benign. Conventional imaging techniques can identify most patients with SPN, but cannot afford a few patients with SPN which have equivocate manifestations, and each has some limitations. PET-CT is a new imaging technique that can offer metabolic and anatomical information of SPN, which results in higher diagnostic sensitivity and accuracy of SPN. Recently various new imaging method is further improved the diagnostic accuracy. (authors)

[en] The investigation on the synergistic effects among corrosion, slurry erosion and cavitation erosion has special significance for hydraulic turbines operated in Yangtze River and Yellow River where the high concentration solid particles exist in water. Two typical metallic materials i.e. Cr-Mn-N stainless steel and Ni-Ti shapememory-alloy, and two typical materials used for hydraulic turbines 20SiMn and 0Cr13Ni5Mo as compared materials were selected in order to investigate the roles of work-hardening ability and martensitic transformation as well as pseudoelastics in damage mechanism in multiphase flow. Both modified rotating disk rig and ultrasonic vibration facility were used to simulate the possible damage mechanism of materials in multiphase flow. The effects of corrosion on cavitation erosion were investigated through adding 3wt% NaCl. The degradation mechanism was analyzed by electrochemical test, SEM observation, hardness and roughness measurement. The results showed that there was a strong synergistic interaction among electrochemical corrosion, slurry erosion and cavitation erosion for 20SiMn in liquid-solid two-phase medium. In contrast, corrosion played little role for 0Cr13Ni5Mo. Cr-Mn-N stainless steel with high Mn content showed better resistance to cavitation erosion and slurry erosion than 0Cr13Ni5Mo, which was mainly due to its good work-hardening ability as well as strain-induced martensite transformation. The cavitation micro-cracks for Cr-Mn-N stainless steel were parallel to the specimen surface in contrast with 0Cr13Ni5Mo whose micro-cracks were perpendicular to the surface. Ni-Ti alloy with pseudoelasticity showed excellent resistance to combined interaction of cavitation erosion and slurry erosion

[en] Objective: To study the prognostic value of myocardial perfusion tomographic imaging in patients after percutaneous transluminal coronary angioplasty (PTCA) plus stent. Methods: Seventy-five patients underwent ⁹⁹Tc^m-methoxyisobutylisonitrile (MIBI) stress-rest myocardial perfusion tomographic imaging (6.91 ± 2.99) months after PTCA. They were then followed-up for (41.71 ± 20.00) months, and unstable angina pectoris, acute myocardial infarction, cardiac death and revascularization for cardiac events were recorded during follow-up. Results: Twenty-five patients had cardiac events during follow-up. And the cardiac event rate in patients with normal and fixed defects(5.9%, 16.7%) was significantly lower than that in those with reversible defects (52.5%, χ²=10.94, P<0.017; χ²=6.57, P<0.017). Survival analysis showed that the time free of cardiac event in patients with reversible defects was significantly shorter than in those with normal and fixed defects (χ²=7.37, P=0.0066; χ²=6.28, P=0.012), and the mean time free of cardiac event after PTCA was (33.8 ± 5.0) months. Conclusion: The presence of reversible defects on post-PTCA cardiac imaging predicts a higher cardiac event rate, the myocardial perfusion tomography imaging after PTCA is valuable for predicting the prognosis of patients after PTCA plus stent. (authors)

[en] Coronary artery calcification score and myocardial perfusion imaging play important role in the diagnosis, risk stratification, prognosis of coronary heart disease. With the emerging of fusion imaging,the combination of CACS and MPI provides more information to the physician. Out of consideration for radiological dose, low-dose non-gated CT has been used to quantitate the coronary artery calcification. This review focuses on the clinical application of coronary artery calcification score, myocardial perfusion imaging and the combination. (authors)

[en] Objective: To investigate the clinical significance of determination of changes of serum thyroid hormones levels after operation in patients with pituitary ademoma. Methods: Serum FT₃, FT₄,TSH (with CMA) and rT₃ (with RIA) levels were determined in 50 patients with pituitary adenoma both before and one week after operation as well as in 86 controls. Results: The serum FT₄ and rT₃ levels in the patients before operation were significantly lower than those in controls, but the FT3 and TSH levels were not significantly different. Post-operatively, FT3 levels dropped markedly, but rT₃ levels rose markedly while the FT₄, TSH levels were not greatly changed. Conclusion: There were mild thyroid dysfunction in patients with apparently nonfunctioning pituitary adenoma. (authors)

[en] Objective: Imaging quality of myocardial perfusion scintigraphy is important for diagnosis. This study was to evaluate the effects of radiopharmaceutical extravasation on the image quality of myocardial perfusion imaging. Methods: Of 2106 patients who underwent ⁹⁹Tc^m-methoxyisobutylisonitrile (MIBI) rest-stress myocardial perfusion images, there were 25 patients with ⁹⁹Tc^m-MIBI extravasation in their injection sites (20 of them with normal myocardial perfusion imaging). Thirty two patients with normal myocardial per-fusion imaging and coronary angiography were included as the control group. SPSS 12.0 software was used for data analyses. Results: The extravasation group ( 25 person-studies) accounted for 0.59% of all examined patients. The mean radioactivity count of axillary lymph nodes on the extravasation side (144.41 ± 45.45) was significantly higher than that of the control group (78.3 ± 34.42, t=5.983, P<0.001). The radioactivity count of myocardium [(139.38 ± 55.74) vs (225.54 ± 77.02)] and lung [(106.10 ± 61.14 ) vs (162.95 ± 106.05)]of extravasation group was significantly less than that of control group, t=-5.471, -2.276, all P<0.001.The image quality of the control group was significantly better than that of extravasation group(χ²=12.517, P<0.001). Conclusion: Radiopharmaceutical extravasation can reduce the myocardial perfusion image quality by lowering radiopharmaceutical uptake in the myocardium and higher background activity immediately surrounding the heart. (authors)