The dual source computed tomography is equipped with two X-ray tubes and two corresponding detectors.With its 83 ms-temporal resolution of single segment reconstruction,high quality coronary artery CT angiography can be acquired without heart rate control.Dual energy output by two x-ray tubes improves the differentiation of body tissues,clinical application and lesion diagnostic accuracy of CT.

Objective To discuss the construction and principal of dual-source CT,as well as its superiorities in imaging of heart coronary artery and the clinical application of dual energy technique.Methods The structure of Siemens 64-slice CT was analyzed.The superiorities of dual-source CT in imaging of heart coronary artery were compared with conventional multi-slice CT,and the clinical value of dual energy technique was discussed.Results The dual-source computed tomography had high temporal resolution superiority,and high quality coronary artery CT angiography could be acquired without heart rate control.Dual energy technique could be applied to differentiate tissue component,display given tissue,evaluate the content of iodine in tissue.Conclusion Dual-source CT can not only enhance the diagnosis veracity of pathological changes of heart coronary artery but improve the ability of CT in tissue differentiation.

The low sensibility of MR molecular imaging to signals makes signal amplification exceptionally important.This paper reviews the strategy of the reporter gene signal amplification in MR molecular imaging.

Quantum dots,as nanometer-sized semiconductor crystals,are widely used in life sciences for their excellent optical characteristics.This article introduces the unique optical characteristics of quantum dots and their application in labeling cancer cells and tumor markers as well as in the targeting and imaging of tumor vasculature.

BACKGROUNDTo study the diagnostic value of detection of p16 methylation of sputum exfoliated cells for peripheral lung cancer.

METHODSBefore operation, p16 methylation of the sputum exfoliated cells was detected in 20 normal persons and 50 patients with peripheral pulmonary nodi by p16 methylation-specific PCR (MSP) for judging the nature of the nodi. The results were compared with pathological reports after operation.

RESULTSThe p16 MSP positive rate of sputum exfoliated cells of peripheral lung cancer patients (27/44, 61.4%) was much higher than that of benign pulmonary nodi (1/6, 16.7%) and normal persons (3/20, 15.0%)(Chi-Square=4.281 and 11.869 respectively, both P < 0.05). No significant difference of p16 MSP positive rate of sputum exfoliated cells was found between benign pulmonary nodi and normal persons (Chi-Square= 0.136, P > 0.05). No significant difference of p16 MSP positive rate of sputum exfoliated cells was found between squamous cell carcinoma (13/18, 72.2%) and adenocarcinoma (8/19, 42.1%) (Chi-Square=3.416, P > 0.05 ). If the positive p16 MSP of sputum was chosen as criterion for peripheral lung cancer, its positive predictive value, negative predictive value, sensitivity and specificity were 96.4%, 22.7%, 61.4% and 83.0% respectively.

CONCLUSIONSThe detection of p16 methylation of sputum exfoliated cells is contributable to the diagnosis of lung cancer.

This article is to review the basic principles of renal perfusion in CT and MR,imaging method and perfusion characteristics in kidney diseases.It shows that in addition to the morphologic information,perfusion imaging can also provide functional and metabolic information about the renal neoplasms,which is very helpful for not only the differential diagnosis,but also the evaluation of tumor biological behaviors,it will have a bright future in clinical application.

Objective:To explore the diagnostic value of MRI in the diagnosis ofbone Eosinophilic GranulomaI. Methods:The clinical and imaging materials of 13 patients with eosinophilic granuloma of bone proved by histopathology were analyzed retrospectively.The imaging examination included plain films(n=13),CT(n=12),and MRI(n=13).Results:MR identified all lesions;With one exception,all lesions were hypointense on T1-Weighted images and hyperintense on T2-Weighted images;The lesions and associated soft tissue abnormalities were very conspicuous on short T1 inversion sequences and T1-Weighed post-contrast images;Follow-up MRI studies in two patients after chemotherapy showed decreased size and enhancement of lesions compared with the baseline studies.Three lesions were not identified on plain films.MRI showed greater abnormality than plain radiographs did.CT could identify all lesions also,and the main imaging findings included bone destruction,adjacent bone cortex involvement,periosteal reaction and sof t tissue mass or swelling. Conclusion:MRI can clearly demonstrate the extent of bone involved, the change of soft tissue and sequestrum.It can also acquire the anatomic and pathologicd details of bone and and soft tissue.But X-ray film and CT may improve the diagnostic and differential diagnostic accuracy.

Objective To evaluate the value of multi-slice spiral CT in nasal endoscopic surgery.Methods The multi-slice spiral CT data of 232 patients who were scanned prior to nasal endosopic surgery were analyzed.Results The nasal and sinus disease could be diagnosed correctly with multi-slice spiral CT.The ostiomeatal complex and the channels of the frontal sinus' drainage could be showed clearly.All the manifestation of the multi-slice spiral CT was in correspondence with the endoscopy showed in the surgery.Conclusion The multi-slice CT has the advantages of short scan time,less radiation dosage and multiplanar reconstruction.So it can display the nasal and sinus structures in detail,and has a great value in guiding the nasal endoscopic surgery.

Objective:To investigate the value of ultrasonography in the diagnosis of cystic renal cell carcinoma(CRCC).Methods:To review and analyze 32 cases confirmed by histological examination with the complete data and to sum up their characteristic features of ultrasonographic appearance,and then compared with the results of CT.Results:The sensitivity of ultrasonography in the diagnosis of cystic renal cell carcinoma was 75.00%(24/32),CT was 87.50%(28/32),therefore there was no obvious statistical difference between them.Conclusion:Color Doppler ultrasonography has diagnostic value in cystic renal cell carcinoma.

Atypical teratoid/rhabdoid tumor of the central nervous system has aggressive growth with high potential CSF dissemination and frequently affects very young children.The tumor contains rhabdoid cells and primitive neuroectodermal,malignant mesenchymal and epithelial elements.Immunohistochemistry is helpful in differentiating atypical teratoid/rhabdoid tumor from primitive neuroectodermal tumor/medulloblastoma.Atypical teratoid/rhabdoid tumor is cytogenetically characterized by monosomy 22 or deletion of chromosome band 22q11.2.Intensified therapy combined with surgical resection has been suggested for its treatment.Due to the secondary cystic/necrotic changes and hemorrhage,the imaging features of the tumor are variable.