The quality of CT diagnosis depends on the quality of scanning which is related to accurate scanning design and quality control on work process. The quality control of work procedure includes training of patients' breathing, reasonable application of window technique, accurate mark, size and CT value,washing and print of films. In addition, the coordination of clinical doctors, imaging doctors and CT technicians is very important. According to CT standards, precise CT scanning by CT design request, can provide a high quality CT images that reflect pathologic state of human body, thereby to raise the quality of CT diagnosis.

Objective To prepare for extraction of liver focal lesion in view of its characteristics of images. Methods A region of interest in the liver region comprising the focal lesion to create a local image was selected firstly, then the threshold to pre-segment the local image was got automatically by using local OTSU in clusters algorithm, at last mark sifting methods to get red of inner holes and outer dissociate areas to get the final contour was used. Results The algorithm can efficiently extract the focal liver lesion. Conclusion The way of extraction of liver focal lesions with local OTSU and zone market screening is rapid and effective.

A comprehensive overview of CR equipment in the system to use various types of image artifacts and accurate analysis of the reasons for the formation of artifacts; described in detail to avoid and eliminate the artifact method, and measures to solve the work encountered in the actual artifacts of the problem.

Objective To analyze the CT and MRI features of pituitary stalk interruption syndrome, so that to improve the diagnostic knowledge of this disease.Methods The imaging and clinical data of 4 patients with pituitary stalk interruption syndrome were retrospectively analyzed. Results In all of the 4 cases, the pituitary stalk were not shown by CT in 2 and by MRI in 4,the high signal intensity of the posterior lobe disappeared on T1WI,while a small nodule in infundibulum with high signal intensity on T1WI was found. Conclusion MRI is the most valuable imaging modality for the diagnosis of pituitary stalk interruption syndrome.

Lean management theory is applied to the management of the devices and staffs of radiology department. With the current flow evaluated, the working efficiency and patient satisfaction are increased.

It is elaborated the relation between CT's commonly seen hitches and regular maintenance, and problems due to periphery assistant devices cannot be ignored. Based on analyses to CT's problems in usual work, 5 factors should be paid attention to maintain CT. Also, 5 points are raised to radiation protection for CT examination.

Objective To design a speech command module to replace manual command during X-ray examination.Methods The module was composed of the parts for speech,pushbutton actuator,speaker,miniature voice box,power source and etc.The electrical conductors were used to connect the above parts,and the speech command was formed by special software.Results The module had the speech command triggered by the pushbutton,and the speech command was pellucid and clear so that the workload could be decreased.Conclusion The module facilitates the speech command during X-ray examination,and thus is worthy promoting practically.

Objective To evaluate the value of CT scan in diagnosis of the splenic lesions.Methods A retrospective analysis was made on the CT scans of 33 patients with surgically and pathologically proven splenic lesions,which included plain CT scan(n=33),biphasic contrast-enhanced CT scan(n=28)and contrast delay scanning(n=6).Results In 33 cases,non-neoplastic lesions were 6 cases,including tuberculosis(n=2),hematomas(n=3)and inflammatory pseudotumor associated with a cavernous hemangioma(n=1).Benign tumors were 13 cases,including cysts(n=5),hemangiomas(n=4),lymphanioma(n=1)and lymph-hemangiomas(n=3).Malignant tumors were 14 cases,including malignant lymphoma(n=8),metastases(n=4),malignant myofibroblastoma and hemangioendothelial sarcoma(n=1,respectively).Conclusion CT is of significant value in diagnosis of splenic lesions.

Objective To analyze CT characteristics of metastatic liver leiomyosarcoma(MLL),and to improve the diagnostic accuracy of MLL.Methods CT manifestations and clinical characteristics of 5 patients with pathological-proved MLL were retrospectively analyzed.Plain and contrast-enhanced triphase(including arterial,portal phase in all cases and delayed phase in a part of cases) scans were performed.Results On plain scan,all lesions were hypo-dense."Bull-eye-sign" was found in two cases on contrast-enhanced scan,which is the typical metastatic feature.During arterial phase,the smaller lesions showed marked peripheral enhancement and central necrosis.The larger MLL presented as solid-cystic lesions,the parenchyma of tumor was rich in blood supply.Some cases presented mild hypo-dense or iso-dense comparing with the parenchyma of the liver on delayed phase.One case was misdiagnosed as hepatic hemangioma or focal nodular hyperplasia(FNH).Metastases were found out of the liver.Tumor thrombus of portal vein was not found in all of the cases.Conclusion MLL should be considered in the patients with history of extra-hepatic leiomyosarcoma,no marker expressions,no history of hepatitis,no tumor thrombus of portal vein and the special CT findings.

Objective To establish nude mice model of bone metastasis of breast cancer,and study the best method to evaluate the model.Methods The human breast cancer cell,MDA-MB-231PEGFPN,was injected into left ventricule of nude mice to construct the bone metastasis of breast cancer animal model.Methods of X-ray,whole body optical imaging and pathology were used to evaluate the bone damage after six weeks.Results After six weeks,the result of pathology showed that breast cancer cells had already spread to brain,bone marrow and lung of nude mice.The degree of bone destruction was seen clearly in X-ray,and location of breast cancer cells was observed by whole body optical imaging system.Conclusions The results showed that combined application of X-ray,whole body optical imaging and pathology are the best modalities to evaluate bone metastasis of breast cancer in nude mice.