Objective　To evaluate the value of CT MRI in diagnosing skull base chondromas.Methods　8 cases of skull base chondromas were analyzed with etiology,pathology,imaging fetures and differential diagnosis.5 cases were female,3 cases were male,age ranged from 25 to 48 years.The clinical presentation of 8 cases of skull base chondromas had neurologic syndrome.And 3 cases were examined with CT,MR imaging ,4 cases with MR imaging,1 case with CT scanning.Results　In this series of 8 chondromas,3 located in the cavernous sinus,2 in the clival region,2 in the region of jugular foramen,1 in the frontal cranial fossa.Intratumoral calcification was found in 4 cases with CT examination.Heterogeneous enhancement was found in 4 cases with CT examination.The margin of chondromas on CT was well defined.Conclusion　CT have a very important diagnosis values for detecting tumors on chondromas.MRI is superior to CT for delineating the growth style of the tumor and its relationship to the surrounding anatomic structures.

Objective　To study the scan technique that can completely demonstrate the structures of middle-inner ear.Methods　Ninety volunteers underwent 30° axial and 105° coronal HRCT scan.The manifestations of the ministructures of middle-inner ear were observed and their demonstration rate was calculated.The demonstration of different structures of middle-inner ear was evaluated and compared on HRCT.Results　(1)The scan planes of 30° axial and 105° coronal were correspondent to some structures of middle-inner ear and could completely demonstrate them.(2)30° axial and 105° coronal HRCT scan had their own advantages respectively in demonstrating the structures of middle-inner ear.Conclusion　The technique of 30° axial and 105° coronal HRCT scan of middle-inner ear is useful in demonstrating the structures,including the nerve,joint,ligament etc and the relationship among them.

Objective　To define the range of the normal values of MRI signals of hippocampal formation(HPF) for the diagnosis of early stage Alzheimer's disease and hippocampal sclerosis.Methods　MRI signals of 254 normal adults were measured on the transverse section.Results　HPF signal intensities were:T1 relaxation times,629±73 ms;T2 relaxation times,83±5.5 ms;and proton density value,5978±651.The T2 value range(χ±2S)was 72～94 ms,and mean 83 ms.T2 value greater than 104 ms will be associated with evidence of hippocampal pathologic changes.The mixed signal intensity of T2WI(30,60,120)were:3907±407,2657±347,1288±174.The signal intensity ratios of T2WI were:1.02,1.07,1.13.Conclusion　As for the histological features of temporal lobe cortex and HPF,T1relaxation times and proton density values are matched but T2 relaxation times of HPF are relatively longer.

Objective　To investigate the importance of CT diagnosis and differential diagnosis in Wilms′ tumors of children.Methods　45 cases of Wilms′ tumors confirmed by clinical and pathology were retrospectively analyzed,CT characteristics of Wilms′ tumor,renal carcinoma(2 cases),renal rhabdomyosarcoma(1 case)in children were discussed.Results　Wilms' tumors appeared in solid masses in 34 cases (76%),cysticsolid masses in 9 cases(20%),cystic masses in 2 cases (4%),7 cases (15.6%)had thrombosis in renal vein or IVC.Renal carcinoma shared the same appearance with Wilms′ tumor in image.Rhabdoid tumor of kidney appeard as cystic-solid mass with lineal calcification and subcapsular fluid accumulation.Conclusion　Wilms′ tumor is the most popular malignant renal tumors in children.It is originate from renal parenchyma,and likely to invade renal pelvis.Hemorrhhage,necrosis or cystic formation in tumor is common.They are difficult to be distinguished from renal cell carcinomas in radiology.Rhabdoid tumor of kidney is rare and has characteristic features on CT.

Objective　To detect the features of MRI of children leukodystriphies and to provide a heplful method for clinical diagnosis.Methods　The MRI examination was performed in 50 children with leukodystrophies and the cerebral lobes and cerebral special structures involved by lesions were analyzed.Results　1.There were dominant signs of involving parietal and occipital lobes in ALD,besides the two lobes,the frontal lobe was also involved easily in MLD.All lobes were involved in CD and PMD,and frontal lobe was involved in AD early.The central white matter was involved mainly in ALD,but the central white matter was involed only in MLD and the periphery white matter was spared.The central and periphery white matter were all involved in CD,PMD and AD.Furthermore,the cerebellar white matter is also easily involved in ALD and CD.2.The splenium of corpus callosum was mainly involved in ALD,and the splenium,body and knee of corpus callosum were all involved in MLD.But in CD,PMD and AD,the corpus callosum was spared.The back of the posterior limb of internal capsule was involved in ALD,but the all posterior limb of internal capsule was involved in MLD,and the all internal capsule was involved in CD and PMD.On external capsule,ALD involves its posterior part,but CD and PMD involve its all section.A prominet feature of ALD was involving the corticospinal tract of stem and other leukodystrophies don′t involve the corticospinal tract of stem beside one case later-onset GLD.In addition,the lateral lemmiscus was involved easily in ALD,and thalamus was also involved in ALD,MLD and PMD.Conclusion　As a noninvasive,safe and sensitive method,MRI can be used to find the leukodystrophies early.There are relatively characteristic features in different leokodystrophies,which is useful to clinical diagnosis.

Objective　To evaluate the relationship between the tumor encapsulation,lymphocytic infiltration,fibroplasia and cirrhosis and transcatheter arterial chemoembolization(TACE)methods for hepatocellular carcinoma(HCC).Methods　Histopathological changes were studied in 59 cases of HCCs treated with four kinds of TACE and 58 cases of HCCs treated with surgical resection alone.Results　In TACE group the encapsulation,lymphocytic infiltration,fibroplasia was more severe and extensive than that in group of surgical resection alone(Ρ＜0.01）.The TACE method and treatment time had effect on encapsulation and fibroplasia of tumor,but treatment interval was no effect.The rate of cirrhosis among TACE method had no significantly difference（Ρ＞0.05）,had relation to TACE time（Ρ＜0.05）.Conclusion　The changes in the encapsulation,lymphocytic infiltration,fibroplasia are more easily find by polytimes,multimaterial chemoembolization than that by one time single material chemoembolization and chemotherapy alone.The superselective cathetering can avoid the damage of normal liver.

Objective　To investigate the correlation between degree of deeper infiltration of NPC on CT scan,prognosis and expression of P53 protein,in order to further recognize bilogical features of NPC.Methods　Collect 70 NPC biopsy specimens,which had performed CT scan before radiotherapy and had detailed clinical records.The expression of P53 protein was examined by means of S-P immunohistochemical technique.The correlation between expression of P53 protein and peripheral deeper infiltration and prognosis was analysed in detailed.Results　The results of these cases showed that the positive rate of over expression P53 were 68.57%,which had no relation with the histological types and pathological grades.The positive rate of P53 in Ⅱ、Ⅲ types had a higher positive rate than that of the Ⅰ type of NPC.Expression of P53 protein had no relation with neck lymph node metastasis,but had significant correlation with the size of metastatic lymph node,which is the positive rate of P53 in diameter of metastatic lymph node ＜4 cm was higher than that of diameter ≥4 cm.Expression of P53 had no relation with local recurrence and distant metastasis after radiotherapy.Conclusion　With the tumor infiltrating the deeper layer of nasopharynx,the positive rate of P53 expression is more and more high,and degree of malignant is increasing.The three types on CT scan represents the biological features of NPC.

Objective To study the value of reverse CT scan in eliminating the respiratory motion artifacts in the thoracic CT of the patients with chronic obstructive pulmonary diseases(COPD).Methods Fourty patients with COPD were randomly selected and underwent chest CT examinations with the technique of GR-Helical including directive and reverse CT scans.The images were blindly evaluated by three experienced doctors.Results In 40 cases,the respiratory motion artifacts were present in 17 cases,among them,70.59%(12/17) artifacts was in lower lung field,and 64.7%(11/17) artifacts occurred in the people over 60 years of age.The rate of artifact was 35% at directive scan,while it was reduced to 7.5% at reverse scan,the image quality was improved at 27.5%.There was statistical significance in eliminating respiratory motion artifacts between two scanning method (P＜0.05).Conclusion Reverse CT scanning can effectively eliminating or reducing the respiratory motion artifacts in lower lung field,it is the best choice of scanning mode in elderly patients with COPD.

Objective To evaluate the sensitivity and optimized scanning parameter of 64-slice spiral CT in detection of pulmonary nodules with different size and density. Methods Three groups of prosthesis nodules with diameter of 2.5～13 mm and different density (soft-tissue, low density, and ground glass opacity,GGO)were taken into the chest phantom equivalent to human tissue,then scanned with Philips Brilliance 64 scanner in standard dose(tube voltage:120 kV, tube current: 250 mAs)and low-dose(tube voltage:120 kV, tube current: 50, 30,and 21mAs) respectively. The radiation dose(CTDIw and DLP) of the scans, Hounsfield unit(HU) and standard deviation(SD) of CT values in different regions of the phantom, and visibility of the nodules was assessed and recorded.Results The radiation dose of 64-slices spiral CT scanning in low-dose(tube current 21～51 mAs) decreased to 8%～20% of which scanning in standard-dose(250 mAs). There was no statistical difference between the CT values in different regions of the phantom (P>0.05), while the SD of CT values was of statistical significantce (P<0.001) and SD increased with the increment of the density under different scanning parameters. None of the nodules besides of GGO nodules with 2.5 mm and 4 mm in size scanned at 21 mAs was invisible. Conclusion GGO nodules of 2.5 mm in diameter can be detected with 64-slice spiral CT using 30 mAs at experimental study, which might be the optimized dose for detecting pulmonary nodules.

Objective To investigate the effect of recombinant human endostatin(rh-Endostatin) combined with transcatheter arterial chemoembolization(TACE) on the growth and metastasis of the implanted hepatic tumor in rabbits.Methods Thirty New Zealand white rabbits were randomly divided into three groups (10 in each group)and VX_2 carcinomas were implanted in the left lobes of the livers. Fourteen days later, a catheter was inserted into the hepatic artery of rabbits with VX2 hepatic tumor and infusion was performed via the hepatic artery using physiological saline (group A), TACE (group B) and rh-Endostatin combined with TACE (group C),respectively. Five weeks later, all ribbits were sacrificed, the body weight and liver weight of animals were assessed, the hepatic index(HI) was calculated, the volume and necrotic area of the implanted tumor were measured. The presence of metastases in the liver, lungs were recorded. Results Five weeks after inoculation, the body weight of all animals decreased, the liver weight increased, His were 10.2±2.8, 8.5±6.1and 6.2±4.4 in groups A, B and C, respectively. The mean volume and necrostic areas of the implanted tumor were (36.2±3.4) cm~3 and (52.0±2.3)% in group A, (23.6±4.5) cm~3 and (63.6±3.5)% in group B, (10.9±5.1) cm~3 and (78.6±4.8)% in group C, respectively. There were statistical significance about tumor volume and necrostic areas of the tumors between group C and group A,B ( P<0.01). The numbers of metastases in the lungs were 50.3±31.3,53.6±35.1 and 16.8±18.4 , and the diameters of metastases in the lungs were (3.6±1.4) mm, (3.8±0.6) mm and (1.2±0.6) mm in groups A, B and C, respectively, the difference between group C versus other groups( P<0.01) was statistically significant. The differences of opportunity, tumor numbers and size of metastases in the liver were statistically significant. (P<0.01).Conclusion Treatment with rh-Endostatin combined with TACE can suppress the growth of tumor and tumor's metastases in lungs inVX2 implanted tumors of rabbits.