Objective To analyze the time-density curve of the small HCCs in the arterial phase and to find out its unique features.Methods All lesions were imaged with single-level serial SCT.The attenuations of the lesion,hepatic artery and hepatic parenchyma were measured.The time-density curve was built with these CT values and their corresponding times.Results The time-density curves of the lesion and liver parenchyma were divided into three kinds:the first kind had two intersects(73%).The first one was seen at the time when the curve of the lesion went up over the one of the parenchyma and the second was seen at the point the curve came down below the parenchyma's.There was no second intersecting point in the second type(19.2%) and the curve of the lesion was below that of the parenchyma in the third (7.7%). Conclusion The initial time of the enhancement of small SHCC is (21.6?6) s.The optimal time of the enhancement of SHCC is (36?8) s.

Background: CT scan of hepatic carcinoma after transarterial embolization with Lipiodol (LP-TAE) will be influenced. A comparative study was made between CT scan and hepatoarteriography in hepatic carcinomas fully filled with Lipiodol after TAE for the purpose of demonstrating the difference. Materials and Methods: 20 cases of hepatic carcinoma fully filled with Lipiodol after TAE 1 to 8 months, confirmed by CT scans. Hepatoarteriography were then done 1 to 14 days afterwards. The demonstration of the original and new foci were thus be compared respec- tively by these methods. Results: The original tumor lesions were all stable on CT scans and new tumor lesions were found in 5 cases. Three features were found in arteriographies of the original tumor lesions: (1) stable, no obvious tumor vessels and stain; (2) tumor vessels and stains confined within the LP accumulated areas; (3) largely increased lesions exceeding the LP accumulated areas; (3)largely increased lesions exceeding the LP accumulated areas. Also other three features were found in new tumor lesion: (1) multiple intrahepatic daughter nodules; (2)small arterioportal shunts; (3) new masses. Conclusion: (1) Although good results had been archieved, but the lesions were not stabe in many of them. Long interval follow-up and TAE were not suitable. (2) Stage-Ⅱ surgical resection should be taken cautiously. (3) New techniques of CT scan and superselective he- patic arteriography with high flow rate should be adopted to improve the accuracy rate of de- monstrating tumor lesion.

Objective To study the clinical value of colorectal carcinoma exa mination by comparison of different postprocessing techniques such as multiplana r reformation(MPR),CT virtual colonoscopy(CTVC), shaded surface display(SSD) a nd Raysum. Methods 64 patients with colorectal carcinoma s underwent volu me scanning using spiral CT. MPR, CTVC, SSD and Raysum images were obtained by u sing 4 different softwares in workstation. All cases were proved by surgical or CC bioptic histology. The results were compared and analyzed according to the circumferential extension, length and pathologic patterns of colorectal carcinoma with MPR, CTVC, SSD and Raysum. Results The correct ion rate of dete rmination the circumferential extension of colorectal carcinoma with MPR, CTVC, SSD and Raysum were 1000%, 828%, 797% and 797%, respectively There wa s signi ficant statistical difference between MPR and CTVC; The accuracy of judging the leng th of carcinoma were 891%, 766%, 953% and 1000%, respectively. There wa s stat istical difference between CTVC and SSD; The accuracy of showing carcinoma patho logi c patterns were 813%, 922%, 719% and 719%, respectively. There was stati stica l difference between CTVC and SSD, too. MPR could correctly determine the circum ferential extension of colorectal carcinoma. In determination the length of carc inoma, Raysum was more accurate than SSD. CTVC could be more helpful in showing carcinoma pathologic patterns. Conclusion There were advantag es and disadvant ages in colorectal carcinoma examination with MPR, CTVC, SSD and Raysum, and the combination could display colorectal carcinoma more completely and comprehensiv ely.

Objective　To optimize the oral contrast media in three-dimensional display of gastric lesions. Methods　41 cases were randomly divided into 3 groups according to different oral contrast media administered: No. 1 air contrast group (n=17), No. 2 fat emulsion group (n=7) and No. 3 positive contrast group (n=25). The 3D CT images were reconstructed using MPR, SSD, RaySum display and virtual endoscopic techniques, and compared with gastric endoscopy and/or conventional barium study.Results　The detectability of gastric lesions using fat emulsion and air contrast was 42.8%(3/7) and 80.0%(20/25), respectively, both were significantly lower than that using positive contrast (100%, 30/30) (χ2=19.22,P＜0.01;χ2=6.60, P＜0.05). The capability of showing the details of stomach lesions was significantly affected by the oral contrast media administered（χ2=17.04，P＜0.01）. Conclusion　It is very important to choose the appropriate oral contrast media for 3D display of gastric lesions in spiral CT, the positive contrast agent is the optimal choice.

Objective　To evaluate the value of gradient-echo chemical shift imaging in detection of lipid-containing abdominal lesions. Methods　35 patients with abdominal lesions were divided into 2 groups according to whether or not they contained lipid. Breath-hold in-phase(IP) and opposed-phase(OP) acquisitions were performed. The demonstration of these lesions on IP and OP was compared. The signal intensity of these lesions on both images was measured. The percentage of signal intensity variation on IP and OP was calculated and statistically analyzed with non-parametric method between the 2 groups. Results　For lesions containing lipid, the signal intensity dropped significantly from IP to OP, with median value of signal intensity variation attaining 37.1%. On the other hand, for lesions not containing lipid, the signal intensity did not change obviously between IP and OP, whose median value of signal intensity variation was 3.3%. The difference between the 2 groups was statistically significant (u=4.56，P<0.01). Conclusion　Gradient-echo chemical shift imaging is an easy and practical way, helpful to detection of lipid component within abdominal lesions.

Objective To improve the diagnostic accuracy of ovarian endometrioma and to discriminate it from other adnexal masses by analyzing its CT manifestations. Methods The CT images of 57 patients with 77 ovarian endometriomas proved by surgery and pathology were studied retrospectively.Results The cysts ranged in diameter from 2 to 14 cm with the mean size of 6.2 cm?5.1 cm. The margins of the cyst were sharp in 39 and ill defined in 38 endometriomas. Thin and thickened walls were found respectively in 40 and 37 of 77 endometriomas. Unilocular, bilocular and multilocular forms were seen respectively in 29(37.7%), 23(29.9%) and 25(32.5%) of 77 endometriomas. Gourd and sister forms were present respectively in 15 and 8 of 23 bilocular cysts, and sister loculi, outer son loculi, inner son loculi, and mixed forms in 10, 9, 1 and 5 of 25 multilocular endometriomas. The density of the cyst fluid varied from 11～65 HU with the mean of 28.5 HU. New hemorrhage inside cyst was found in 6 cysts. Slight or intermediate enhancement of the cyst wall of endometriomas in 42, and significant enhancement in 35 were demonstrated. 54 cysts, 13 cystadenomas with 18 lesions and 4 malignant tumors with 5 lesions were diagnosed by preoperatively by CT. The accurate rate of CT characterization was 71.4%. Conclusion The certain morphologic characteristics of the ovarian endometrioma can be showed by CT in higher extent. It is critical to familiar with these characteristics to improve the diagnostic accuracy, and to avoid misdiagnosis.

Objective To evaluate the clinical effect in patients with primary liver cancer (PLC) well filled with Lipiodol after transcatheter arterial chemoembolization (TACE). Methods 144 patients with PLC well filled with lipiodol after TACE were analysed retrospectively, and the survival rates were calculated by Kaplan Meier method. Results The overall cumulative survival rates for 1,2,3,4 and 5 year were 85.0%, 63.7%, 51.7%, 33.9% and 16.9% respectively. Significant differences were found for 1,2,3 and 4 year survival rates and that of 400 patients with PLC treated by TACE reported previously by our department ( P

Purpose:To evaluate the role of CT in diagnosing local recurrence after surgery of gastric carcinoma. Methods:Two groups of 51 patients after surgery of gastric carcinoma were prospectively studied by means of CT performed with the water as oral contrast,hypotonic agent and dynamic or spiral CT technique. 15 patients proved to be without local recurrence measured the thickness and observed the CT findings of anastomosis stoma ,36 patients proved to have local recurrence ,those patients included male 21 and female 15.Results:90.19%(46/51)anastomosis stoma was clearly demonstrated ,and 32 lesions was detected and confirmed the diagnosis in 29 of 32 cases . The CT findings of local recurrence after gastric resection for gastric cancer were irregular gastric wall thickening ( n =14),local mass ( n =6) and mixed lesions ( n =9).Conclusions:Using the optimal technique can improve the detectability and accuracy of CT for diagnosing the local recurrence after surgery for gastric carcinoma.

Objective To investigate CT and MRI manifestations of uveal melanoma as well as their diagnostic value.Methods 33 cases of uveal melanoma proved by operation and pathology were studied retrospectively.CT and MRI scanning were performed in 15 and 18 patients respectively.Results The round occupying lesions within eyeball were the characteristic imaging finding of uveal melanomas, most of them were found in the location of choroid membrane. These lesions appeared as homogenous density on CT and short T 1 and short T 2 intensity on MRI. MRI was superior to CT because it could provide more accurate information such as location, shape,extension,and differentiation of the complication (retina detachment) from lesion itself. The preoperation diagnostic accuracy of CT was 53% compared with that of 88% of MRI. Conclusion MRI is the optimal examination method in confirming suspected uveal melanoma.

5 mm) in 4 cases, and polypoid mass in 3.[WT5”HZ] Conclusion[WT5”BZ] CT is a new non invasive technique, evaluable in the diagnosis of chololedochal cyst complicated with carcinoma. [WT5”HZ]