慢性侵袭性真菌性鼻窦炎的CT和MRI表现及诊断价值分析

目的:探讨慢性侵袭性真菌性鼻窦炎的CT、MRI表现及其诊断价值。方法:选取50例确诊为慢性侵袭性真菌性鼻窦炎的患者进行研究,对其分别进行CT、MRI扫描,计算CT、MRI对慢性侵袭性真菌性鼻窦炎的阳性检出率。结果:CT的阳性检出率为94%,MRI的阳性检出率为96%,与病理诊断结果进行比较,差异均无统计学意义(P>0.05)。结论:慢性侵袭性真菌性鼻窦炎应用CT、MRI的诊断准确性均较高,可在临床诊断中推广使用。

Preoperative Localization of Insulinoma by Intra-arterial Spiral CT

Objective To evaluate the value of intra-arterial dynamic spiral CT on preoperative localization of insulinoma. Methods Two patients with insulinoma proved by operative pathology were preoperatively localized by intra-arterial dynamic spiral CT. Results In intra-arterial spiral CT, two small insulinomas (1.5–2.0 cm in diameter) demonstrated as a significantly high dense nodule 20 s later after initiation of injection of contrast medium. The course of high density lasted nearly 4 min. Conclusion Intra-arterial dynamic spiral CT could clearly detect small insulinoma, and might be one of most effective preoperative localization methods for small insulinoma. Key words insulinoma - anteriography - CT

CT diagnosis of 52 patients with lymphoma in abdominal lymph nodes

AIM： To assess CT manifestations and its diagnostic value for lymphoma in the abdominal lymph nodes （LALN）.METHODS： CT findings in 52 cases of LALN proved by surgery or biopsy, including Hodgkin＇s disease （HD） in 16 cases and non-Hodgkin＇s lymphoma （NHL） in 36 cases, were retrospectively analyzed.RESULTS： （1） CT manifestations based on distribution of the lesions of LALN： Solitary mass type was found in 10 cases, including solitary, round, uniform-density, enlarged lymph nodes in 3 cases; and multiple, enlarged lymph nodes fusing into singular Iobular mass in 7 cases. Thirty-feur cases of multiple-nodular type showed multiple, round, enlarged lymph nodes with uniform density and clear margins. Vessels-embedded signs, including mesenteric vessels, renal vessels, abdominal aorta or inferior vena cava, were seen in 6 cases, and duodenum-embedded signs were seen in 2 cases. Eight cases of diffuse type showed characteristic ＂cobblestone signs＂. （2） CT manifestations correlated with pathological type： CT manifestations of 12 cases of HD were different from those of 40 cases of NHL in distribution, size, quantity and fused lesion of enlarged lymph nodes. （3） Twenty-eight cases of 52 patients were accompanied with extra-nodal lymphoma in the abdomen, especially gastrointestinal lymphoma, which had characteristic CT findings. （4） In follow-up examinations, CT images showed uniform, heterogeneous or rim enhancement in 15 cases, and occasional calcifications accompanied with reduction of the lesion size and quantity in 12 cases, whereas the lesions disappeared in 3 cases after treatment.CONCLUSION： CT images show many characteristic manifestations valuable for qualitative diagnosis of LALN, and it is also helpful for pathological classification of LALN and therapeutic evaluation in follow-up of patients.

Value of CT in the diagnosis and management of gallstone ileus

AIM:To retrospectively establish the diagnostic criteria of gallstone ileus on CT, and to prospectively apply these criteria to determine the diagnostic accuracy of CT to confirm or exclude gallstone ileus in patients who presented with acute small bowel obstruction (SBO). Another purpose was to ascertain whether the size of ectopic gallstones would affect treatment strategy. METHODS: Fourteen CT scans in cases of proved gallstone ileus were evaluated retrospectively by two radiologists for the presence or absence of previously reported CT findings to establish the diagnostic criteria. These criteria were applied in a prospective contrast enhanced CT study of 165 patients with acute SBO, which included those 14 cases of gallstone ileus. The hard copy images of 165 CT studies were reviewed by a different group of two radiologists but without previous knowledge of the patient's final diagnosis. All CT data were further analyzed to determine the diagnostic accuracy of gallstone ileus when using CT in prospective evaluation of acute SBO. The size of ectopic gallstone on CT was correlated with the clinical course. RESULTS: The diagnostic criteria of gallstone ileus on CT were established retrospectively, which included: (1) SBO; (2) ectopic gallstone; either rim-calcified or total-calcified; (3) abnormal gall bladder with complete air collection, presence of air-fluid level, or fluid accumulation with irregular wall. Prospectively, CT confirmed the diagnosis in 13 cases of gallstone ileus with these three criteria. Only one false negative case could be identified. The remaining 151 patients are true negative cases and no false positive case could be disclosed. The overall sensitivity, specificity and accuracy of CT in diagnosing gallstone ileus were 93%, 100%; and 99%, respectively. Surgical exploration was performed in 13 patients of gallstone ileus with ectopic stones sized larger than 3 cm. One patient recovered uneventfully following conservative treatment with an ectopic stone sized 2 cm in the long axis. CONCLUSION: Contrast enhanced CT imaging offered crucial evidence not only for the diagnosis of gallstone ileus but also for decision making in management strategy.

ROC analysis of CT hemodynamic in the diagnosis of breast cancer

Objective:The aim of this study was evaluate the diagnostic value of computed tomography(CT) perfusion in breast cancer by the method of receiver operator characteristic curve(ROC) analysis.Methods:Eighty-one cases with breast masses found by health examination or mammography were scanned by multi-slice spiral CT(MSCT) perfusion and hemodynamic parameters of blood flow(BF), mean transit time(MTT) and blood volume(BV) were calculated by deconvolution arithmetic.According to the pathologic results, two groups, benign and malignant were classified and statistical analysis were performed between them.The ROC characteristics of BF, MTT, BV were compared for each and the diagnostic value of the hemodynamic parameters were confirmed.Results:In the malignant group, BF was(0.735 ± 0.440) mL/min/mL, MTT was(22.771 ± 7.647) s and BV was 0.234 ± 0.082.In the benign group, BF was(0.466 ± 0.527) mL/min/mL, MTT was(26.712 ± 12.934) s and BV was 0.179 ± 0.117.There was a significant difference for BF and BV between the benign and malignant groups.When the hemodynamic parameters were used to discriminate the breast lesions, the area under the ROC curve(AUCROC) of BF was 0.832 ± 0.086, the maximum, while AUCROC of BV was 0.695 ± 0.092.There was no significant statistical difference between BF and BV.AUCROC of MTT was 0.473 ± 0.102, which was minimal.Since the threshold of BF was 0.381 mL/min/mL, the sensitivity was 82.3%, the specificity was 73.2%, the positive likelihood ratio(LR) was 3.071 and the negative LR was 0.242.The threshold of BV was 0.190 with sensitivity 73.3%, specificity 56.5%, positive likelihood ratio 1.685 and negative LR 0.473.Conclusion:BF and BV among CT hemodynamic parameters have certain diagnostic value in breast cancer, but BF or BV can not yet be single index to confirm or deny the diagnosis.

Capability of multidetector CT to diagnose hepatocellular carcinoma-associated arterioportal shunt

AIM: To investigate the capability of multidetector CT (MDCT) to diagnose HCC-associated arterioportal shunt (APS).METHODS: Two hundred and eighty-two patients with HCC received both thin-slice and enhancement MDCT scanning at early hepatic arterial phase, late hepatic arterial phase and portal venous phase, and digital subtract angiography (DSA) examination. Images were analyzed jointly by two experienced radiologists blinded to the opposite examination results, including the existence or not of APS, shunt locations, types and degrees of APS, with or without thrombosis. RESULTS: There were 56 APS associated with HCC, including 48 central, seven peripheral and one mixed, or 42 severe, seven moderate, seven mild APS. Fortyone severe, seven moderate and central APS were all revealed with MDCT and DSA. Seven mild and peripheral APS were all displayed with MDCT; only five of them displayed DSA, two faint shunt APS associated with massive HCC were missed. One mixed APS was demonstrated as severe combined with mild shunt with both MDCT and DSA.CONCLUSION: MDCT could diagnose not only DSA revealed APS, but also missed mild and peripheral APS with DSA due to faint shunt associated with massive HCC, is a simple, effective and noninvasive new technique for diagnosis of HCC-associated APS.

MRI versus 64-row MDCT for diagnosis of hepatocellular carcinoma

AIM： To compare the diagnostic capability of multidetector computed tomography （MDCT） and magnetic resonance imaging （MRI） for the detection of hepatocellular carcinoma （HCC） tumour nodules and their effect on patient management. METHODS： A total of 28 patients （25 male, 3 female, mean age 67 ± 10.8 years） with biopsy-proven HCC were investigated with 64-row MDCT （slice 3 mm native, arterial and portal-venous phase, 120 mL Iomeprol, 4 mL/s, delay by bolus trigger） and MRI （Tlfs fl2d TE/ TR 2.72/129 ms, T2tse TE/TR 102/4000 ms, 5-phase dynamic contrast-enhanced Tlfs fl3d TE/TR 1.56/4.6, Gadolinium-DTPA, slice 4 mm）. Consensus reading of both modalities was used as reference. Tumour nodules were analyzed with respect to number, size, and location. RESULTS： In total, 162 tumour nodules were detected by consensus reading. MRI detected significantly more tumour nodules （159 vs 123, P 〈 0.001） compared to MDCT, with the best sensitivity for early arterial phase MRI. False-negative CT findings included nodules ≤ 5 mm （n = 5）, ≤ 10 mm （n = 17）, ≤ 15 mm （n= 12）,≤20mm（n=4）,andlnodule〉20mm.MRI missed 2 nodules ≤ 10 mm and 1 nodule ≤ 15 mm. On MRI, nodule diameters were greater than on CT （29.2 ≤25.1 mm, range 5-140 mm vs 24.1 ± 22.7 mm, range 4-129 mm, P 〈 0.005）. In 2 patients, MDCT showed only unilobar tumour spread, whereas MRI revealed additional nodules in the contralateral lobe. Detection of these nodules could have changed the therapeutic strategy. CONCLUSION： Contrast-enhanced MRI is superior to 64-row MDCT for the detection of HCC nodules. Patients should be allocated to interventional or operative treatment according to a dedicated MRI-protocol.

Evaluation of spiral CT imaging in the diagnosis of the primary ureteral carcinoma

Objective: To explore the characteristics of the primary ureteral carcinoma (PUC) and discuss the value of spiral CT (SCT) in the diagnosis of PUC. Methods: The SCT findings of the primary ureteral carcinoma in 16 cases were analyzed and compared with the histopathological diagnosis and staging. Results: The transverse diameters of the lesions were 1.0–2.1 cm, and the longitudinal lengths were 1.5–15.2 cm. There were no statistically significant differences (P>0.1) in diam- eters and lengths among the low staging group (pT0–T2) and the high staging group (pT3–T4). The average CT value of the lesions was 43 HU on plain scanning, and 73 HU on CE scanning. The increment was 30 HU. The lesions were clearer on CE scanning. Curved planar reconstruction (CPR) could show the entire course of the urinary tract. Among 6 cases of pT3 stage, CT gave a correct diagnosis in 1 case. For 2 cases of pT4 stage, CT gave correct diagnoses in both cases. Conclusion: The carcinomatous lesions spread along the ureter. The longitudinal length of each lesion is longer than its transverse diameter. Tumor cannot be staged merely according to its diameter and length. CT is difficult to differentiate stage T0–T3, while for stage T4, CT diagnosis is accurate. Contrast enhancement CT scanning has the confirming and differentiating roles. CPR offers direct and easy observing images for clinical doctors.

Value of Multi-slice spiral CT in diagnosis of malignant gastrointestinal stromal tumors

Objective： The aim of this study was to investigate the value of multi-slice spiral CT （MSCT） in the diagnosis of malignant gastrointestinal stromal tumors （GISTs）. Methods： Twenty-seven cases of MSCT images of malignant GIST proved by surgery and pathology were retrospectively analyzed. Both plain and enhanced CT scan was performed and multiplanar reconstruction was made in all cases. Results： The lesions originated from the stomach （n = 11）, small intestine （n = 9）, colon （n = 4）, rectum （n = 1）, and mesentery （n = 2）. The transverse diameters of mass were 4.2-22 cm, the edges clearly （n = 12）, unclearly （n = 15）. The mass were mainly irregular in shape Iobulated （n = 19）. The lesions were mainly heterogeneity on plain scan, moderate to marked enhancement in arterial phase and durative enhanced in venous phase. Cystic necrosis were observed in all the lesions, 9 cases were cystic and solid mixed mass. Hepatic metastases （n = 4）, pulmonary metastasis （n = 1）, lymphatic metastasis （n = 2） were detected. The accuracy rate of MSCT diagnosis for location and pathologic features of GISTs were 85.2% （23/27） and 77.8% （21/27）. Conclusion： Two-phase MSCT examination and axial images combined with multiplanar reconstruction images have important value for diagnosis of malignant GIST.

Total colorectal and terminal ileal duplication presenting as intussusception and intestinal obstruction

Colonic intussusception and gastrointestinal duplication are diseases that arise in young children. The clinical presentation of adult cases of intussusception and enteric duplication is non-specific and thus poses a diagnostic challenge. A computed tomography (CT) scan is recommended in adult cases as the most sensitive diagnostic tool and the pathognomonic finding of outer intussuscepiens and central intussusceptum is diagnostic. A septum of a duplicated colon in a non-intussuscepted segment has been rarely reported in the literature. With advancements in radiological imaging technology and the increased availability of CT scanners, the capacity for a correct pre-operative diagnosis has been significantly enhanced. Our current case report illustrates the importance of considering an uncommon etiology for enteric intussusception and duplication as a differential diagnosis of acute abdomen in an adult patient. Our analyses of this patient also highlight the successful use of CT scanning to make this diagnosis.

The value of MSCT in diagnosis of parotid benign tumor (An analysis of 84 cases)

Objective:The purpose of the study was to assess diagnostic performance of MSCT images in patients with parotid benign tumors and provide useful criteria for the characterization of their various pathological types preoperatively. Methods: Retrospectively analyzed clinical and imaging characteristics of 84 cases of pathologically confirmed primary parotid benign tumors. MSCT plain-scan and enhanced-scan were performed in all cases. After injection of 50 mL contrast material at a rate of 3.5 mL/s,spiral CT scans were obtained at arterial and venous phases with scanning delay of 30 s and 75 s,respectively. The attenuation change and enhancement patterns in the tumors were assessed. Quantitatively assess the increased CT number of the tumors in different enhanced-phases compared with the plain-scan and the ratio of increased CT number at venous phase scanning to that at arterial phase scanning also was calculated. Results:In all of 84 cases,40 cases were solitary pleomorphic adenomas,29 cases were adenolyphomas,6 cases were multiple tumors,2 cases were bilateral,15 cases were Basal cell tumor,and one of them had two small lesions. The diameter was 1–5 cm in most of cases,whose margin was smooth and clear,cystic changes in some cases. At two-phase scans,pleomorphic adenomas showed a pattern of slight enhancement and venous enhancement,adenolymphomas showed a pattern of strong enhancement at arterial phase scanning with a decrease at venous phase scanning,basal cell tumor showed a pattern of persistent strong enhancement with commonly significant cystic areas. The ratio of increased CT number was significant different between adenolymphomas and other pathological types. Conclusion: The evaluation of enhancement patterns at two-phase enhanced-scan MSCT is helpful in the differential diagnosis of parotid gland benign tumors.

Role of SPECT/CT in diagnosis of hepatic hemangiomas

AIM: To investigate the role of SPECT/CT in the diagnosis of hepatic hemangiomas whose anatomical positions are not ideal, situated adjacent to the heart, the inferior cava,hepatic vessels or abdominal aorta, etc.METHODS: The hepatic perfusion, blood pool, and fusion imaging were carried out using SPECT/CT in 54 patients,who were suspected for hepatic hemangiomas. When the anatomical positions were not ideal, the diagnosis was difficult by SPECT only. So the information of computed tomography (CT) was applied to help in diagnosing. The results were recorded as hemangiomas or not.RESULTS: Of the 54 patients, 31 patients were diagnosed as suffering from hepatic hemangiomas. The anatomical positions of eight patients' hepatic hemangiomas (25.81%)were not ideal. Among these lesions of the eight patients,three patients' hepatic lesions were located near to the abdominal aorta, one to the heart, and four to the inferior cava. In addition, six abnormal radioactivity accumulation regions, adjacent to the heart and inferior cava, with the help of CT, were confirmed to be the imaging of inferior cava other than hepatic hemangiomas.CONCLUSION: When the anatomical positions of hepatic hemangiomas are not good enough for diagnosis, the fusion imaging of SPECT/CT is a simple and efficient method for differential diagnosis.

Comparison of diagnostic value of PET using 18- fluoro-2-deoxyglucose, CT and MR1 in detecting skull base invasion of nasopharyngeal carcinomas

Objective： We compared positron emission tomography （PET） using 18-fluoro-2-deoxyglucose （FDG）, enhanced computed tomography （CT） and magnetic resonance imaging （MRI） in detecting skull base invasion of nasopharyngeal carcinomas （NPC） and to evaluate the value of these three methods in determining the existence of skull base invasion of nasopharyngeal carcinomas. Methods： The images of enhanced CT, MRI and PET-CT scans, performed at intervals -〈 20 days on 57 NPC patients from July 2004 to February 2007, were selected and reviewed. The endpoints of the comparison were sensitivity, specificity, accuracy, positive predictive value （PPV） and negative predictive value （NPV） of Enhanced CT, MRI and PET-CT, based on histopathologic findings or clinical imaging follow-up for at least 6 months. Results： For detecting skull base invasion of NPC, the sensitivity of enhanced CT, MRI and PET-CT were 68.18%, 84.09%, 97.67% respectively; speci- ficity were 76.92%, 69.23%, 57.14% respectively; accuracy were 70.18%, 80.7%, 87.72% respectively; PPV were 90.9%, 90.24%, 87.5% respectively; NPV were 41.67%, 56.25%, 88.89% respectively. Conclusion： PET-CT has obvious advantages in sensitivity over CT （P 〈 0.05） and MRI, better than the two methods in accuracy and NPV and may be more valuable for new patients in detecting skull base invasion of NPC patients.

The diagnostic value of 3D spiral CT imaging of cholangiopancreatic ducts on obstructive jaundice

Objective: Computerized tomography (CT) plays an important role in the diagnosis of diseases of biliary tract. Recently, three dimensions (3D) spiral CT imaging has been used in surgical diseases gradually. This study was designed to evaluate the diagnostic value of 3D spiral CT imaging of cholangiopancreatic ducts on obstructive jaundice. Methods: Thirty patients with obstructive jaundice had received B-mode ultrasonography, CT, percutaneous transhepatic cholangiography (PTC) or endoscopic retrograde cholangiopancreatography (ERCP), and 3D spiral CT imaging of cholangiopancreatic ducts preoperatively. Then the diagnose accordance rate of these examinational methods were compared after operations. Results: The diagnose accordance rate of 3D spiral CT imaging of cholangiopancreatic ducts was higher than those of B-mode ultrasonography, CT, or single PTC or ERCP, which showed clear images of bile duct tree and pathological changes. As to malignant obstructive jaundice, this examinational technique could clearly display the adjacent relationship between tumor and liver tissue, biliary ducts, blood vessels, and intrahepatic metastases. Conclusion: 3D spiral CT imaging of cholangiopancreatic ducts has significant value for obstructive diseases of biliary ducts, which provides effective evidence for the feasibility of tumor-resection and surgical options.

Utility of fusion CT-PET in the diagnosis of small pancreatic carcinoma

Pancreatic carcinoma has a poor prognosis and early detection is essential for potentially curative resection. Despite the wide array of diagnostic tools, preoperative detection of small pancreatic carcinomas remains difficult. We report a case of small pancreatic carcinoma of the head of pancreas with indeterminate findings on US, ERCP, MRI and EUS which was successfully diagnosed via fusion CT-PET. This case illustrates the utility of CT-PET in the diagnosis of patients with small pancreatic carcinoma with equivocal findings on conventional diagnostic modalities.

Diagnosis of carotid body tumor by digital subtraction angiography

Objective: To make a further understanding of the features of the carotid body tumor (CBT) by digital subtraction angiography (DSA) so as to explore the clinical value of DSA diagnosis and interventional therapy for CBT. Methods: DSA data from 12 cases of CBT were analyzed retrospectively. A consensus interpretation of the DSA appearances in all of the patients was reached after dynamic observation by 2 experienced radiologists in a double blind manner. Results: Definite diagnosis in all cases could be made by DSA. The DSA features of the CBT included bigger bifurcation angles of the internal and external carotid arteries, displacement of internal and external carotid arteries, CBT supplied by external carotid arteries in most cases and the significant increase of tumor blood vessels in bifurcation. Invasion of internal or external carotid arteries was found in 6 cases. Smaller stained area of the tumor and significantly reduced intraoperative bleeding were found after embolization of the supplying arteria in 2 cases. Conclusion: DSA is the effective method for the diagnosis and preoperative assessment of CBT. Preoperative embolization of CBT may contribute to the reduced intraoperative bleeding.

Clinical significance of magnetic resonance cholangiopancreatography utilizing half-Fourier acquisition single-shot fast spin-echo in diagnosing bile duct diseases

Objective: To investigate the clinical significance of magnetic resonance cholangiopancreatography (MRCP) utilizing half-Fourier acquisition single-shot fast spin-echo (HASTE) in the diagnosis of bile duct diseases. Methods: Forty-three patients with obstructive jaundice and 4 without were enrolled in this study. The underlying diseases included bile duct calculi ( 13 cases) , chronic cholangitis ( 14 cases) malignant tumors (18 cases) and congenital biliary cysts (2 cases). All patients underwent examinations with magnetic resonance imaging (MRI) and MRCP, and 39 were also examined with B-type ultrasonography, 33 with CT and 25 with ERCP and PTC. Three-dimensional image reconstruction was performed using volume-rendered technique ( VRE) on the basis of the data obtained by MRCP. Results: The biliary calculi were displayed as circular filling defects in MRCP images, with the proximal end of dilated bile duct taking the form of the mouth of a cup. The bile duct of patients with chronic cholangitis showed distal end dilation and thinner proximal end without discontinuity. Interception of the bile ducts was most frequent (72. 2% ) in cases of malignant bile duct obstruction, in which the ducts may also be mastoid or resembling rat tails. 72. 2% of the cases had severe dilation of the bile ducts, which occur in only 16. 0% of the benign cases, with significant difference between them (P <0. 01) . In images of intrahepatic biliary cyst, intrahepatic duct dilated in the shape of a bursa in connection with the duct. By MRCP, 20 malignant obstructions of the bile ducts were identified with 2 misdiagnoses, and in 25 cases of benign obstructions identified by MRCP, only 1 misdiagnoses occurred. Thus MRCP had the sensitivity, specificity and accuracy of 90.0% , 96.3% and 93.6% respectively in discriminating benign and malignant diseases of the bile ducts, showing a total diagnostic accuracy of 94. 0% that was similar to that of ERCP (92.0% ) but significantly higher than those of both CT (75. 0% ) and B-type ultrasonic examination (74. 0% ). Conclusion: In diagnosing obstructive jaundice, HASTE MRCP is similar to ERCP but better than CT and B-type ultrasonography , with the merits of fast imaging and high resolution as an ideal sequence for MRCP imaging.

A New Method of CT Medical Images Contrast Enhancement

A new method of contrast enhancement is proposed in the paper using multiscale edge representation of images, and is applied to the field of CT medical image processing. Comparing to the traditional Window technique, our method is adaptive and meets the demand of radiology clinics more better. The clinical experiment results show the practicality and the potential applied value of our method in the field of CT medical images contrast enhancement.

Analysis of 96 cases of solitary pulmonary nodule diagnosed by MSCT

Objective:The aim of this study was to explore the diagnostic value of multi-slice computer tomography(MSCT) in solitary pulmonary nodule(SPN).Methods:Contrastive analysis of the differences of CT signs between benign and malignant SPN.Results:The typical sign of pleural indentation was a reliable sign for lung cancers.Vacuole sign suggested lung cancer highly.Blood vessels cluster involving the vein alone had big opportunity to lung cancer.Type I tumor-bronchial relation was the most common relation in lung cancers.Type V tumor–bronchial relation was the most common relation in benign SPN.Conclusion:MSCT had a very high diagnostic value in SPN.

Diagnostic Value of CT Colonography in Colorectal Carcinoma

OBJECTIVE To investigate the value of CT colonography （CTC） in diagnosis and preoperative staging of colorectal carcinoma.METHODS CTC was performed on 33 patients who were suspected of having colorectal carcinoma. The results of CTC were compared with those of a pathological examination.RESULTS Among the 22 patients who were diagnosed with colorectal carcinoma by CTC, 20 cases were confirmed by pathology. The diagnostic sensitivity and specificity were 100% （20/20） and 84.6% （11/13） respec- tively. The accuracy of showing carcinoma pathologic patterns was 90% （18/20）. The sensitivity and specificity were both 100% in the mass type; 77.8% and 100% in the infiltrating type; 100% and 85.7% in the ulcerated type. The accuracy of staging Dukes＇ carcinbma was 75%. The sensitivity and specificity were 100% and 94.1% for Dukes＇A; 80% and 73.3% for Dukes＇ B： 60% and 100% in Dukes＇ C： 71.4% and 100% for Dukes＇ D.CONCLUSION CTC produces a high success rate and provides considerable diagnostic information for both an accurate diagnosis of colorectal carcinoma and staging before operation,