AIM： To evaluate the sensitivity and specificity of MR colonography （MRC） and CT performance in detecting colon lesions, and to compare their sensitivity and specificity with that of conventional colonoscopy. METH...AIM： To evaluate the sensitivity and specificity of MR colonography （MRC） and CT performance in detecting colon lesions, and to compare their sensitivity and specificity with that of conventional colonoscopy. METHODS： Forty-two patients suspected of having colonic lesions, because of rectal bleeding, positive fecal occult blood test results or altered bowel habits, underwent the examinations. After insertion of a rectal tube, the colon was filled with 1000-1500 mL of a mixture of 9 g/L NaCI solution, 15-20 mL of 0.5 mmol/L gadopentetate dimeglumine and 100 mL of iodinized contrast material. Once colonic distension was achieved, three-dimensional gradient-echo （3D-GRE） sequences for MR colonography and complementary MR images were taken in all cases. Immediately after MR colonography, abdominal CT images were taken by spiral CT in the axial and supine position. Then all patients were examined by conventional colonoscopy （CC）. RESULTS： The sensitivity and specificity of MRC for colon pathologies were 96.4% and 100%, respectively. The percentage of correct diagnosis by MRC was 97.6%. The sensitivity and specificity of CT for colon pathologies were 92.8%, 100%, respectively. The percentage of correct diagnosis by CT was 95.2%. CONCLUSION： In detecting colon lesions, MRC achieved a diagnostic accuracy similar to CC. However, MRC is minimally invasive, with no need for sedation or analgesics during investigation. There is a lower percentage of perforation risk, and all colon segments can be evaluated due to multi-sectional imaging availability; intramural, extra-intestinal components of colonic lesions, metastasis and any additional lesions can be evaluated easily. MRC and CT colonography are new radiological techniques that promise to be highly sensitive in the detection of colorectal mass and inflammatory bowel lesions.展开更多
AIM: To investigate the correlation between microvessel density and spiral CT perfusion imaging in colorectal carcinoma. METHODS: Thirty-seven patients, with histologically proven colorectal carcinoma, underwent water...AIM: To investigate the correlation between microvessel density and spiral CT perfusion imaging in colorectal carcinoma. METHODS: Thirty-seven patients, with histologically proven colorectal carcinoma, underwent water enema spiral CT scan. The largest axial surface of the primary tumor was searched on unenhanced spiral CT images. At this level, the enhanced dynamic scan series was acquired. Time-density curves (TDC) were created from the region of interest drawn over the tumor, target artery by Toshiba Xpress/SX spiral CT with perfusion functional software. Then the perfusion was calculated. Microvessel density (MVD) was evaluated using immunohistochemical staining of surgical specimens with anti-CD34, and then MVD was correlated with perfusion. RESULTS: MVD of colorectal carcinomas was 33.11-173.44, mean 87.28, and perfusion was 15.60-64.80 mL/min/ 100 g, mean 39.74 mL/min/100 g. MVD and perfusion were not associated with invasive depth, metastasis and disease stage, and they all decreased with increasing Dukes' stage, but no significant correlation was found between them (r=0.18, P=0.29). CONCLUSION: There is no significant correlation between MVD and perfusion. Neovascularizaton and perfusion are highly presented in early colorectal carcinoma. CT perfusion imaging may be more suited for assessing tumorigenesis in colorectal carcinoma than histological MVD technique.展开更多
A primary benign schwannoma of the liver is extremely rare and is difficult to preoperatively discriminate from a malignant tumor.We compared the imaging and pathological findings,and examined the possibility of preop...A primary benign schwannoma of the liver is extremely rare and is difficult to preoperatively discriminate from a malignant tumor.We compared the imaging and pathological findings,and examined the possibility of preoperatively diagnosing a benign liver schwannoma.A 72-year-old woman was admitted to our hospital because of a 4.6-cm mass in the liver.A malignant tumor was suspected,and a right hepatectomy was performed.After this,the diagnosis of a primary benign schwannoma of the liver was made through pathological examination.Contrast-enhanced ultrasonography(CEUS) with Sonazoid showed minute blood flows into the septum and solid areas of the tumor in the vascular phase;most likely due to increased arterial flow associated with infiltration of chronic inflammatory cells.In the postvascular phase,CEUS showed contrast defect of cystic areas and delayed enhancement of solid areas;most likely due to aggregation of siderophores.Because discriminating between a benign and malignant schwannoma of the liver is difficult,surgery is generally recommended.However,the two key findings from CEUS may be useful in discriminating ancient schwannoma by recognizing the hemorrhage involved in the secondary degeneration and aggregation of siderophores.展开更多
Objective: To improve the qualitative diagnosis of peripheral nerve sheath tumors by computed tomography (CT). Methods: CT findings of 64 cases of pathologically confirmed nerve sheath tumors were compared with the pa...Objective: To improve the qualitative diagnosis of peripheral nerve sheath tumors by computed tomography (CT). Methods: CT findings of 64 cases of pathologically confirmed nerve sheath tumors were compared with the pathological findings of the tumors. Results: Low density of the tumors shown in plain CT images was related to dominating reticular structure in the tumor as found pathologically. Tumors with intact capsule found by pathological findings were shown with smooth margin in CT images. Inhomogeneous density and enhancement of the tumors in CT images was related to tumor necrosis, liquefaction and cystic degeneration, and inhomogeneous enhancement also involved the reticular structure. Conclusion: Nerve sheath tumors are characterized by distribution along the nerves, lower density than that of muscles in plain CT images, and inhomogeneous enhancement in enhanced CT, which can help differentiate nerve sheath tumors from other soft tissue tumors. When nerve sheath tumors lack distinctive CT features, the diagnoses have to depend on their pathological findings.展开更多
OBJECTIVE To explore the MR characteristics following lipiodol retention in rabbit liver and to evaluate the sensitivity of CT （CT value 〉400 HU） and MR in displaying the hepatic degeneration and necrosis following...OBJECTIVE To explore the MR characteristics following lipiodol retention in rabbit liver and to evaluate the sensitivity of CT （CT value 〉400 HU） and MR in displaying the hepatic degeneration and necrosis following embolization. METHODS Thirty-two rabbits were randomly divided into 3 groups. In the control group （n=8）, 2 ml of normal saline was injected into the right branch of the portal vein. In the first experimental group（n= 12）, 4 ml of lipiodol emulsion was injected into the main portal vein. In the second experimental group （n= 12）, 2 ml of lipiodol emulsion was injected into the right branch of the portal vein. CT and MR images were obtained before and after surgery in each group. The histopathologic condition was determined for all liver tissue specimens. RESULTS In the control group, CT and MR did not show any significant changes in the livers after surgery. After the operations in the experimental groups, the regional CT attenuation was 601±101 HU in the largest slice, which had no abnormal signals on T1Wl and T2Wl. In the first group, histologic examinations showed there were concentrated lipiodol droplets around the portal areas. In the second group, serious degeneration and necrosis in the right hepatic lobe occurred in 9 rabbits. T1Wl displayed homogenous or non-homogenous low signals and T2Wl mainly displayed a high signal. However, these pathologic changes did not appear on CT scanning due to high attenuation of the lipiodol. CONCLUSION There were no remarkable hepatic changes on MR in rabbits following good retention of the formulated lipiodol emulsion mixture of lipiodol and urografin（CT value 〉 400 HU）. MR displayed serious degeneration and necrosis of the liver following embolization.展开更多
OBJECTIVE To assess the accuracy of multi-slice spiral CT （MSCT） with imaging reconstruction in judging central pulmonary vascular involvement from central lung cancer, and to explore its ability to predict the rese...OBJECTIVE To assess the accuracy of multi-slice spiral CT （MSCT） with imaging reconstruction in judging central pulmonary vascular involvement from central lung cancer, and to explore its ability to predict the resectability of lung cancer. METHODS MSCTs were conducted on 48 patients who were diagnosed preoperatively with central lung cancer. Images of pulmonary arteries and veins that might affect Iobectomy or pneumonectomy were reconstructed by means of imaging processing techniques. Then the relationship of the tumor to the vessels was assessed prospectively on both axial CT images and axial CT images plus reconstructed images（CT-RI） in comparison to subsequent pathologic and surgical findings. RESULTS MSCTs were obtained on all 48 patients whom 42 underwent thoracotomy, Iobectomy or pneumonectomy. Compared with the axial CT images, CT-RI was more accurate in judging the relationship of the central pulmonary vessels to the tumor based on subsequent pathologic 78 vessels studied and surgical findings （186 vessels studied）（0.01 〈P〈0.05）. The sensitivity and positive predictive value of unresectability of the vessels were all remarkably higher with CT-RI （P〈0.01）. CONCLUSION MSCT with imaging reconstruction can improve the recognition of neoplastic invasion of central pulmonary vessels. It can be used to predict preoperatively the resectability of central lung cancer and to plan surgery.展开更多
Angiolipoma, a common benign tumor mostly seen in the subcutaneous tissue, is a rare pathological condition in the gastrointestinal tract that is usually diagnosed postoperatively. In this case report, an angiolipoma ...Angiolipoma, a common benign tumor mostly seen in the subcutaneous tissue, is a rare pathological condition in the gastrointestinal tract that is usually diagnosed postoperatively. In this case report, an angiolipoma was diagnosed preoperatively by imaging （including CT scans, abdominal echo, barium enema, and colonoscopy）. This pathology was confirmed postoperatively. Computed tomography scan, abdominal echo, and barium enema images were presented.展开更多
文摘AIM： To evaluate the sensitivity and specificity of MR colonography （MRC） and CT performance in detecting colon lesions, and to compare their sensitivity and specificity with that of conventional colonoscopy. METHODS： Forty-two patients suspected of having colonic lesions, because of rectal bleeding, positive fecal occult blood test results or altered bowel habits, underwent the examinations. After insertion of a rectal tube, the colon was filled with 1000-1500 mL of a mixture of 9 g/L NaCI solution, 15-20 mL of 0.5 mmol/L gadopentetate dimeglumine and 100 mL of iodinized contrast material. Once colonic distension was achieved, three-dimensional gradient-echo （3D-GRE） sequences for MR colonography and complementary MR images were taken in all cases. Immediately after MR colonography, abdominal CT images were taken by spiral CT in the axial and supine position. Then all patients were examined by conventional colonoscopy （CC）. RESULTS： The sensitivity and specificity of MRC for colon pathologies were 96.4% and 100%, respectively. The percentage of correct diagnosis by MRC was 97.6%. The sensitivity and specificity of CT for colon pathologies were 92.8%, 100%, respectively. The percentage of correct diagnosis by CT was 95.2%. CONCLUSION： In detecting colon lesions, MRC achieved a diagnostic accuracy similar to CC. However, MRC is minimally invasive, with no need for sedation or analgesics during investigation. There is a lower percentage of perforation risk, and all colon segments can be evaluated due to multi-sectional imaging availability; intramural, extra-intestinal components of colonic lesions, metastasis and any additional lesions can be evaluated easily. MRC and CT colonography are new radiological techniques that promise to be highly sensitive in the detection of colorectal mass and inflammatory bowel lesions.
基金Supported by the Medical Science Foundation of Guangdong Province, No. A2002185
文摘AIM: To investigate the correlation between microvessel density and spiral CT perfusion imaging in colorectal carcinoma. METHODS: Thirty-seven patients, with histologically proven colorectal carcinoma, underwent water enema spiral CT scan. The largest axial surface of the primary tumor was searched on unenhanced spiral CT images. At this level, the enhanced dynamic scan series was acquired. Time-density curves (TDC) were created from the region of interest drawn over the tumor, target artery by Toshiba Xpress/SX spiral CT with perfusion functional software. Then the perfusion was calculated. Microvessel density (MVD) was evaluated using immunohistochemical staining of surgical specimens with anti-CD34, and then MVD was correlated with perfusion. RESULTS: MVD of colorectal carcinomas was 33.11-173.44, mean 87.28, and perfusion was 15.60-64.80 mL/min/ 100 g, mean 39.74 mL/min/100 g. MVD and perfusion were not associated with invasive depth, metastasis and disease stage, and they all decreased with increasing Dukes' stage, but no significant correlation was found between them (r=0.18, P=0.29). CONCLUSION: There is no significant correlation between MVD and perfusion. Neovascularizaton and perfusion are highly presented in early colorectal carcinoma. CT perfusion imaging may be more suited for assessing tumorigenesis in colorectal carcinoma than histological MVD technique.
文摘A primary benign schwannoma of the liver is extremely rare and is difficult to preoperatively discriminate from a malignant tumor.We compared the imaging and pathological findings,and examined the possibility of preoperatively diagnosing a benign liver schwannoma.A 72-year-old woman was admitted to our hospital because of a 4.6-cm mass in the liver.A malignant tumor was suspected,and a right hepatectomy was performed.After this,the diagnosis of a primary benign schwannoma of the liver was made through pathological examination.Contrast-enhanced ultrasonography(CEUS) with Sonazoid showed minute blood flows into the septum and solid areas of the tumor in the vascular phase;most likely due to increased arterial flow associated with infiltration of chronic inflammatory cells.In the postvascular phase,CEUS showed contrast defect of cystic areas and delayed enhancement of solid areas;most likely due to aggregation of siderophores.Because discriminating between a benign and malignant schwannoma of the liver is difficult,surgery is generally recommended.However,the two key findings from CEUS may be useful in discriminating ancient schwannoma by recognizing the hemorrhage involved in the secondary degeneration and aggregation of siderophores.
文摘Objective: To improve the qualitative diagnosis of peripheral nerve sheath tumors by computed tomography (CT). Methods: CT findings of 64 cases of pathologically confirmed nerve sheath tumors were compared with the pathological findings of the tumors. Results: Low density of the tumors shown in plain CT images was related to dominating reticular structure in the tumor as found pathologically. Tumors with intact capsule found by pathological findings were shown with smooth margin in CT images. Inhomogeneous density and enhancement of the tumors in CT images was related to tumor necrosis, liquefaction and cystic degeneration, and inhomogeneous enhancement also involved the reticular structure. Conclusion: Nerve sheath tumors are characterized by distribution along the nerves, lower density than that of muscles in plain CT images, and inhomogeneous enhancement in enhanced CT, which can help differentiate nerve sheath tumors from other soft tissue tumors. When nerve sheath tumors lack distinctive CT features, the diagnoses have to depend on their pathological findings.
文摘OBJECTIVE To explore the MR characteristics following lipiodol retention in rabbit liver and to evaluate the sensitivity of CT （CT value 〉400 HU） and MR in displaying the hepatic degeneration and necrosis following embolization. METHODS Thirty-two rabbits were randomly divided into 3 groups. In the control group （n=8）, 2 ml of normal saline was injected into the right branch of the portal vein. In the first experimental group（n= 12）, 4 ml of lipiodol emulsion was injected into the main portal vein. In the second experimental group （n= 12）, 2 ml of lipiodol emulsion was injected into the right branch of the portal vein. CT and MR images were obtained before and after surgery in each group. The histopathologic condition was determined for all liver tissue specimens. RESULTS In the control group, CT and MR did not show any significant changes in the livers after surgery. After the operations in the experimental groups, the regional CT attenuation was 601±101 HU in the largest slice, which had no abnormal signals on T1Wl and T2Wl. In the first group, histologic examinations showed there were concentrated lipiodol droplets around the portal areas. In the second group, serious degeneration and necrosis in the right hepatic lobe occurred in 9 rabbits. T1Wl displayed homogenous or non-homogenous low signals and T2Wl mainly displayed a high signal. However, these pathologic changes did not appear on CT scanning due to high attenuation of the lipiodol. CONCLUSION There were no remarkable hepatic changes on MR in rabbits following good retention of the formulated lipiodol emulsion mixture of lipiodol and urografin（CT value 〉 400 HU）. MR displayed serious degeneration and necrosis of the liver following embolization.
文摘OBJECTIVE To assess the accuracy of multi-slice spiral CT （MSCT） with imaging reconstruction in judging central pulmonary vascular involvement from central lung cancer, and to explore its ability to predict the resectability of lung cancer. METHODS MSCTs were conducted on 48 patients who were diagnosed preoperatively with central lung cancer. Images of pulmonary arteries and veins that might affect Iobectomy or pneumonectomy were reconstructed by means of imaging processing techniques. Then the relationship of the tumor to the vessels was assessed prospectively on both axial CT images and axial CT images plus reconstructed images（CT-RI） in comparison to subsequent pathologic and surgical findings. RESULTS MSCTs were obtained on all 48 patients whom 42 underwent thoracotomy, Iobectomy or pneumonectomy. Compared with the axial CT images, CT-RI was more accurate in judging the relationship of the central pulmonary vessels to the tumor based on subsequent pathologic 78 vessels studied and surgical findings （186 vessels studied）（0.01 〈P〈0.05）. The sensitivity and positive predictive value of unresectability of the vessels were all remarkably higher with CT-RI （P〈0.01）. CONCLUSION MSCT with imaging reconstruction can improve the recognition of neoplastic invasion of central pulmonary vessels. It can be used to predict preoperatively the resectability of central lung cancer and to plan surgery.
文摘Angiolipoma, a common benign tumor mostly seen in the subcutaneous tissue, is a rare pathological condition in the gastrointestinal tract that is usually diagnosed postoperatively. In this case report, an angiolipoma was diagnosed preoperatively by imaging （including CT scans, abdominal echo, barium enema, and colonoscopy）. This pathology was confirmed postoperatively. Computed tomography scan, abdominal echo, and barium enema images were presented.
