Study Of Clinical Application On Spectral CT Imaging In Intestinal Lesions

Part One: the spectral CT features of normal intestinal wallObjective To explore the spectral CT features of normal intestinal wall.Methods 30 volunteers without intestinal lesions(confirmed by endoscopy) underwent plain and arterial phase enhanced spectral CT scanning. All spectral imaging data were analysed with GSI viewer, measured the iodine(water) concentration of the jejunum, ileum, left colon, right colon, and got the CNR image and the CNR value, respectively in the arterial phase.30 volunteers were divided into three groups according to age(18 years to 30 years for the A group, 30-year-old to 50 years old for the B group, 50 to 65 years for the C group), statistical description of the mean and 95% confidence intervals for statistical analysis. Results A group, Mean CNR value of jejunum :53.47 ± 0.83, interval(51.76,55.17), the mean iodine(water) concentration:11.84 ± 0.22, interval(11.38,12.29);B Group, mean CNR value of jejunum:53.60 ± 0.80,interval( 51.97,55.23),mean iodine(water) concentration:11.50 ± 0.23,interval(9.01,11.97).C group, mean CNR value of jejunum :54.17 ± 0.67,interval(52.79,55.54), the mean iodine(water) concentration: 11.51 ± 0.41, interval(9.03,12.91). mean CNR value of ileum :52.33 ± 0.87, interval(50.55,54.11), iodine(water) mean concentration:11.05 ± 0.37, interval(10.21,13.34), B group, mean CNR value of ileum 51.34 ± 0.78, interval(49.92,53.78), the mean iodine(water) concentration:11.01 ± 0.67, interval(10.08,12.48), C group, mean CNR value of ileum51.34 ± 0.56, interval(49.00,53.01). the mean iodine(water) concentration 11.34 ± 0.56, interval(10.03,12.76).A group, mean CNR value of left colon 55.03 ± 0.63, interval(53.74,56.33), the mean iodine(water) concentration 9.80 ± 0.08, interval(9.64,9.96), B group, mean CNR value of left colon55.43 ± 0.60, interval(54.20,56.66), mean iodine(water) concentration 9.71 ± 0.14, interval(8.42,11.08); C group, mean CNRvalue of left colon 56.07 ± 0.53, interval(54.98,57.15), the mean iodine(water) concentration 9.01 ± 0.13, interval(8.75,10.27). A group, mean CNR value of right colon 55.20 ± 0.62, interval(53.92,56.48), mean iodine(water) concentration 9.17 ± 0.13, interval(8.90,11.44), B group, mean CNR value of the right colon 55.67 ± 0.56, interval(54.53,56.81), the mean iodine(water) concentration 9.12 ± 0.21, interval(8.68,11.55). C group, the mean CNR value of right colon 56.13 ± 0.52, interval(55.07,57.19), the mean iodine(water) concentration 9.01 ± 0.24,interval(8.52, 10.49).Conclusion:normal intestinal wall of spectrum CT imaging has certain characteristics.Part Two: The Application of Spectral CT in the inflammatory bowel diseasePurpose To explore the clinical value of spectral CT imaging in inflammatory bowel disease.Methods A retrospective analysis of spectrum CT data of 20 patients with pathologically confirmed of inflammatory bowel disease, including 10 cases of ileocecal intestinal tuberculosis, 10 cases of ulcerative colitis.And select 10 volunteers without intestinal lesions.All subjects underwent dual-phase spectral CT scan(arterial, venous phase), the lesions were measured on spectrum analysis software,including normal intestinal wall, 40 ~ 140 ke V(interval 10 ke V) CT values, iodine(water)concentration, water(iodine) concentration.Compare the difference between the two groups,compared with pathological results. Statistical analysis was performed using two independent samples t test. Results [1] 40 ~ 90 ke V CT value of normal intestinal wall were lower than the intestinal tuberculosis in the arterial and venous phase, and the difference was statistically significant(P <0.05);concentration of iodine content of intestinal tuberculosis was higher than normal intestinal wall in arterial and venous phase,the difference was statistically significant(P <0.05);[2] 40 ~ 90 ke V CT value of ulcerative colitis were higher than the normal colon wall in arterial and venous phase, and the difference was statistically significant(P <0.05); iodine concentrations of intestinal tuberculosis were significantly larger than normal colon wall in arterial and venous phase,the difference was statistically significant(P <0.05).Conclusion The quantitative parameters of spectrum CT imaging can help identify inflammatory bowel disease with normal intestinal wall.Part Three:The value of spectrum CT in differential diagnosis of the Intestinal LesionsObjective to explore the value of spectrum CT in differential diagnosis of the benign and malignant Intestinal lesions.Methods A retrospective analysis of 41 patients with colorectal cancer and 10 patients with ulcerative colitis, 10 patients with intestinal tuberculosis,all pathologically confirmed. All patients underwent plain and two phases enhanced spectral CT scan.All spectrum imaging data were analysed with GSI viewer to obtain CT value and iodine(water) concentration on different monochromatic images. Results The CT value on 40~80ke V monochromatic images and iodine concentration were higher in colorectal cancer than those in ulcerative colitis and intestinal tuberculosis.in arterial and venous phase,but water concentration was lower than that in ulcerative colitis and intestinal tuberculosis(all P <0.05). The diagnostic sensitivity and specificity for colorectal cancer were 100%, when the thresholds of 50 ke V,was set as 129.71 Hu respectively In arterial phase.60 ke V was set as 120.64 Hu respectively in arterial,iodine concentration was set as 11.96(100μg /㎝3).Also,when the thresholds of 50 ke V was set as 179.08 Hu respectively In arterial phase.60 ke V was set as 128.46 Hu respectively in venous phase. Conclusions spectrum CT have certain value for differential diagnosis of the benign and malignant Intestinal lesions.Part Four:The Studies of Preoperative Staging of Colorectal Cancer with Spectral CTPurpose To explore the clinical value of gemstone spectral imaging(GSI) with spectral CT in evaluating preoperative T stage and N stage of colorectal cancer. Methods A retrospective analysis of CT parameters of 41 cases with advanced colorectal cancer, with pathologically confirmed,of which21 patients had fatty infiltration around the intestine.All patients underwent preoperative CT dual-phase spectra(arterial, venous phase) enhanced scan, and measured and analyzed the Spectrum parameters with spectrum analysis software,including colorectal cancer lesions, normal intestinal wall,fat around the intestine,regional lymph nodes, and the results were compared with the pathological.Results T stage: with the arterial and venous phase CT images,the measurement of colorectal cancer lesions and normal distal intestinal wall、fatty infiltration and normal fat,including 40 ~ 140 ke V CT values,iodine(water) concentration,water(iodine) concentration. Data were analyzed statistically by independent-samples T-test. N staging: Two senior abdominal radiologists analyzed all the cases by double-blind method.Lymph node evaluation with spectrum CT method(shape of lymph node are identical or similar with the lesion spectrum curve,evaluated as metastatic lymph nodes) and conventional CT method(by observing the size of lymph nodes, the length and diameter,the CT values),and compare two methods for accurate assessment of N staging of colorectal cancer;When the diagnosis of two radiologists were different, to discuss in order to determine the final results. Results[1] in arterial and venous phase,the 40 ~ 90 ke V CT value of colorectal cancer lesions were significantly higher than the normal intestinal wall, the difference was statistically significant(P<0.05); in arterial and venous phase,iodine concentration of colorectal cancer were higher than normal intestinal, the difference was statistically significant(P <0.05). [2] in arterial and venous phase,40 ~ 140 ke V CT values of Invaded fat were higher than normal fat, and the difference was statistically significant(P <0.05); in arterial and venous phase,iodine concentration of Invaded fat was significantly higher than normal fat, the difference was statistically significant(P <0.01). [3] The accuracy of spectral CT method to assess N stage ofcolorectal cancer was 73%, which was significantly higher than traditional CT method(61%)(χ2=3.737, P<0.05). the difference was statistically significant. Conclusion quantitative parameters of spectrum CT imaging can help identify colorectal cancer lesions and normal intestinal wall, invaded fat and normal fat, and can more accurately determine the metastatic lymph nodes, Thus provide the basis for pre-surgery CT in colorectal cancer stage, N stage clinical evaluation.