Clinical Research Of Dual-energy CT Diagnosis In Intestinal Inflammatory Disease,Colorectal Cancer And Regional Lymph Nodes

Part ⅠIodine map and Spectrum curve in the diagnosis of the inflammatory bowel disease lymph nodes and metastatic lymph nodes in colorectal cancer Backround:The purpose of this study was to explore the diagnostic value of dual-energy computed tomography(DECT)in detecting inflammatory bowel disease LN and metastatic LN in patients with colorectal cancer.Data and Methods:Data from 86 LNs from 30 patients with inflammatory bowel disease(15 patients with ulcerative colitis,5 patients with Crohn’s disease)and 20 patients with colorectal cancer were retrospectively analyzed.All patients received DECT before surgery without any therapy.The iodine contents of the inflammatory bowel disease and colorectal cancer regional lymph nodes were measured using "Liver VNC" software and dual-energy CT based spectral curve was also obtained for each case using MonoEnergetic software.The spectral curve and spectral curve slope were analyzed in "Mono Energetic" mode.Iodine concentration(IC)and the slope of spectrum curve in the both arterial and portal venous phase were being assessed for its diagnostic value.Results:In the pathological findings,51(59.3%)LNs from 30 patients were diagnosed with inflammatory bowel disease and 35(40.7%)LNs from 20 patients were diagnosed with colorectal cancer.The spectrum curve slope of metastatic LNs in the arterial phase(AP)and portal venous phase(PP)was significantly lower compared with LNs(t=28.02,P<0.05;t=25.316,P<0.05).The spectrum curve of both type LNs presents "drop type" with different slope.The mean IC of metastatic LNs in AP was 1.73±0.72mg/ml,which was significantly lower compared with both ulcerative colitis(UC)and Crohn’s disease(CD)LNs(3.39±0.74 mg/ml,2.43±0.40 mg/ml,P<0.001).The mean IC of metastatic LNs in PP was 2.08±0.96mg/ml,which was also significantly lower compared with both ulcerative colitis(UC)and crohn’s disease(CD)LNs(3.81±0.56 mg/ml,2.64±0.53mg/ml,P<0.001).The slope spectrum curve of inflammatory bowel disease LNs and colorectal cancer metastatic LNs in AP were 3.21 ±0.45、2.56±0.47、0.77±0.11,respectively.The slope spectrum curve of inflammatory bowel disease LNs and colorectal cancer metastatic LNs in PP were 33.26±0.49、2.81±0.39、0.63±0.08.Both the mean IC and spectrum curve slope of metastatic LNs in colorectal cancer in AP and PP was significantly lower for inflammatory LNs(P<0.05)Conclusions:DECT-derived iodine content and the slope of spectrum curve differ significantly among inflammatory and metastatic LNs.Part ⅡComparison of Iodine concentration and Overlay values for imaging diagnostic value of the inflammatory bowel disease and intestinal tuberculosisObjective:To explore the value of Iodine content and Overlay value in dual-energy CT in differential diagnosis of the inflammatory bowel disease and intestinal tuberculosis.Data and Methods:54 patients with pathologically confirmed with inflammatory bowel disease and intestinal tuberculosis(ITB)who who underwent contrast enhanced DECT were retrospectively identified.The iodine content and Overlay value of inflammatory and intestinal tuberculosis primary lesions were measured.A receiver operating characteristic(ROC)curve was used to determine the sensitivity and specificity of iodine content and overlay for diagnosis of the inflammatory bowel disease and intestinal tuberculosis.Results:In 54 patients,there are 21 patients with ulcerative colitis(UC)and 24 patients with crohn’s disease(CD).CT value of UC,DC and ITB in the arterial phase were 86.07±12.97HU,89.44±15.65 HU and 82.23±9.53 HU,respectively.CT value of UC,DC and ITB in the portal venous phase phase were 71.71±12.62HU,69.88±14.07HU and 79.00±7.94HU,respectively.Iodine content(mg/ml)was significantly lower for ITB(1.53±0.54)than for UC(2.61±0.42)and DC(2.55±0.50)primary lesions,P<0.0001.Overlay values(HU)was also significantly lower for ITB(25.08±13.85)than UC(51.63±9.33)and DC(41.10±10.95),P<0.0001.The areas under the ROC curve for iodine content and overlay values were 0.898 and 0.822.Conclusion:DECT-derived iodine content and overlay differ significantly among the inflammatory bowel disease and intestinal tuberculosis.Iodine content is superior to overlay value for differential diagnosis of the inflammatory bowel disease and intestinal tuberculosis.Part ⅢComparison study of dual-energy CT spectral curve and Iodine concentration in the inflammatory bowel disease,intestinal tuberculosis and regional lymph nodes Objective:To evaluate the the diagnostic accuracy and the relevance of dual-energy CT(DECT)for the inflammatory bowel disease,intestinal tuberculosis and regional lymph nodes using iodine content and spectrum curve.Data and Methods:This retrospective study included 54 patients with pathologically confirmed with inflammatory bowel disease(IBD)and intestinal tuberculosis(ITB)who underwent contrast enhanced DECT.The iodine content(IC)and the spectrum curve slope of IBD and ITB primary lesions and regional lymph nodes were measured.Results:In the pathological findings,51 LNs from 45 patients were diagnosed with IBD and 16 LNs from 8 patients were diagnosed with ITB.The mean IC and spectrum curve slope of ulcerative colitis(UC)primary lesions in the arterial phase was 2.61 ±0.42mg/ml and 2.12±0.29,which was lower compared with regional inflammatory LNs(3.39±0.73 mg/ml,3.21±0.45,p<0.001).The spectrum curve slope of crohn’s disease(CD)primary lesions in the arterial phase was 1.48±0.47,which was significantly lower compared with regional inflammatory LNs(3.21±0.45,p<0.001).In ITB patients,primary lesions and regional inflammatory LNs between both IC and the spectrum curve slope differences were not statistically significant(t=1.063,p =0.296;t =1.720,=0.096,p>0.05).Conclusion:DECT-derived iodine content and the slope of spectrum curve differ significantly among the IBD primary lesions and regional inflammatory LNs.IBD primary lesions is irrelevant to regional LNs.ITB primary lesions shows sequence homology to regional LNs.The mean IC and spectrum curve slope of IBD in the arterial phase was lower significantly lower than ITB.