The Application Study Of Multi-Slice Spiral CT Thin-Layer And Multiplanar Reformation Technique In Intestinal Obstruction

ObjectiveTo evaluate the clinical value of multi-slice spiral CT (MSCT) thin-layer and multiplanar reformation technique(MPR)in the cause,location and extent of intestinal obstruction.Materials and methods189 patients were suspected of intestinal obstruction were scanned with GE 16-MSCT or GE 64-MSCT,followed with multiplanar reformation technique(MPR).Contrast medium (370mg/ml,80ml Iopamiro) was injected into veins at the speed of 3.5ml/s in order to gain dynamic contrast-enhanced image.Datas were transferred to workstation to reconstruct,including multi-planar reconstruction (MPR),Curved Planar Reformations (CPR),and volume rending (VR).The cause,location and extend of intestinal obstruction were diagnosed, MSCT findings were compared with pathology of surgery or colonoscopy to evaluate the MSCT and MPR of diagnosis value,including the specificity, positive predictive value,negative predictive value,accuracy,Youden index, positive likelihood ratio and negative likelihood ratio of intestinal obstruction. Two independent readers blinded to diagnose only with the transverse images firstly,and then with transverse and MPR images to assure the presence of intestinal obstruction. and abnormal wall enhancement.Concordance of diagnosis,the score of confidence and accuracy of the two diagnostic methods mentioned above were compared.Results1.The diagnostic agreement rate get from transverse CT images and transverse plus MPR images are 91.2% and 95.2% , respectively (not significant).but diagnosis with transverse plus MPR images can improve consistency of two independent readers.(K values were 0.71 and 0.82 respectively),also can improve the confidence score (significant difference,P﹤0.05).2.MSCT and MPR techniques in the diagnosis of intestinal obstruction sensitivity,specificity,positive predictive value,negative predictive value and accuracy,Youden index are 94.8%,96.3%,98.4%,88.1%,95.2%,and 91.1%, respectively;positive likelihood ratio and negative likelihood ratio are 25.6 and 0.04.3.The agreement rate of etiological diagnosis with MSCT and MPR in intestinal obstruction is 90.7%.In detailly the agreement rate of Intrinsic lesions ,intraluminal Lesions,extrinsic lesions are 92.0%,94.7% and 87.2%, respectively (significant difference,χ2=8.79,P<0.05).4.The agreement rate of location of intestinal obstruction with MSCT and MPR are 82.4%.In detailly the agreement rate of intestinal obstruction of duodenum,jejunum,ileum,cecal-ascending colon,transverse colon,descending colon,sigmoid colon,rectum are 100%,76.2%,68.6%,90.9%,85.7%,100%, 91.7%,respectively.If the cases were divided into three groups:duodenum group,jejunum and ileum and colon group,the agreement rate of the three groups are 100%,71.4%and93.3%.there is a significant difference in three groups(χ2=9.92,P=0.007﹤0.05).5.The agreement rate of incomplete intestinal obstruction and complete intestinal obstruction with MSCT and MPR are 89.5% and 100%.There is a significant difference(χ2=8.79,P<0.05).The agreement rate of etiological diagnosis in incomplete intestinal obstruction cases and complete intestinal obstruction cases are 65.8% and 92.0% There is a significant difference (χ2 =13.2,P<0.05).6.The agreement rate of simple intestinal obstruction and strangulated intestinal obstruction with MSCT and MPR are 89.5% and 100%(no significant difference,χ2=3.4592,P=0.0629﹥0.05).Conclusion1.There were no significant difference in the agreement rate of etiological diagnosis with transverse CT images alone, and transverse plus MPR images in the diagnosis of intestinal obstruction,but the latter can improves consistency of two independent readers in diagnosis of intestinal obstruction ,also can improve the diagnosis confidence score. MPR technology is an important supplement in the diagnosis of intestinal obstruction.2.It has high diagnosis value with MSCT and MPR techniques in etiological factor,location and degree of intestinal obstruction,It can be used as the first choice for patients with intestinal obstruction examination.3.The agreement rate of diagnosis with MSCT and MPR techniques in duodenum obstruction and large bowel obstruction are high. but the agreement rate of diagnosis of jejunum- ileum obstruction are slightly low.4.The agreement rate of diagnosis with MSCT and MPR techniques in incomplete intestinal obstruction are slightly low,The agreement rate of etiological factor and location in incomplete intestinal obstruction are also slightly low .