Objective To investigate the effects of tagged fluid and substraction in CT virtual colonoscopy (CTVC) on the conspicuity of polyps and to confirm the optimal attenuation value and the optimal viewing window. Methods Polyps measured 3-10 mm were created in fresh porcine colon in vitro and submerged in saline and mixed with positive contrast medium for the CT values of 200 HU, 400 Hu, 600 HU, and 800 HU. Polyps were measured before and after substraction and compared with those in the control group. The effects of different viewing windows and different attenuation values on the measurement and conspicuity of polyps were analyzed. Results The optimal attenuation value of tagged fluid was 800 HU and the optimal viewing window was colon (-150 HU, 1 500 HU) and bone (500 HU, 2 500 HU). Conclusion The combination of tagged fluid and CT substraction can improve the conspicuity of small polyps covered by colonic fluid.

Objective To investigate the feasibility and efficacy of endoscopic catheterization of ileus tube combined enterectomy for the treatment of elderly patients with acute sigmoid volvulus. Methods From August 2015 to August 2017,27 cases of elderly patients with acute sigmoid volvulus received treatment of endoscopic placement of ileus tube combined enterectomy in Pudong New Area Gongli Hospital.Retrospectively collected clin-ic parameters of pre-catheterization,post-catheterization,enterectomy and postoperative follow-up;the success rate of catheterization and enterectomy,compression efficiency,post-operative complications,and efficacy of the com-bined therapy were analyzed. Results Emergency catheterizations of anorectal ileus tube were succeeded in 27 (100%)patients;one patient who developed intestinal gangrene received emergency enterectomy,the hemogram and internal environmental disturbance of the 26 cases were significantly relieved,and the efficacy rate of decom-pression was 96.3%. The success rate of was enterectomy was 100%;the incidence of severe complications and mortality were 22.2% and 3.7%,respectively. During the follow-up,2(7.4%)patients developed ileus,and the efficacy rate of the combined therapy was 85.2%. Conclusions The catheterization of ileus tube could effectively depress intestinal pressure. The success rate of enterectomy was significantly improved and postoperative mortality was reduced. The therapy of endoscopic ileus tube catheterization combined enterectomy is a safe and effective method for the treatment of acute sigmoid volvulus in the elderly.