Objective:To investigate the role of coupler perfusion in transrectal ultrasound in the diagnosis of preoperative T staging of rectal cancer.Methods:A retrospective analysis of the preoperative clinical data of 132 patients with rectal cancer in the People′s Hospital of Inner Mongolia Autonomous Region from June 2015 to November 2020. According to whether or not the patients agreed to coupler perfusion before ultrasound examination, they were divided into 2 groups, namely the perfusion group 69 cases and the non-perfusion group of 63 cases, with postoperative pathology as the gold standard, and compared with magnetic resonance imaging(MRI) to evaluate the accuracy of the 2 groups and MRI in the T staging of rectal cancer.Results:The total coincidence rates of the coupling agent perfusion group, non-perfusion group and MRI group for the diagnosis of rectal cancer T staging were 89.9%, 76.2% and 87.9%, respectively, and the difference among the three methods was statistically significant (χ 2=6.096, P=0.047). The diagnostic sensitivity of the coupling agent perfusion group for T1 stage was 96.0%, which was higher than 61.5% of the non-perfusion group and 92.3% of the MRI ( P=0.010). The specificity of the perfusion group for the diagnosis of T2 stage was 95.7%, higher than the non-perfusion group and MRI ( P=0.037), the positive predictive value of the perfusion group for T2 stage was 90.9%, which was higher than the non-perfusion group and MRI ( P=0.035). The diagnostic accuracy of the perfusion group for T2 stage was 94.2%, higher than the non-perfusion group and MRI (χ 2=7.070, P=0.029). There were no statistically significant differences in diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy among the perfusion group and the non-perfusion group and the MRI for T3 and T4 (all P>0.05). Conclusions:Coupled-agent perfusion makes it convenient and fast for intracavity ultrasound to diagnose T staging of rectal cancer, and the diagnostic efficiency is comparable to MRI. In particular, it can be used as a highly reliable imaging method for T1 and T2 rectal cancer.

Objective:To evaluate the value of transrectal ultrasound(TRUS)in diagnosing extramural venous invasion(EMVI) of rectal cancer.Methods:Clinical data of 81 rectal cancer patients were retrospectively analyzed in the People′s Hospital of Inner Mongolia Autonomous Region from January 2015 to December 2021. The extramural vascular sonographic features in these patients were summarized. Based on the postoperative pathology and compared with MRI examination, the efficacy of TRUS for the diagnosis of EMVI in rectal cancer was investigated.Results:①According to the sonographic presentation, extramural vessels of rectal cancer can be divided into the following four types: typeⅠshowed that the mass broke through the muscularis propria of the intestinal wall, and no peripheral vascular shadow was observed; typeⅡshowed that the mass broke through the muscularis propria, surrounded by extraneous vessels with normal diameter, running and blood flow; type Ⅲ showed that the mass broke through the intrinsic muscle layer of the intestinal wall and was surrounded by extramural vessels with abnormally thickened diameters, and blood flow filling defects; type Ⅳ showed a mass that broke through the intrinsic muscular layer, with irregularly dilated vessels outside the peritumoral wall and no blood flow signal in the lumen. ②With type Ⅲ and type Ⅳ as positive signs of EMVI, the diagnosis compliance rate of TRUS was 90.1% (Kappa=0.580, P<0.001), sensitivity was 58.3%, specificity was 95.7%, positive predictive value was 70.0%, negative predictive value was 93.0%, and area under the ROC curve(AUC) was 0.770. The diagnosis compliance rate of MRI was 86.4% (Kappa=0.541, P<0.001), sensitivity was 75.0%, specificity was 88.4%, positive predictive value was 52.9%, negative predictive value was 95.3%, and the AUC was 0.817. The differences in sensitivity and specificity between TRUS and MRI for the diagnosis of rectal cancer EMVI were not statistically significant ( P>0.05), and the differences in the AUC were not statistically significant ( Z=0.447, P=0.655). Conclusions:TRUS is valuable in assessing the extramural vascular status of rectal cancer and is expected to be an effective imaging method for preoperative diagnosis of EMVI.