To establish the grade of rectocele (RC) in echodefecography (EDF) on the basis of the previous establishment of EDF, with a standard of RC grading in X-ray defecography (X-ray). And analyze the correlation between the grading and the clinical symptoms of outlet obstruction constipation(OOC).

Forty-nine female patients diagnosed with RC were studied, collected from December 2018 to April 2021 in the Anorectal Treatment Center of The Second Affiliated Hospital of Nanjing University of Chinese Medicine. Among these, thirty-seven patients were diagnosed with OOC and 12 with functional anorectal pain (FAP). Both X-ray and EDF were performed in 38 patients. First, the values of the two examinations of 38 patients with RC were analyzed by linear regression, and the RC grading of EDF was calculated. On this basis, Logistic regression analysis was conducted on the RC grading of 37 OOC patients and their constipation symptoms.

The regression equation was obtained by linear regression analysis: y=0.188x+5.97 3 (regression coefficient; P=0.014; constant: P=0.001). According to X-ray criteria, the mild one in EDF was 7 mm~9 mm,the moderate one was 9 mm~12 mm and the severe one was over 12 mm. Logistic regression analysis results: there was no significant correlation between RC grading and patients' self-defecation (P=0.738), anal pendant expansion (P=0.894), abdominal (distension) pain (P=0.721) and mild symptoms of defecation difficulty (P=0.648), sense of defecation obstruction (P=0.686), sense of defecation failure (P=0.729), decrease of defecation frequency (P=0.108). But there was a strong correlation with moderate and severe symptoms such as defecation difficulty (P=0.021; P=0.036), sense of defecation obstruction (P=0.038; P=0.015), sense of defecation failure (P=0.032; P=0.026), decrease of defecation frequency (P=0.008), of which the correlation with moderate and severe defecation difficulty was the largest (P＜0.05).

The RC grading in EDF was associated with clinical symptoms of OOC,such as defecation difficulty, sense of defecation obstruction, sense of defecation failure, decrease of defecation frequency, and especially closely related to defecation difficulty. It suggests that EDF is an effective method to diagnose RC. The sample size of this study was small, so the next step is to expand the sample size for further exploration and multi-center study to further determine its value.