%0 Journal Article
%T Evaluation of anorectal function using real-time tissue elastography before and after preoperative chemoradiotherapy.
%A Sakamoto A
%A Sasaki K
%A Nozawa H
%A Murono K
%A Emoto S
%A Yokoyama Y
%A Matsuzaki H
%A Nagai Y
%A Abe S
%A Shinagawa T
%A Sonoda H
%A Ishihara S
%J Int J Colorectal Dis
%V 39
%N 1
%D 2024 Apr 25
%M 38662090
%F 2.796
%R 10.1007/s00384-024-04633-8
%X <B>OBJECTIVE: </B>This study aimed to clarify the relationship between changes in elasticity and anorectal function before and after chemoradiotherapy.<BR><B>METHODS: </B>This is a single-center prospective cohort study (Department of Surgical Oncology, The University of Tokyo). We established a technique to quantify internal anal sphincter hardness as elasticity using transanal ultrasonography with real-time tissue elastography. Twenty-seven patients with post-chemoradiotherapy rectal cancer during 2019-2022 were included. Real-time tissue elastography with transanal ultrasonography was performed before and after chemoradiotherapy to measure internal anal sphincter hardness as "elasticity" (hardest (0) to softest (255); decreased elasticity indicated sclerotic changes). The relationship between the increase or decrease in elasticity pre- and post-chemoradiotherapy and the maximum resting pressure, maximum squeeze pressure, and Wexner score were the outcome measures.<BR><B>RESULTS: </B>A decrease in elasticity was observed in 16/27 (59.3%) patients after chemoradiotherapy. Patients with and without elasticity decrease after chemoradiotherapy comprised the internal anal sphincter sclerosis and non-sclerosis groups, respectively. The maximum resting pressure post-chemoradiotherapy was significantly high in the internal anal sphincter sclerosis group (63.0 mmHg vs. 47.0 mmHg), and a majority had a worsening Wexner score (60.0% vs. 18.2%) compared with that of the non-sclerosis group. Decreasing elasticity (internal anal sphincter sclerosis) correlated with a higher maximum resting pressure (r = 0.36); no correlation was observed between the degree of elasticity change and maximum squeeze pressure.<BR><B>CONCLUSIONS: </B>Internal anal sphincter sclerosis due to chemoradiotherapy may correlate to anorectal dysfunction.