关键词: 磁共振, 排粪造影, 老年便秘, 肛提肌板, 肛直角

Abstract: MRI combined with defecography on senile constipation caused by changes of levator plate and anal right Angle        GAO Rong-qing*, SHI Hai-rong, WANG Zhi-min, et al. *The Second Affiliated Hospital Zhejiang University School of Medicine, Hangzhou 310003, China
Corresponding author: WANG Zhi-min, E-mail: jnwzm@126.com
Abstract    Objective    To analyze the imaging mechanism of senile constipation caused by the changes of levator ani muscle plate and anus right angle by MRI combined with defecography. Methods    30 elderly constipation patients admitted to The First Affiliated Hospital Of Shandong First Medical University from September 2019 to September 2022 were selected as the observation group, and 30 elderly healthy volunteers were recruited as the control group at the same time. In both groups, pelvic floor MRI and defecography were performed at rest and during forced ovulation to measure the decline of levator ani muscle plate (△M-Line) and the change of anal right angle (△ARA).  Results    (1) The length of M-Line and the angle of right angle of anus (ARA) in the observation group and the control group at rest were ［(9.79±1.78)mm  vs.(9.65±1.29) mm, P=0.741］ and ［(92.76±3.34)°vs.(93.91±5.48)°, P=0.335］, respectively. There was no significant difference between the two groups (P＞0.05); the M-Line and ARA°of the observation group and the control group were ［(14.81±1.74)mm  vs.(13.79±1.42) mm, P=0.016］ and ［(103.07±4.84)°vs.(106.12±4.89)°, P=0.019］ respectively under the force displacement state, with significant difference (P＜0.05); △M-Line and△ARA°were ［(5.02±1.76)mm  vs.(4.14±1.26) mm, P=0.029］ and ［(10.31±3.36)°vs.(12.21±2.91)°, P=0.021］. There was significant difference between the two groups (P＞0.05); (2) There was a positive correlation between the decline of levator ani muscle plate and Wexner's constipation quantitative score in the observation group under two conditions (correlation coefficient r=0.852, P＜0.05); there was a negative correlation between the change of anal right angle (△ARA°) and Wexner's constipation quantitative score (correlation coefficient r=-0.813, P＜0.05). Conclusion    MRI combined with defectography can dynamically and static observe the decline of levator ANI muscle plate and the change of anal Angle in patients with senile constipation, so as to provide a new basis for clinical accurate diagnosis and treatment of senile constipation.

Key words: magnetic resonance, defecography, senile constipation, levator ani muscle plate, anal right angle