Read N W, Abouzekry L
Gut. 1986 Mar;27(3):283-7. doi: 10.1136/gut.27.3.283.
To elucidate the phenomenon of faecal incontinence in impacted patients, manometric, radiological and other investigations were carried out in 55 elderly patients, who had impacted masses of faeces in the rectum and were incontinent of faeces and 36 elderly control subjects with no anorectal problems. Maximum basal pressure and the maximum squeeze pressure in impacted patients were not significantly different from elderly controls. Sphincter pressures were no different after disimpaction than they were with faecal masses in situ, suggesting that leakage and soiling were not caused by stretching of the anal ring or prolonged reflex inhibition of anal tone by the faecal mass. The anorectal angle was more obtuse in impacted patients than in elderly controls though there was no greater degree of perineal descent. Anal and perianal sensation was impaired in impacted patients compared with controls. Rectal sensation was also impaired in the impacted patients in that the volume in a rectal balloon that could be perceived by the subject and the volume that gave rise to a desire to defecate were much higher in impacted patients than in controls. The rectal volume required to cause anal relaxation was lower in impacted patients compared with controls though there was no reduction in the volume at which anal relaxation failed to recover its resting tone. Rectal distension elicited external sphincter contractions in 53% impacted patients compared with 80% of controls. In conclusion, faecal soiling in patients with faecal impaction is probably related to the combination of an obtuse anorectal angle and the low anal pressures, normally found in the elderly and to impaired anorectal sensation which prevents conscious contraction of the external sphincter when the internal sphincter is relaxed.
为阐明便秘患者大便失禁的现象，对55例直肠内有干结粪块且大便失禁的老年患者以及36例无肛肠问题的老年对照者进行了测压、放射学及其他检查。便秘患者的最大基础压力和最大收缩压力与老年对照者相比无显著差异。解除粪块嵌塞后括约肌压力与粪块存在时相比无差异，这表明渗漏和弄脏并非由肛门环拉伸或粪块对肛门张力的长期反射性抑制所致。便秘患者的肛肠角比老年对照者更钝，尽管会阴下降程度并无更大。与对照者相比，便秘患者的肛门及肛周感觉受损。便秘患者的直肠感觉也受损，表现为患者能感知到的直肠气囊容积以及引起便意的容积在便秘患者中比对照者高得多。与对照者相比，便秘患者引起肛门松弛所需的直肠容积更低，尽管肛门松弛未能恢复静息张力时的容积并无减少。与80%的对照者相比，53%的便秘患者直肠扩张时引发外括约肌收缩。总之，粪块嵌塞患者的大便弄脏可能与肛肠角钝、肛门压力低（这在老年人中常见）以及肛肠感觉受损有关，肛肠感觉受损会导致内括约肌松弛时外括约肌无法有意识地收缩。
