Ednosonographic Evaluation Of Internal Anal Sphincter In Children Underwent Surgery For Hirschsprung's Disease

ObjectiveThis study aimed to follow up the defecation situation of the children who had underwent operative treatment for Hirschsprung's disease, and to measure the thickness of their internal anal sphincter (IAS) by a ultrasonic machine with an endoanal transducer, combining with anorectal manometry technology, and accordingly to evaluate the analrectal strcture and fuction and the defecation pattern of these children. By studing this , a relationship between postoperative bowel dysfunction and thickness of IAS of the children with Hirschsprung's disease was expected to be confirmed, thereby this would comtribute to a clinical guidance about how exactly thick the IAS should be reserved during the redical operation for Hirschsprung's disease.MethodsThe object of this study was the 40 children who had underwent radical operation for Hirschsprung's disease between 1995-2005 at our hospital. Divide them into the normal defecation function group, the soiling group, the incontinence group and the constipation group, assessing by the criteria of LIZHENG and Rintala respectively. Make all children undergo endoanal ultrasonography and anorectal manometry, and record the indices of thickness of IAS, result of anorectal inhibitory reflex, anal canal resting pressure (ARP) and maximum anal canal pressure (MSP). The difference among groups on thickness of IAS displayed, and a corelation analysis was made among IAS, ARP, MSP, and the score of LIZHENG criteria and Rintala criteria.ResultsIAS of children after operation for Hirschsprung's disease was significantly thinner than that of normal children (5cm: 2.14±0.15 mm vs 1.68±0.45 mm p<0.01); IAS of children in the normal defecation function group was thicker than that in the soiling group and that in the incontinence group (5cm: 1.87±0.50 mm vs 1.69±0.32 mm p<0.05; 1.87±0.50 mm vs 1.42±0.30 mm p<0.05) . IAS of children in the soiling group was thicker than that in the incontinence group (5cm: 1.69±0.32 mm vsl.42±0.30 mm p<0.05); The thickness of IAS of children after operation for Hirschsprung's disease had a corelation with ARP(r=0.641, p=0.033), and had no corelation with MSP. There was no corelation among ARP, MSP, and the score of LIZHENG criteria and Rintala criteria.ConclusionsThe thickness of internal anal sphincter of the children who had underwent operative treatment for Hirschsprung's disease is thinner than normal children, and the thinner the thickness of internal anal sphincter, there will be more severe incontinence. Endoanal ultrasonography play a major role in evaluation of thickness of internal anal sphincter.