Aim: The term ultra short is not clearly defined in ultrashort-segment Hirschsprung's disease. The limited extent of the 
ultrashort-segment Hirschsprung's disease allows for the treatment with extended sphincteromyectomy. This procedure 
could be diagnostic and therapeutic one. The study was designed to evaluate the role of posterior myectomy in children 
with refractory constipation in the diagnosis and treatment of ultrashort-segment Hirschsprung's disease. 
Methods: A descriptive cross sectional study was carried out among 40 pediatric patients (1 – 12 years) with refractory 
constipation without obvious organic causes. Detailed history, examination, barium enema and anorectal manometry 
were performed to all children. Posterior anorectal myectomy was performed to the studied patients. The outcome and 
postoperative complications were assessed for all children. 
Results: Agangliosis was diagnosed in 24 patients (60%) among whom constipation was improved in 75% while it was 
improved among (50%) of the ganglionic group. Abdominal distension, soiling and anorectal manometric studies were 
markedly improved after surgery in both aganglionic and ganglionic groups. Rare postoperative complications were 
reported among only five patients (12.5%). 
Conclusion: Anorectal myectomy is an effective procedure in managing refractory constipation in pediatrics and also for 
the diagnosis of Ultrashort segment Hirschsprung's disease and is curative in such cases.