Manometry (Hirschsprung´s Disease)

obst_21a_n.jpg: Anorectal manometry in a 8.10-year-old boy with constipation since early infancy. Y-axis: Course of the intraluminal pressure in mm mercury; basal pressure and spontaneous intestinal activity. X-axis: Course within the registered time. At the bottom: Level of registration in cm from the anus of the registration probe which is pulled out of the anus stepwise. First step: Registration of anorectal pressure profile. The anorectal profile - caused by the levator, internal and external sphincter muscles - is normal; remarkable are only the fluctuating waves of the internal sphincter muscle which are clearly recognizable by their high amplitude. obst_21b_n.jpg: Second step: Stretching of the anal channel with increasing amounts of air from 5 to 20 ml, which is registered by a seperate channel corresponding to the recognizable spontaneous activity of the internal sphincter muscle at the level 5 to 3.5 cm from the anus. During stretching of anal channel there is at no time a pressure drop in the zone of spontaneous internal sphincter activity; in contrast, the fluctuating waves become more regular, and their amplitude higher = missing relaxation reflex of the internal sphincter muscle, or so-called achalasia. In ultrashort congenital megacolon the anorectal manometry is in general superior to biopsy and contrast enema as shown in the presented case; the patient's history revealed a constipation with stool evacuation with an enema only every 10 days. obst_21c_n.jpg: Anorectal manometry in a schoolchild with idiopathic constipation. Sector of the second part of the examination: Stretching of the anal channel with 5 and 10 ml air at the level of the visible spontaneous activity of the internal sphincter muscle 5 cm above the anus. During stretching with 5 ml air there is a minimal, with 10 ml air a distinct relaxation of the internal sphincter muscle. With these findings an aganglionosis or other type of achalasia is improbable, and the constipation is idiopathic. In the first two weeks of life, falsely negative findings are possible in manometry of aganglionosis.