[Functional echo morphology of Bauhin's valve].

Following rectal irrigation, it is possible to demonstrate the ileo-caecal valve sonographically, using a right para-inguinal approach. The shape, position and motility of the valve can be evaluated. The normal valve is two to three mm. thick, similar to the colonic wall, but its lips are thickened. Two distinct mechanisms are responsible for opening the valve, the ileocolic pressure gradient and relaxation of the circular muscle round the valve. The resulting intraluminal flow can be quantified by duplex sonography. The information may be of diagnostic and therapeutic significance, particularly during childhood.