The structure of the transitional and aganglionic zones of Auerbach's plexus in patients with Hirschsprung's disease: a computer-assisted three-dimensional reconstruction study.

Intestines resected from two patients with Hirschsprung's disease, both aged 6 months, were submitted to serial sectioning and three-dimensional reconstruction to visualize the overall structure of Auerbach's plexus and correlate its changes with functional abnormalities. Reconstruction was made possible by using a graphics computer system. In normal intestines taken from an autopsy case, both large and small, the plexus was shown extending along the intermuscular septum as a regular network. But in the large intestine, the density of the network was apparently higher and the individual bundles thicker than in the small intestines. This neural network was absent in the aganglionic zone in Hirschsprung's disease, as expected, where only hypertrophic extrinsic nerves were running in the septum. The "transitional zone" of Hirschsprung's disease was clearly definable as an area extending over a certain length, where the network meshes grow more irregular and the bundles taper more, toward the aganglionic zone. This finding was considered to be of profound significance in the design of a surgical strategy to prevent postoperative bowel dysfunction. In determining the range of resection, one must consider not only the presence or absence of nerve cells but also the grade of plexus hypoplasia.