Morphometric assessment of Hirschsprung's disease: associated hypoganglionosis of the colonic myenteric plexus.

At present, there are no generally acceptable criteria for the evaluation of hypoganglionosis of the myenteric plexus. The aim of this morphometrical investigation was to examine the most important quantitative characteristics of hypoganglionosis. Colon specimens from 35 children with Hirschsprung's disease were assessed morphometrically. Twenty specimens with Hirschsprung's disease and proximal hypoganglionosis of the myenteric plexus were compared with 15 specimens with Hirschsprung's disease and normal innervation in the proximal myenteric plexus. All native surgical specimens were caudocranial coiled and sectioned in a cryostat. Nerve cells and ganglia were selectively stained with an enzyme-histochemical lactic dehydrogenase reaction. Morphometric measurements were done with an optic-electronic image analysis system. Hirschsprung's disease-associated hypoganglionosis of the myenteric plexus is characterized by a significant decrease in ganglion cross-sectional area (-56.2%) and in plexus area per mm colon (-53.5%). Together with these data, an increase in ganglion distance (+20%) was also determined, and the number of nerve cells per mm colon was decreased by -25.5%. The decrease in ganglion area and in the number of nerve cells per mm colon in the myenteric plexus proved to be the most characteristic parameters of a hypoganglionosis.