ON THE zETIOLOGY

The signs and symptoms of congenital dilatation of the colon are well enough recognized to require no elaboration in this short communication, the purport of which is to describe a pathological basis for the disease and to report the results of the histological examination of two examples. I can find no reference to such histological changes as are recorded here in the relevant literature. Both cases investigated were in boys, aged 10 and 7 years respectively, and were typical in every respect. The second case is described here. Marroscopic Examinttion. The colon is distended from the cectim to the pelvi-rectal sphincter; its width being five times that of the sphincter. The wall above the sphincter is about four times the thickness of the wall at the sphincter, and the enlargement is chiefly confined to the circular muscular coat. Microscopic Examination. (a) Through the distended area. The mucosa, the muscularis mucosoe, and the submucous layers all show some fibrous thickening; the circular muscular fibres are greatly hypertrophied, the longitudinal to a lesser degree. The cells of Auerbach's plexus appear healthy but some fibrous change is apparent in their surroundings. (b) Through the sphincter. No changes of importance are noted in the epithelial layer and glands, the muscularis mucosae, or the submucous layer, although a few inflammatory cells are found throughout. The circular muscle coat is in sharp contrast to the area above and is of normal thickness, as also is the longitudinal layer, and shows little alteration apart from some fibrous and fatty degeneration. In the intermuscular plexus of nerve cells the changes are of a striking character. As the accompanying microphotographs (Figs. 1 and 2) show, the ganglia atre replaced by inflammatory cells. In the ganglion which is shown under the higher magnification, only one nerve cell, shrunken and degenerated, is to be seen.