J.Jpn. Surg. Soc.. 59(4): 532-568, 1958
CLINICAL AND PATHO-HISTOLOGICAL STUDY OF MEGACOLON CONGENITUM
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Department of Surgery, Branch Hospital, Faculty of Medicine, University of Tokyo. (Director: Dr. Takeo HAYASHIDA) Shigeru TSUZAKI |
Resected specimen was divided into four parts according to macroscopic appearance namely, narrowed, transitional, distal dilated and proximal dilated segment. Roentgenologically, a strongly contructed part was demonstrated at the transitional segment that is situated proximal to the narrowed segment. This contruction was ascertained by balloon method with the findings of characteristic mass contruction wave and intraluminal high teusion at the transitional part and the proximal side of the narrow part. Roentgenologic "contructure figure" and intraluminal high tension by balloon method is seemed to be related to the scantiness of the ganglion cells. "Spasms" is considered to be present here.
Microscopic findings of the plexus myentericus are classified as followings ;
Type I : Nerve cells alone scatter in muscle layers
Type II : Composed of "Nebenzellen" and nerve fiber, not including nerve cells.
Type lll : Same as Type ll, larger in size.
Type IV : Composed of two or three of nerve cells and accompanying "Nebenzellen".
Type V : Nearly normal with less nerve cells and shows degeneration.
Type VI : Normal plexus.
The narrowed segment lacks plexus myentericus and p1. submucosus. And they are replaced by non-myelinated fibers. Muscle and mucosal layers are atrophic and macroscopic narrowing is distinctive (aganglionic segment).
The transitional segment is a portion between the narrowed and the dilated segment, and has 3 to 5 cm. in length. The plexuses are very few (oligoganglionic segment).
Distal dilated segment shows degeneration though it contains a considerable number of plexuses. This is more clearly demonstrated by silver staining. Macroscopically, it extends 6 to 9 cm. from the transitional segment and includes the part of the thickest muscle layer.
Proximal dilated segment is a portion proximal to the distal dilated segment and appears almost normal except that the abnormal neurofibrillae are found.
In the section parallel to the mucosal surface stained by Feyrter's silver method the changes of the network of plexuses are demonstrated more clearly. Hypertrophy and proliferation (Fortsatzdyshermonie by Stöhr) of fine neurofiblillae appear gradually, then atrophy and destruction become more apparent from the oral to the anal portion. It is that the step-like changes are clearly seen such as shrinkage, dissociation, dispersion, ghost image formation and finally disappearance of plexus. These microscopic findi ngs seemed to assure that "Megacolon congenitum" is caused by the disturbance of intramural autonomic nervous system in the lower colon.
Mechanism of the di turbance of defecation in this disease was considered not only by the functional obstruction in the part of absent peristalis but also by the "Spasm" in the oligoganglionic part, the increased resistence of the aganglionic part and by the decreased sense of defecation.
Most reasonable and radical treatment is believed to be surgical operation by Swenson's procedure. Resection must include at least 9- 15 cm. proximal to the narrow part and distal to anal margin. Operation is preferred to be performed at the age of 2-6 years. Other symptomatic megacolon is not indication to this procedure.
In the group of 16 operated patients, one was dead, two have not yet regular voluntary defecation. Other 13 patients gained voluntary defecation in 3 to 6 months.
Some of the important literature are reviewed and mechanism of disappearance of ganglion cells are discussed. Regarding that this disease is often accompanied with other congenital abnormalities and that the morphological changes in diseased colon are peculiar, it might be said that "Megacolon congenitum" is much more "genetisch" in origin.
(author's abstract)
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