The pathogenesis of idiopathic megacolon.

BACKGROUND: Even today, the pathogenesis of idiopathic megacolon is still a subject of controversy. Anomalies of the gastrointestinal autonomous nervous system or of the smooth muscle of the muscularis propria are being considered. METHODS: Sixty-three idiopathic megacolon resections between 1997 and June 2004 were investigated. The native specimens were coiled caudo-cranially and cryostat-cut. Connective tissue was stained with picric acid/Sirius red after Delauney fixation. Immunohistochemistry was performed for collagen types I, II, III and IV, as well as smooth muscle actin, vimentin, desmin fibronectin and CD117 for interstitial cells of Cajal. The enteric nervous system was examined by enzyme histochemistry for acetylcholine-esterase, lactate dehydrogenase, succinic dehydrogenase and nitroxide synthase. RESULTS: Histologically, idiopathic megacolon was characterized by a total atrophy of the collagenous tendinous connective tissue membrane of the myenteric plexus and the tendinous collagen fibre net of the muscularis propria. Immunohistochemically, mainly collagen type III was missing in the muscularis propria. Interestingly, the incidence of idiopathic megacolon in those of the female sex was seven times more frequent than in the male sex. The myenteric plexus was normal in the majority of patients. Interstitial cells of Cajal, collagen II and IV, as well as smooth muscle actin, desmin and fibronectin showed no consistent alteration. CONCLUSION: A normally structured tendinous fibre net of muscularis propria is an essential prerequisite for effective gut peristalsis. Atrophy of the tendinous fibre net abolishes peristalsis and allows for unlimited distension of the colon. A diagnosis of idiopathic megacolon can reliably be made on a collagen stain. The normal findings of myenteric plexus support the hypothesis that a primary metabolic defect of muscularis propria may be the underlying cause of idiopathic megacolon.

Prospective, randomized study: proximate PPH stapler vs. LigaSure for hemorrhoidal surgery.

PURPOSE: It has been shown that for hemorrhoidal surgery both LigaSure and stapler cause less pain than diathermy or scissor dissection. This study has attempted to establish which of the less painful alternatives proves best in an unselected series of patients with hemorrhoidal disease. METHODS: Fifty patients were randomized to undergo stapling hemorrhoidopexy or LigaSure hemorrhoidectomy. Parameters investigated were pain (primary parameter), patient satisfaction with treatment, and recovery of personal activity. Other factors investigated were operative result, ease of handling, analgesic requirements, and postoperative course. RESULTS: Both methods were found to be equivalent in all major aspects analyzed. Postoperative pain scores (P = 0.99), patient satisfaction (P = 1), and self-assessment of activity (P = 0.99) were almost identical in both groups of patients. Significant differences were found in none of the numerous factors investigated. CONCLUSION: Both methods can be used safely and without major disadvantage for the patient regardless of stage and extent of hemorrhoidal disease.