Diseases of the rectum and anus / by Charles B. Kelsey.

  • Kelsey, Charles B. (Charles Boyd), 1850-1917.
Date:
1883
Catalogue details

Licence: Public Domain Mark

Credit: Diseases of the rectum and anus / by Charles B. Kelsey. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    These little sacs are arranged in a circular form around the extremity of the rectum. If carefully dissected, they may be seen to be connected with the little veins before mentioned, and also with another little vein which perforates the internal sphincter near its lower edge, and empties into one of the rudimentary branches of the external hsemorrhoidal plexus. Many of these little communicating branches between the external and internal haemorrhoidal systems pass through the substance of the exter- nal sphincter. It results from this, that when the external sphincter is contracted, the anastomosis between the two systems is prevented. Verneuil has laid stress upon the fact that where the internal or su- perior haemorrhoidal veins perforate the rectal wall from within out- wards, they pass through muscular button-holes surrounded by no fibrous tissue and having, therefore, the power of contracting round the vein, closing its calibre, and preventing the return of blood to the liver. In this anatomical arrangement he believes he has found the active cause of internal haemorrhoids. The disposition of the rectal veins into two distinct systems, the one internal and the other external, is fully in conformity with our knowledge of the development of the rectum and anus. The rectal cul-de-sac is at first situated at some distance from the perineum, and as it descends it carries with it its own proper vascular supply. The anal depression is of necessity provided with an independent set of veins, and when the rec- tum and anus are finally united into one canal the two venous systems unite. The internal haemorrhoidal veins also communicate freely with other branches of the internal iliac around the trigone of the bladder by means of minute branches from one-half to one mm. in diameter which pass through the prostate and vesiculae seminales. 2iferves.—The nerves of the rectum and anus are derived from both the cerebro-spinal and sympathetic systems. The former are branches from the sacral plexus, the latter from the mesenteric and hypogastric plexuses. The spinal nerves are derived from the third and fourth sacral which supply visceral branches to all the pelvic organs, anastomos- ing with branches from the sympathetic. The muscular branches from the same nerves have already been spoken of in connection with the in- dividual muscles. The fifth sacral nerve also sends a small twig to the coccygeus. The posterior branch of the superficial perineal nerve from the internal pudic, supplies the skin in front of the anus; while the an- terior branch gives several small filaments to the levator ani. The inferior haemorrhoidal branch from the pudic supplies the lower end of the rectum, the external sphincter, and the skin of the anus. This nerve may come direct from the sacral plexus through the lesser sacro-sciatic notch. The posterior branches of the sacral nerves also sup- ply the skin over the coccyx and around the anus.