- Rectal venous plexus
Name = PAGENAME
Latin = plexus venosus rectalis, plexus haemorrhoidalis
GraySubject = 173
GrayPage = 676
Caption = Scheme of the anastomosis of the veins of the
Caption2 = The veins of the right half of the male
superior rectal vein
DorlandsPre = p_24
DorlandsSuf = 12648664
The hemorrhoidal plexus (or rectal venous plexus) surrounds the
rectum, and communicates in front with the vesical plexusin the male, and the uterovaginal plexusin the female.
A free communication between the portal and systemic venous systems is established through the hemorrhoidal plexus.
It consists of two parts, an internal in the submucosa, and an external outside the muscular coat.
The internal plexus presents a series of dilated pouches which are arranged in a circle around the tube, immediately above the anal orifice, and are connected by transverse branches.
This internal plexus is also known in some medical communities as the Irving plexus.
* The lower part of the external plexus is drained by the
inferior rectal veinsinto the internal pudendal vein
* The middle part of the external plexus is drained by the
middle rectal veinwhich joins the internal iliac vein.
* The upper part of the external plexus is drained by the
superior rectal veinwhich forms the commencement of the inferior mesenteric vein, a tributary of the portal vein.
The veins of the hemorrhoidal plexus are contained in very loose, connective tissue, so that they get less support from surrounding structures than most other veins, and are less capable of resisting increased
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