Rectal venous plexus

Rectal venous plexus

Infobox Vein
Name = PAGENAME
Latin = plexus venosus rectalis, plexus haemorrhoidalis
GraySubject = 173
GrayPage = 676


Caption = Scheme of the anastomosis of the veins of the rectum.


Caption2 = The veins of the right half of the male pelvis.
DrainsFrom =
Source =
DrainsTo = superior rectal vein
Artery =
MeshName =
MeshNumber =
DorlandsPre = p_24
DorlandsSuf = 12648664
The hemorrhoidal plexus (or rectal venous plexus) surrounds the rectum, and communicates in front with the vesical plexus in the male, and the uterovaginal plexus in the female.

A free communication between the portal and systemic venous systems is established through the hemorrhoidal plexus.

Parts

It consists of two parts, an internal in the submucosa, and an external outside the muscular coat.

Internal plexus

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.

External plexus

* The lower part of the external plexus is drained by the inferior rectal veins into the internal pudendal vein

* The middle part of the external plexus is drained by the middle rectal vein which joins the internal iliac vein.

* The upper part of the external plexus is drained by the superior rectal vein which forms the commencement of the inferior mesenteric vein, a tributary of the portal vein.

upport

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 blood-pressure.


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • rectal venous plexus — n a plexus of veins that surrounds the rectum and empties esp. into the rectal veins called also rectal plexus …   Medical dictionary

  • rectal vein — n any of three veins that receive blood from the rectal venous plexus: a) one draining the lower part of the rectal venous plexus and emptying into the internal pudendal vein called also inferior hemorrhoidal vein, inferior rectal vein b) one… …   Medical dictionary

  • rectal plexus — n RECTAL VENOUS PLEXUS * * * 1. p. venosus rectalis. 2. see p. rectalis inferior, p. rectalis medius, and p. rectalis superior …   Medical dictionary

  • plexus venosus rectalis — [TA] rectal venous plexus: a venous plexus that surrounds the lower part of the rectum and drains into the rectal veins; called also hemorrhoidal p …   Medical dictionary

  • rectal plexus inferior — 1. the subcutaneous portion of the rectal venous plexus, below the pectinate line. 2. p. rectalis inferior …   Medical dictionary

  • rectal plexus superior — 1. the submucosal portion of the rectal venous plexus, above the pectinate line. 2. p. rectalis superior …   Medical dictionary

  • venous plexus rectal — p. venosus rectalis …   Medical dictionary

  • plexus — A network or interjoining of nerves and blood vessel s or of lymphatic vessels. [L. a braid] abdominal aortic (nervous) p. [TA] an autonomic p. surrounding the abdominal aorta, directly continuous with the thoracic aortic p. superiorly and …   Medical dictionary

  • Vein — A blood vessel that carries blood low in oxygen content from the body back to the heart. The deoxygenated form of hemoglobin (deoxyhemoglobin) in venous blood makes it appear dark. Veins are part of the afferent wing of the circulatory system… …   Medical dictionary

  • zone — A segment; any encircling or beltlike structure, either external or internal, longitudinal or transverse. SEE ALSO: area, band, region, space, spot. SYN: zona (1) [TA]. [L. zona] …   Medical dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”