What are Hemorrhoids?
There is no accurate definition of ‘hemorrhoid’. They are a group of veins in the anus, just below the membrane that is located at the bottom part of the anus and rectum. It contains blood vessels and made up of elastic fibers and muscles. The anus is the opening of the rectum to the outside body. The last four centimeters from where the stool passes coming from the rectum to the outside body is the anal canal.
Hemorrhoids are present in everyone contrary to the common belief that it is an abnormality or a disease. It can only be considered abnormal when the hemorrhoidal clumps increase in size or swell.
Prevalence of hemorrhoids
Only 4% of the world population suffers from hemorrhoid problems. Age group of 45 and 65 years of age both men and women are the common target of this problem.
Anatomy of Hemorrhoids
Hemorrhoidal blood vessels get a good supply of arterial blood. The arteries that fill blood to the anal canal come from the rectum. They form a network of blood vessels which surrounds the anal canal. That is why bleeding from hemorrhoids is dark red in color because of the network of arteries that supplies the hemorrhoidal blood vessels.
The anal veins remove blood from the hemorrhoids and the anal canal. They drain blood in two different directions, the first one is directing upwards towards the rectum and the second one is downwards below the skin around the anus. There is a line within the anal canal which represents the transition from anal skin to the lining of the rectum that line is called the dentate line.
Formation of hemorrhoids
Internal hemorrhoid is determined when the hemorrhoid comes from the top of the anal canal also known as the rectal side. If it is located at the bottom part of the anal canal besides the anus, it is called an external hemorrhoid. In general the type of hemorrhoid is determined by locating its position that is if it is below or above the line within anal canal which is also called the dentate line.
As mentioned above, hemorrhoidal tissues at the top of the anal canal, inside the rectum, are formed from the blood vessels and tissues supporting them. There are primarily three major hemorrhoidal cushions oriented right posterior, right anterior and left lateral. Vessels of the anal cushions are irritated and the supporting tissues swell when the formation of enlarged internal hemorrhoid takes place. This causes problems when the blood vessels and mass of tissues prolapse into the anal canal. It is still unclear how external hemorrhoids are formed.