Hemorrhoids are enlargements of the blood vessels located in the anal canal. This canal is supplied with both arterial and venous blood. The arterial system consists of two superior rectal arteries, which participate in the blood supply of the upper part of the anal canal up to the anal valves. These arteries anastomose (branch) with the middle rectal arteries and with the two inferior rectal arteries. In this way, an arterial "plexus" is formed with blood vessels participating in the blood supply of the anal canal as well as of the rectal mucosa. There are also inferior branches of the superior rectal artery.
The venous system consists of the superior rectal vein that drains blood into the portal venous system (through the inferior mesenteric veins), as well as the middle and inferior rectal veins, which drain blood into the venous circulation through the pudendal veins.
There is also a well-expressed network of capillaries and many arterio-venous anastomoses.
This is also the reason why anal bleeding is of a deep red color, because it comes precisely from the rupture of the arterio-venous capillary network.
Thus, blood vessels are a normal component of the anal canal, to which an important role is given in the function of defecation. Many blood vessels as well as adipose and elastic muscular tissue, are capable of spontaneously changing and taking shape by creating the anal ring. In a resting state, the pressure of the anal sphincter is such that it allows the fecal contents not to leak, thanks to the involuntary contractions (contractions) of this muscular ring. Blood vessels contribute to 15% of the sphincter pressure in a resting state.
The dentate line is composed of a swollen line, which separates the mucosal part from the skin of the anal canal. The area above this line is insensitive, while the skin below this line is sensitive to touch.
Hemorrhoids are a common disease that, sometimes, are treated incorrectly. Patients often refuse to undergo a rectal examination for various reasons: fearing the announcement of a possible surgical operation or the discovery of some tumor disease. This examination is very important for the doctor to assess, examine, and think correctly about the way of treating the patient with hemorrhoids. According to a recent study published on this problem in western countries, the percentage of patients suffering from hemorrhoidal disease reaches up to 30%. In fact, it should be emphasized that the real incidence of this problem is probably underestimated due to the silence of individuals not presenting for medical treatment to the doctor.
According to this classification, hemorrhoids are distinguished into two categories.
If we imagine the anus like a clock, the most common areas of hemorrhoids correspond to 3, 7, and 11 o'clock.
Hemorrhoids appear due to the weakening and degeneration of the connective tissue and vascular cushions. Risk factors that accompany this disorder include advanced age, continuous participation of the abdominal muscles during the act of defecation, constipation, and straining of the vascular cushions. The longer the constipation and forced defecation last, the more the risk increases that prolapse and hemorrhoids can occur. Continuous straining during defecation can cause difficulty in the return of venous blood and as a consequence, hemorrhoidal thromboses appear, conditions that can aggravate prolapse and cause bleeding.
This classification divides hemorrhoids into four categories as follows: