Hemorroids overview

In the upper anal canal, the hemorrhoids cushions are composed of three submucosal pillars of sinusoids within connective tissue, generally in the left lateral, right anterior, and right posterior. During the act of defecation, the hemorrhoids cushions become engorged with blood, cushioning the anal canal and supporting the anal canal lining. The pathologic term hemorrhoids is used to describe the downward displacement of the cushion along with dilation of the contained sinusoids and sometimes bleeding from the arteriole, venule, or sinusoidal portion.Hence, hemorrhoids develop when the supporting tissues of the anal cushion deteriorate or with extensive downward pressure, as in prolonged straining at stool or pregnancy.

The most common complaints of burning, itching, swelling, and pain usually are not from hemorrhoids but result from pruritus ani, anal abrasion, anal fissure, thrombosed external hemorrhoids, or prolapsed anal papilla. Symptoms are aggravated by constipation and diarrhea. The most common manifestation of hemorrhoids is painless, bright red rectal bleeding associated with bowel movement. With severe hemorrhoids,the patient commonly describes the bleeding episode as blood dripping into the toilet bowl. A feeling of incomplete evacuation is also common. In chronic prolapse, exposed rectal mucosa often causes perianal irritation and mucus staining on the underwear. Congestion of external hemorrhoids or skin tags can cause discomfort. Except in the presence of thrombosis, pain is rarely an early symptom of hemorrhoidal disease and other diagnoses should be excluded.

According to modern concepts, prolapse of anal cushions is initiated by the shearing effect of the passage of a hard stool or by excessive downward pressure as with constipation, pregnancy, or childbirth, or by the precipitous act of defecation as in urgent diarrhea. If prolapse of the vascular cushions can be prevented or if the congesting effect of a tight anal canal can be abolished, the anal cushions return to their normal state and symptoms are ameliorated without necessitating removal of the cushions themselves. Therefore, the rationale of giving bulk in the diet is to eliminate straining at defecation by producing soft, bulky stool. A high-fiber diet usually reduces symptoms of hemorrhoids and is ideal for first- and second-degree hemorrhoids.