Hemorrhoids are medical condition caused by a pathological increase in internal and external hemorrhoidal plexuses located in the anus. Normally they are not enlarged.
1. But due to the violation of the blood outflow in these vascular formations, thrombi may appear, they increase in size, sometimes bleed. Internal hemorrhoids sometimes come out during straining effort and bleed. The thrombosis of the external hemorrhoids is manifested by severe pain.