How to distinguish between internal hemorrhoids, external hemorrhoids, and mixed hemorrhoids

The distinction among internal hemorrhoids, external hemorrhoids, and mixed hemorrhoids is primarily based on their locations and clinical manifestations. Internal hemorrhoids occur above the dentate line of the anal canal and are characterized by painless, intermittent bleeding with bright red blood; they may also be accompanied by protrusion of internal hemorrhoid masses. External hemorrhoids develop below the dentate line, involving the anal canal and anal margin. Their surfaces are covered by skin, and they commonly present with pain, foreign body sensation, and anal heaviness. Clinically, external hemorrhoids can be further classified into four types: inflammatory, thrombosed, varicose vein type, and connective tissue type. Mixed hemorrhoids result from the simultaneous development and merging of internal and external hemorrhoids at the same location, exhibiting combined features of both types, such as painless, intermittent rectal bleeding after bowel movements, protrusion of internal hemorrhoid masses, as well as pain and heaviness. The key to differentiating among internal hemorrhoids, external hemorrhoids, and mixed hemorrhoids lies in the differences in their anatomical locations and clinical presentations. This distinction is essential for accurate diagnosis and appropriate treatment by physicians.