A perianal haematoma is a collection of blood under the surface of the skin at the edge of the anal opening.
Perianal haematomas are caused by a traumatic rupture of a small blood vessel in this area due to high pressures resulting from straining. Many people with a perianal haematoma can recall lifting something heavy, moving house, carrying suitcases or children, severe coughing or straining with constipation shortly before they notice that there is something wrong in their anal area. Similarly, perianal haematomas are commonly seen in people working out at gyms, lifting weights, etc.
The perianal haematoma presents as a painful lump at the edge of the anal opening (anal verge). They can vary in size from a centimeter to the size of a golf ball, and are usually quite painful. The pain will last for a week to ten days. Patients take all sorts of over the counter medications for these but there is not much good evidence that anything helps.
A perianal haematoma has a natural course that it will follow pretty much regardless of what the patient does. Eventually, the pain will lessen and stop, and the patient will be left with firm lump which will gradually shrink and disappear over the course of 3 months or so.
In some cases, it is best to have the haematoma excised by a Prof Memon. If the haematoma is large and he sees it within the first 48 hours, excising it will lessen the pain and speed the entire course of healing. If, however, he sees you later, when the haematoma is starting to settle and get less painful, he may decide to leave it be and it will settle.
Perianal haematomas are often misdiagnosed as haemorrhoids or external haemorrhoids.
Perianal haematomas must be distinguished from true haemorrhoids or abscesses.
Because perianal haematomas are usually the result of straining, they can recur.