Diseases of the Anal Canal

The anus is the final part of the gastrointestinal tract, it is about 3-4 cm long and is completely extraperitoneal. It is the continuation of the rectum which is the final part of the large intestine. It is supplied with blood from the low rectal arteries while its epithelium changes from a single-layered cylindrical to a multi-layered squamous fact that differentiates it from the rest of the large intestine.
The anus plays a particularly important role in defecating and preventing incontinence. The anus is surrounded by a network of muscles involved in the function of defecation and any damage or injury to them can lead to a significant degree of incontinence.

Those muscles are:

Internal sphincter muscle. This muscle is a continuation of the muscular layer of the rectum, surrounds the anus, is normally in contraction and is not controlled voluntarily.
External sphincter muscle that surrounds the anus behind the internal sphincter and is voluntarily controlled.
Rectal muscle which also participates in the function of continence to a lesser extent.

Diseases of the anus most often cause a poor quality of life for patients, while at the same time they are particularly painful as the area of the anus has a high number of nerves. They must always be treated by a qualified proctologist as operations in the area can lead to dangerous complications. Currently, operations on the anus are performed worldwide only by surgeons who have specialized in proctology due to the complex of the area.

Doctor Kyritsis Alexandros, General Surgeon, has specialized for three years in colorectal surgery in leading hospitals of the United Kingdom and the USA.

The diagnosis of diseases of the anus is established by the clinical examination by a specialized proctologist in combination with tests such as:

  • Proctoscopy
  • MRI scan
  • CT scan
  • Rectal manometry
  • Endorectal ultrasound
  • Proctography

The most common diseases of the anus are:


Anal cancer
Rectal prolapse
Rectovaginal fistula
Perianal fistula
Anal warts
Pilonidal sinus
Anal fissure