Goodsall's rule
Encyclopedia
Goodsall's rule relates the external opening of an anal fistula
to its internal opening. It states that the external opening situated behind the transverse anal line will open into the anal canal in the midline posteriorly. An anterior opening is usually associated with a radial tract.
Fistula
s can be described as anterior or posterior relating to a line drawn in the coronal plane across the anus
, the so called transverse anal line. Anterior fistulas will have a direct track into the anal canal. Posterior fistulas will have a curved track with their internal opening lying in the posterior midline of the anal canal
. An exception to the rule are anterior fistulas lying more than 3 cm. from the anus, which may have a curved track (similar to posterior fistulas) that opens into the posterior midline of the anal canal.
The investigation of choice for anal fistulas is magnetic resonance imaging
(MRI).
Goodsall's rule is named after David Henry Goodsall
who described it in 1900.
Anal fistula
Anal fistula, or fistula-in-ano, is an abnormal connection between the epithelialised surface of the anal canal and the perianal skin....
to its internal opening. It states that the external opening situated behind the transverse anal line will open into the anal canal in the midline posteriorly. An anterior opening is usually associated with a radial tract.
Fistula
Fistula
In medicine, a fistula is an abnormal connection or passageway between two epithelium-lined organs or vessels that normally do not connect. It is generally a disease condition, but a fistula may be surgically created for therapeutic reasons.-Locations:Fistulas can develop in various parts of the...
s can be described as anterior or posterior relating to a line drawn in the coronal plane across the anus
Anus
The anus is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, unwanted semi-solid matter produced during digestion, which, depending on the type of animal, may be one or more of: matter which the animal cannot digest,...
, the so called transverse anal line. Anterior fistulas will have a direct track into the anal canal. Posterior fistulas will have a curved track with their internal opening lying in the posterior midline of the anal canal
Anal canal
The anal canal is the terminal part of the large intestine.It is situated between the rectum and anus, below the level of the pelvic diaphragm. It lies in the anal triangle of perineum in between the right and left ischioanal fossa....
. An exception to the rule are anterior fistulas lying more than 3 cm. from the anus, which may have a curved track (similar to posterior fistulas) that opens into the posterior midline of the anal canal.
The investigation of choice for anal fistulas is magnetic resonance imaging
Magnetic resonance imaging
Magnetic resonance imaging , nuclear magnetic resonance imaging , or magnetic resonance tomography is a medical imaging technique used in radiology to visualize detailed internal structures...
(MRI).
Goodsall's rule is named after David Henry Goodsall
David Henry Goodsall
David Henry Goodsall was an English surgeon who is remembered for describing Goodsall's rule.-Biography:...
who described it in 1900.