Anorectal Disorders Flashcards
Give examples of congenital ano-rectal abnormalities
Imperforate anus
Uro-Genital Fistulae
Hirschprung’s Myenteric Plexus Deficiency
Give examples of acquired ano-rectal abnormalities
Haemorrhoids
Fissure
Abscess
Fistula-in-ano
Ulceration
Cancer
Control of Continence
What is the cause of haemorrhoids?
Venous plexus congestion around the anal canal
What is the aetiology of haemorrhoids?
Unknown
Associated with straining or constipation
What are the symptoms of haemorrhoids?
Bright red rectal bleeding
Pruritis ani
Mucus discharge
What is the treatment of haemorrhoids?
Band ligation (if above the dentate line)
Injection scleropathy
Stapled anopexy (https://www.youtube.com/watch?v=Xv2y8XtGCCY)
What is the cause of anal fissures?
Trauma or ischaemia
What is an anal fissure?
Superficial mucosal tear most commonly in the midline posteriorly
What are the symptoms of anal fissures?
Pain on defacation
Minor bleeding
Mucus discharge and pruritis
Odematous skin tag / ‘sentinal pile’ may be present next to the fissure
Treatment for anal fissures requires relaxing the internal anal sphincter, how is this done?
Medical: Topical nitric oxide, diltiazem calcim bocker
Surgical: Internal lateral sphincterotomy
What happens as a result of the tension of the internal anal sphincter being too high?
The internal anal sphincter is always under tension, also known as resting pressure. If that pressure becomes too high, a fissure may form or an existing one may not heal.
In surgical anal sphincterectomy - an incision reduces the resting pressure, allowing the fissure to heal.
Where do perianal abscesses develop?
Inbetween the internal and external anal sphincters and may point at the perianal skin
Where do ischiorectal abscess occur?
Lateral to the sphincters in the ischiorectal fossa
How do ischiorectal abscesses usually develop?
Infection of the anal glands by normal intestinal bacteria
Crohn’s disease is sometimes responsible
What are the symptoms of perianal fistulae?
Extreme perianal pain, fever and discharge of pus
What can happen as a result of rupture of anorectal abscess?
Development of fistulae
May be superficial or may track through the anal sphincters to reach the rectum
How are abscesses treated?
Surgical incision and drainage
What is a fistula in ano?
An anal fistula can be described as a narrow tunnel with its internal opening in the anal canal and its external opening in the skin near the anus.
Where do anal fistula form?
Anal fistulae originate from the anal glands, which are located between the internal and external anal sphincter and drain into the anal canal. If the outlet of these glands becomes blocked, an abscess can form which can eventually extend to the skin surface. The tract formed by this process is a fistula
What are the complications associated with anal fistula?
Painful
Irriitating because of the drainage of pus - formed stools can also pass through the fistula
Starting point for systemic infection
What are the symptoms of anal fistula?
pain
swelling
tenderness
fever
unpleasant odor
Pus / serous fluid / faeces discharge
Describe the lay - open surgical procedure indicated for superficial fistulae
Fistula is cut open
Packed on a daily basis for a short period of time to ensure that the wound heals from the inside out.
May cause problems with continence depending on where the fistula lies in terms of the sphincter muscles.
Not indicated in patients with fistula that span the full distance between the internal and external sphincters
What is a seton stitch?
It is a thread that is placed through the fistula and out the anus - allows the infection to drain and heal, without damaging the sphincter muscles
What percentage of colorectal cancers are in the rectum and anus?
Rectum: 16%
Anus: 3%
What are the possible imaging modalities for the colorectum?
Colonoscopy with or without x-ray screening
Colonography (x-Ray procedure)
MRI guided colonoscopy, MRI component allows the shape of the endoscope to be displayed on screen in real time
What is treatment for anal squamous cancer?
Radiotherapy
What is the treatment for rectal adenocarcinoma?
Neo adjuvant ChemoRad
Laparoscopic Resection
What are the causes of anal ulceration?
Crohn’s Disease
Malignancy
Syphilis “Chancre”
Nicorandil
What are common causes of faecal incontinence?
Severe diarrhoea
Anorectal disease - haemorrhoids, rectal prolapse, Crohn’s
Neurological conditions - spinal cord/cuada equina legions
Dementia
