Anorectal disorders - NOT PRIORITY Flashcards
Epithelium of rectum/anus
Rectum - columnar
Anal canal - stratified squamous
Defaecation is controlled by what nerves
Parasympathetic fibres of S2-S4
What line divides the anal canal into upper and lower parts
Pectinate line
Arterial supply above pectinate line (rectum and upper anal canal)
Superior rectal artery (branch of IMA)
Arterial supply below pectinate line (lower anal canal) (2)
Inferior rectal artery (branch of internal iliac artery)
Middle rectal artery
What is the inferior rectal artery a branch of
Internal iliac artery
Venous drainage above pectinate line
Superior rectal vein
Venous drainage below pectinate line
Inferior rectal vein
Nerve supply above pectinate line
Inferior hypogastric plexus (parasympathetic)
Nerve supply below pectinate line
Inferior anal nerves (sensory + motor)
Function of anal canal
Faecal continence
Capacity of rectum
200-300ml faecal contents
Anorectal disorders are divided into what 2 categories
Congenital
Acquired
Anorectal disorders usually present with what 3 things
Pain
Haemorrhage
Dysfunction
Name 3 congenital anorectal disorders
Hirschprung’s disease - baby can’t defaecate because no myenteric plexus
Imperforate anus
Uro-genital fistulae
Name acquired anorectal disorders (7)
Peri-anal haematoma Rectal prolapse Haemorrhoids Anal fissure Peri-anal abscess Fistula-in-ano Anal cancer
What are haemorrhoids
Swellings contains swollen blood vessels within the anal canal
Normal anatomical and functional component of the anal canal; they become pathological only when they cause symptoms
Symptoms (2) /signs (2) of haemorrhoids
Rectal bleeding
Perianal pain/discomfort
Anal pruritus
Anal mass/ perianal lesion
Treatment of haemorrhoids (8)
Diet + lifestyle change - more fibre, fluids, exercise
Steroid cream
Grade 2/3 haemorrhoids:
- Rubber band ligation
- Sclerotherapy - injecting something to numb and harden the haemorrhoid
- infrared photocoagulation
- haemorrhoid arterial ligation (blood vessels supplying haemorrhoid are stitched closed)
- stapled haemorrhoidopexy
Grade 4
-haemorrhoidectomy
What is a stapled haemorrhoidopexy
Part of the anorectum [last section of the LI], is stapled, so haemorrhoids are pulled back into rectum; reduces the supply of blood to the haemorrhoids, which causes them to gradually shrink
How does infrared photocoagulation treat haemorrhoids
passing electric current to cause the blood supplying the haemorrhoid to coagulate so haemorrhoid can shrink
What is an anal fissure
Split in the skin of the distal anal canal characterised by pain on defecation and rectal bleeding
Much worse than haemorrhoids
Symptoms/signs of an anal fissure (3)
Pain on defaecation
Blood in stool/toilet paper
Anal spasm
Risk factors of anal fissure (2)
Hard stool
Pregnancy
Treatment of anal fissure (4)
Topical glyceryl trinitrate
Topical diltiazem
If resistant to above:
botulinum toxin injection
surgical sphincterotomy - cutting some of sphincter muscle to relax it
What is a peri-anal abscess
Collection of pus near the anus usually due to infection of small anal glands
Treatment of perianal abscesses
Surgical incision and drainage
What may be underlying if perianal abscesses persistently fail to heal after incision and drainage
Fistula formation
How can fistulas result from abscesses
Abscesses can extend to the skin surface forming a tract (FISTULA) between the anal gland and the skin (internal opening in anal canal and external opening in skin) if the abscess doesn’t heal properly
Anal fistula treatment (3)
Fistulotomy - cutting open fistula so it heals as a flat scar
Seton suture - to keep fistula open and allow pus to drain
Fistula plug after seton suture
Anal ulcer could be a feature of what GI disease
Crohn’s
Anorectal cancer is usually what type of tumour
Squamous cell carcinoma
Definitive diagnosis of anorectal cancer
Biopsy
Investigations of anal cancer (4)
Anoscopy + biopsy
Anal ultrasound
CT abdo/pelvis - to look for metastases
Treatment of anal cancer
fluorouracil (CHEMO) + mitomycin (CHEMO) + radiotherapy
so CHEMORADIOTHERAPY
Treatment of rectal adenocarcinoma (2)
Neoadjuvant chemoradiotherapy
Surgical resection
