Perianal disease Flashcards
What is the dentate line
When the mucosa gathers into longitudinal folds which contain anal glands (Secrete mucus)
What is above the dentate line derived from
Embryological hindgut
What is below the dentate line derived from
Ectoderm
What is the epithelium above the dentate line
Columnar epithelium
What is the epithelium below the dentate line
Non keratinising squamous epithelium
What is the epithelium in the anal verge
Keratinizing squamous epithelium
Blood supply above dentate line
Superior rectal artery/vein (derived from IMA)
Blood supply below dentate line
Inferior rectal artery/vein (derived from internal pudendal artery)
Lymphs above dentate line
Internal iliac lymph nodes
Lymphs below dentate
Superficial inguinal lymph nodes
Nervous innervation above dentate line and presentation
Inferior hyper gastric plexus (stretch ulnae)
Nervous innervation below dentate line and presentation
Pudendal nerve (pain, temp, touch and pressure)
Lications of anal cushions
3 o clock
7 o clock
11 o’clock
What is a haemorrhoid
Abnormal swelling and vascular engorgement of normal anal cushions
Investigations with presentations
DRE exam
Protoscopy (for internal haemorrhoids)
What is a anal fissure
Longitudinal tear in the anal canal mucosa
Where do anal fissures usually present
6 o’clock
12 oclock
What are anal fissures associated with
Constipation
Crohns
Symptoms of anal fissures
Severe pain post defecation
Fresh red bleeding
Itching
PR excruciation
Exam findings of anal fissure
Break or ulcer in the mucosa
Acute management of anal fissure
Dietery modification
Laxatives, instillagel and topical diltiazem or GTN cream
Chronic management of anal fissure
Examination under anaesthesia and injection of botox (relaxes)
Lateral sphincterotomy
What is a peri anal abscess
Collection of pus in anal region
Pathology of peri anal abscess
Cyryptoglandular infection
Bacterial overgrowth
Usually e.coli, bactericides spp. And enterococcus spp
Presentation of perianal abscess
Painful, hot, red lump in perianal region
Discharging pf pus
Sepsis
What investigations may some patients require with PA abscess
CT or MRI
Management of perianal abscess
surgical incision and drainage of abscess
Antibiotics not good because can’t penetrate into it
What is a fistula in and
Abnormal connection between the anal canal and peri-anal skin
Risk factors of fistula in ano
IBS
Systematic disease - HIV, TB, diabetes
Trauma
Pelvic radiation
Presentation of fistula in ano
Peri-anal abscess
Intermittent or continuous discharge of pus, blood or mucuous from the perineum
On examination of fistula in ano
Small opening in perineum
Some granulation tissue that may discharge on palpation
Thickening fibrous tract palpable in the skin
What is the Goodsall’s rule
Where the fistula is decides on treatment
e.g.
If patient lying down and you drew a line going through middle of the anus going horizontally-
- External opening above (anterior) to the line is connected through the internal opening by a short straight line
- External opening below (posterior) to the line has a curved or horseshoe tract
Investigation of a fistula in ano
Exam using proctoscopy or exam under anaesthesia
Curved tracts usually get gluteal or pelvic MRI
Managemt of fistula in ano
Drain abscess
Seton- an elastic band put through external opening into internal opening and tied to make a loop that allows sepsis to drain, preventing abscess.
Fistulotomy- laying open of the tract including the overlying skin and/or muscle.
