Colorectal

Question 1

What are anatomical differences between internal and external haemorrhoids
- location
- histology
- vascular
- innervation

Answer 1

Internal
- above dentate line, columnar epithelium, middle rectal vein, visceral innervation

External
- subcutaneous anoderm below dentate line, modified squamous, inferior rectal vein to pudendal vein, cutaneous pain fibres

Question 2

Definition haemorrhoids
Definition haemorrhoids disease

Answer 2

Haemorrhoids - vascular arteriovenous plexuses forming two sets of anal cushions
Haemorrhoidal disease - abnormal enlargement

Question 3

Prevalence of haemorrhoids?
Gender/Age

Answer 3

4.5% symptomatic
M=F
45-65 yo

Question 4

Pathophysiology haemorrhoidal disease

Answer 4

• loss of fibromuscular attachments through repeated strain
• prolapse of cushions
• impaired venous return -> venous engorgement, venous stasis, venous hypertension
• above prompting pain

Question 5

Classification Internal Haemorrhoids

Answer 5

Grade I - bleeding no prolapse
Grade II - prolapse with strain, spontaneous reduction
Grade III - prolapse with strain, manual reduction
Grade IV - persistent prolapse

Question 6

Efficacy of:
- rubberband ligation
- sclerotherapy
- HAL

Answer 6

Rubber band: 70% at 5 years
Sclerotherapy: 70%
HAL: 5% 1 year grade III 25% 1 year grade IV (reduced with mucopexy)

Question 7

GOALS Haemorrhoidectomy

Answer 7

removal diseased anal cushion
ligation vascular pedicle
preservation underlying sphincter
preservation adequate skin bridges

Question 8

Definition anal fissure

Answer 8

Ulceration squamous epithelium of the anal canal distal to dentate line

Question 9

Pathophysiology anal fissure

Answer 9

Driven by cumulative effect of
- local mucosal trauma, pain increases sphincter contraction
- hypertonic internal sphincter: drives relative mucosal ischaemia, driven by reduced NO

Chronic fissure - cycle of non healing and repeated trauma

Question 10

Commonest location for anal fissure

Answer 10

Posterior - 80-90%
- relative deficiency external sphincter
- higher resting anal pressures
- reduced density of vascular supply

Question 11

What is different about anterior fissures

Answer 11

• more commonly in women
• more commonly due to external anal sphincter injuries
• therapies directed at hypertonic sphincter less likely to be effective

Question 12

Efficacy medical sphincterotomy
- GTN
- diltiazem
- Botox

Answer 12

GTN - 70% 6 weeks, 50% recurrence but second course treats half those
Diltiazem - 70% with reduced side effects seen with GTN
Botox - 75% with temporary incontinence in 5-10%

Question 13

Classification anal fistula

Answer 13

Intersphincteric - 45%
Trans-sphincter - 30%
Supra-sphincteric - 20%
Extra-sphincteric - 5%

Question 14

Non-neoplastic polyp

Answer 14

Inflammatory
Hyper-plastic
Harmartoma

Question 15

What clinical tool can be used to assess UC severity, and what are they components?

Answer 15

Mayo Score
- frequency of stools
- rectal bleeding
- mucosal appearance at endoscopy
- physician rating disease activity