Anorectal Diseases

Question 1

What is rectal prolapse?

Answer 1

Protrusion of rectum through anal canal

Complete (full thickness) vs partial prolapse (mucosal only)

Question 2

Difference between complete and partial rectal prolapse

Answer 2

Complete - full-thickness bowel wall, circumferential rings

Partial - Intussusception of mucosa, radial folds

Question 3

Who gets rectal prolapse?

Answer 3

Bimodal distribution

<3yo - male/female ratio equal, will resolve on own with development of pelvis/sacrum, self-limiting

> 70yo - 80-90% female, multifarious, constipation, concurrent pelvic organ prolapse, chronic constipation, psychiatric comorbidities

Question 4

Causes/Anatomical effects

Answer 4

Defecatory disorders, multiparous, neurological or psychiatric comorbidities (chronic constipation)

Deep pouch of Douglas, associated enterocele, straining issues, wide pelvic inlet and redundant, non-fixed rectosigmoid, pelvic floor stony, patulous anus

Denervation or stretch injury to anal canal - pudendal neuropathy, low resting anal tone

Question 5

What testing to perform for rectal prolapse?

Answer 5

Colonoscopy vs barium enema - look for lead point/cancer
Cinedefacography - if unable to see on physical exam (hidden prolapse)
Colonic transit studies if report severe constipation - Ddx colonic inertia preoperatively

Question 6

Signs/symptoms of rectal prolapse

Answer 6

Mucous drainage, uncomfortable sensation sitting on mass within anal canal, prolapse during defecation with eventual prolapse with most activities, bleeding - possible ulceration of mucosa at leading edge, pressure, fecal incontinence

Question 7

When would rectal prolapse be an emergency?

Answer 7

Becomes incarcerated/strangulated if normal tone to anal sphincter or the prolapsed rectum has become very edematous

Urgent surgery

Question 8

Two approaches to surgical treatment of rectal prolapse - why would you choose one over the other?

Answer 8

Abdominal vs perineal approach

Choice mainly due to patient’s functional status

Question 9

Types of abdominal techniques for rectal prolapse?

Answer 9

Sutured rectopexy
Mesh rectopexy
Resection rectopexy

Question 10

Perineal approaches to rectal prolapse

Answer 10

Perineal rectosigmoidectomy (Altmeier)
Mucosal sleeve resection (Delorme) 
Anal encirclement (Thiersch)

Question 11

Describe anal encirclement approach to rectal prolapse (Thiersch procedure)

Answer 11

Can be done with local anesthetic; high risk patients
Two longitudinal incisions made lateral to external anal sphincters
Kelly clamp used to tunnel submucosal layer around anus
Mesh pulled around to encircle anus
Calibrate tension with digit within anal canal - snug to stop prolapse but loose enough to allow passage of stool

Does not eliminate redundant rectum, nor stop prolapse into anal canal
Fecal impaction common occurrence
Lots of post-op pain
Eventual mesh erosion - septic and mechanical complications high
No longer used

Question 12

Describe Delorme procedure

Answer 12

• Excising mucosal and submucosal layers and placating outer muscular layer of rectum
• Rectum prolapsed through anal canal using Babcock clamps
• Submucosal layer injected with epinephrine solution 2cm above the dentate line - dissection, decrease bleeding
• Circumferential incision made 2cm above dentate line - through mucosa and submucosa
• Electrocautery used to dissect submucosal layer circumferential along length of prolapse - elevate off muscle layer of rectum
• Extent of dissection determined by placing traction on rectum delivering entire prolapse through anal canal until tension noted
• Absorbable sutures placed in muscular layer creating accordion effect
• Stripped mucosa resected after sutures placed circumferentially
• Sutures tied down and anastomoses completed

High recurrence rate (15-30%) - within 2-3yrs
Best for mucosal prolapse

Question 13

Anal fissure treatment

Answer 13

Fiber, stool softeners, sits baths
NTG or Nifedipine ointment
Botox injection
Lateral internal sphincterotomy

Question 14

Surgeries available for Anal fistula

Answer 14

Seton
Fistula plug
Endorectal advancement flap - prefer for rectovaginal
LIFT procedure
Lay open fistulotomy

Question 15

Grade of internal hemorrhoids

Answer 15

1: bleeding, no prolapse
2: prolapse but spontaneously reduce after BM
3: require manual reduction
4: Non-reducible

Question 16

Causes of fecal incontinence

Answer 16

Structural:

• Obstetric injury
• Rectal prolapse
• Weak puborectalis
• Injury to pudendal nerve

Functional:

• Impaired anorectal sensation
• Impaction with overflow incontinence

Psychological factors

Question 17

Treatment fecal incontinence

Answer 17

• Supportive measures/lifestyle
• Loperamide, diphenoxylate/atropine
• Biofeedback therapy
• Plugs, bulking agents
• Sacral nerve stimulation
• Sphincteroplasty

Question 18

Why avoid resection rectopexy after Altemeier if recurrence?

Answer 18

Risk ischemia to distal segment

Question 19

Anatomy of rectum and anus at cell level

Answer 19

Rectum - columnar
Anus - squamous cell
Transitional zone - cuboidal epithelium

Question 20

Internal sphincter

Answer 20

Involuntary
Thickened continuation of circular smooth muscle of rectum
Autonomic NS

Question 21

External sphincter

Answer 21

Voluntary
Inferior extension of puborectalis muscle
Striated muscle
Somatic inner action

Question 22

Levator ani muscles

Answer 22

Iliococcygeus
Pubococcygeus
Pelvic floor w/ inner action from 4th sacral nerve

Question 23

Lymphatic drainage of rectum/anus

Answer 23

Superior/middle rectum - IMA nodes
Lower rectum/upper anal canal - superior rectal lymphatic (to IMA) + internal iliac nodes
Anal canal distal to dentate line - dual drainage to inguinal nodes and internal iliac nodes

Question 24

Internal and external hemorrhoid definitions

Answer 24

Internal: Above dentate line, columnar epithelium, dilation of mucosal veins of superior rectal plexus

• Left lateral
• Right posterolateral
• Right anterolateral

External: dilated veins from inferior hemorrhoid all plexus below dentate, squamous epithelium (anoderm)