Chapter 37: Anus and Rectum

Question 1

arterial supply to the anus

Answer 1

inferior rectal artery

Question 2

venous drainage of the anus

Answer 2

above the dentate is internal hemorrhoid plexus and below the dentate is external hemorrhoid plexus

Question 3

hemorrhoidal plexuses

Answer 3

• left lateral - right anterior - right posterior

Question 4

• can pain when the thrombosis - distal to the dentate line, covered by sensate squamous epithelium; can cause pain, swelling and itching

Answer 4

external hemorrhoids

Question 5

cause bleeding or prolapse

Answer 5

internal hemorrhoids

Question 6

tx: hemorrhoids

Answer 6

fiber and stool softeners (prevent straining); sitz baths

Question 7

tx: thromboses external hemorrhoid

Answer 7

lance open (if > 72 hours) or elliptical excision (if

Question 8

surgical indications for hemorrhoids:

Answer 8

recurrence, thrombosis multiple times, large external component

Question 9

hemorrhoids: can be resected with elliptical excision

Answer 9

external hemorrhoids

Question 10

type of internal hemorrhoids that can be banded

Answer 10

can band primary and secondary internal hemorrhoids - do not band external hemorrhoids (painful)

Question 11

surgery required for what type of internal hemorrhoids

Answer 11

surgery for tertiary and quaternary internal hemorrhoids - 3 quadrant resection - need to resect down to the internal anal sphincter (do not go through it)

Question 12

post op management of tertiary and quaternary internal hemorrhoids

Answer 12

sitz baths, stool softener, high-fiber diet

Question 13

where does rectal prolapse start?

Answer 13

starts 6-7 cm form anal verge

Question 14

what causes rectal prolapse?

Answer 14

secondary to pudendal neuropathy and laxity of the anal sphincters

Question 15

risk factors for rectal prolapse

Answer 15

increased with female gender, straining, chronic diarrhea, previous pregnancy, and redundant sigmoid colons

Question 16

what layers of the rectum are involved in rectal prolapse?

Answer 16

prolapse involves all layers of the rectum

Question 17

medical treatment: rectal prolapse

Answer 17

high-fiber diet

Question 18

surgical tx: rectal prolapse

Answer 18

• perineal rectosigmoid resection (altemeier) transanally if patient is older and frail - low anterior resection and pexy of residual colon if good condition patient

Question 19

caused by a split in the anodrem - 90% in posterior midline - causes pain and bleeding after defection; chronic ones will see a sentinel pile

Answer 19

anal fissure

Question 20

medical tx: anal fissure

Answer 20

sitz baths, lidocaine jelly, and stool softeners (90% heal)

Question 21

surgical tx: anal fissure

Answer 21

lateral subcutaneous internal sphincterotomy

Question 22

most serious complication of surgery for anal fissure

Answer 22

fecal incontinence

Question 23

what do you worry about with lateral or recurrent anal fissures?

Answer 23

worry about inflammatory bowel disease

Question 24

can cause severe pain - risk factors: antibiotics, cellulitis, DM, immunosuppressed or prosthetic hardware

Answer 24

anorectal abscess

Question 25

anorectal abscess: can be drained through the skill (all are below the elevator muscles)

Answer 25

perianal, intersphincteric, and ischiorectal abscesses

Question 26

anorectal abscess: can form horseshoe abscess

Answer 26

intersphincteric and ischiorectal abscesses

Question 27

anorectal abscess: need to be drained transrectally

Answer 27

supralevator abscesses

Question 28

- sinus or abscess formation over the sacrococcygeal junction; increased incidence in men - tx?

Answer 28

pilonidal cysts tx: drainage and packing; follow-up surgical resection of cyst

Question 29

do not need to excise the tract - often occurs after anorectal abscess formation

Answer 29

fistula-in-ano

Question 30

what is goodsall's rule for fistula-in-ano?

Answer 30

- anterior fistulas connect with anus/rectum in a straight line - posterior fistulas go toward a midline internal opening in the anus/rectum

Question 31

tx: fistula-in-ano (lower 1/3 of the external anal sphincter)

Answer 31

fistulotomy (open tract up, curettage out, let it heal by secondary intention)

Question 32

tx: fistula-in-ano (upper 2/3 of the external anal sphincter)

Answer 32

rectal advancement flap

Question 33

most worrisome complication of treatment for fistula in ano

Answer 33

risk of incontinence - you want to avoid damage to the external anal sphincter so fistulotomy is not used for fistulas above the 1/3 of the external anal sphincter

Question 34

tx -\> rectovaginal fistulas: - simple (low to mid-vagina)

Answer 34

tx: trans-anal rectal mucosa advancement flap - many obstetrical fistulas heal spontaneously

Question 35

tx -\> rectovaginal fistulas: - complex (high in vagina)

Answer 35

abdominal or combined abdominal and perineal approach usual; resection and reanastomosis of rectum, close hole in vagina, interpose omentum, temporary ileostomy

Question 36

tx: neurogenic anal incontinence (gaping hole)

Answer 36

no good treatment

Question 37

chronic damage to levator ani muscle and pudendal nerves (obesity, multiparous women) and anus falls below levators

Answer 37

abdominoperineal descent

Question 38

tx: abdominoperineal descent

Answer 38

high-fiber diet, limit to 1 bowel movement a day; hard to treat

Question 39

tx: obstetrical trauma leading to anal incontinence

Answer 39

anterior anal sphincteroplasty

Question 40

what is anal cancer associated with?

Answer 40

xrt and hpv

Question 41

above dentate line

Answer 41

anal canal

Question 42

below dentate line

Answer 42

anal margin

Question 43

what are the different types of squamous cell carcinoma in the anal canal?

Answer 43

epidermoid CA mucoepidermoid CA cloacogenic CA basaloid CA

Question 44

anal cancer: - symptoms: pruritus, bleeding, and palpable mass

Answer 44

squamous cell CA

Question 45

tx: squamous cell CA - anal cancer

Answer 45

nigro protocol (chemo-XRT with 5FU and mitomycin), not surgery - cures 80% - APR for treatment failures or recurrent cancer

Question 46

tx: adenocarcinoma - anal cancer

Answer 46

APR usual; WLE if

Question 47

3rd most common site for melanoma

Answer 47

anal cancer (skin and eyes #1 and #2)

Question 48

how does melanoma spread?

Answer 48

1/3 has spread to mesenteric lymph nodes - hematogenous spread to the liver and the lung is early and accounts for most deaths

Question 49

what is symptomatic melanoma of the anal cancer associated with?

Answer 49

significant metastatic disease

Question 50

anal melanoma: most common symptom

Answer 50

rectal bleeding

Question 51

anal melanoma: appearance

Answer 51

lightly pigmented or not pigmented at all

Question 52

tx: anal melanoma

Answer 52

APR usual; margin dictated by depth of lesion standard for melanoma

Question 53

anal cancer below dentate line - have better prognosis than anal canal lesions

Answer 53

anal margin lesions (below dentate line)

Question 54

- ulcerating, slow growing; men with better prognosis - metastases: go to inguinal nodes

Answer 54

squamous cell cancer - anal margin lesions

Question 55

sx: anal margin lesions (squamous cell CA)

Answer 55

WLE for lesions

Question 56

anal margin lesions: squamous cell CA - primary tx for lesions \> 5cm, if involving sphincter or if positive nodes

Answer 56

chemo-XRT (5-FU and cisplatin) - try to preserve the sphincter here and avoid APR

Question 57

anal cancer: central ulcer, raised edges, rare metastases

Answer 57

basal cell CA

Question 58

tx: anal cancer - basal cell CA

Answer 58

WLE usually sufficient, only need 3-mm margins; rare need for APR unless sphincter involved

Question 59

nodal metastases: superior and middle rectum

Answer 59

IMA nodes

Question 60

nodal metastases: lower rectum

Answer 60

primarily IMA nodes, also to internal iliac nodes

Question 61

nodal metastases: upper 2/3 of anal canal

Answer 61

internal iliac nodes

Question 62

nodal metastases: lower 1/3 of anal canal

Answer 62

inguinal nodes

Question 63

Classification for hemorrhoids

Answer 63