Chapter 37 - Anal & Rectal Flashcards
What is the arterial supply to the anus?
Inferior rectal artery
What is the venous drainage above the dentate line? Below?
Above: Internal hemorrhoid plexus
Below: External hemorrhoid plexus
Hemorrhoid plexus locations?
Left lateral, right anterior, right posterior
Symptoms of external hemorrhoids?
Pain when they thrombose, swelling, itching
Symptoms of internal hemorrhoids?
Bleeding or prolapse
Grades of prolapse of internal hemorrhoids?
Primary: slides below dentate w/ strain
Secondary: prolapse that reduces spontaneously
Tertiary: Prolapse that has to be manually reduced
Quaternary: not able to reduce
Treatment for hemorrhoids?
Stool softeners, fiber, sitz baths
Surgical indications for hemorrhoids?
Recurrent disease (bleeding), thrombosis, large external component
Banding for internal or external hemorrhoids?
Internal only
Rectal prolapse begins how far from the anal verge?
6-7cm
What causes rectal prolapse? Risk factors?
Pudendal neuropathy and laxity of the anal sphincters; increased with females, straining, diarrhea, previous pregnancy, redundant sigmoid colons
Treatment for rectal prolapse?
High-fiber diet
Rectosigmoid resection (Altmier) transanally
LAR or rectopexy
Virus associated with condylomata acuminata?
HPV
Laser surgery
What causes anal fissure?
Split in the anoderm
Where are anal fissures located?
90% in posterior midline
Symptoms of anal fissure?
Pain and bleeding after defecation; chronic ones will see a sentinel pile
Medical treatment for anal fissure? Surgical?
Medical: sitz baths, bulk, lidocaine jelly, stool softeners
Surgical: lateral subcu internal sphincterotomy
Most serious complication of anal fissure surgery?
Fecal incontinence
Contraindications to surgery for anal fissure?
If secondary to Crohn’s or UC
Drainage procedure for perianal, intersphincteric, and ischiorectal abscesses?
Through skin (all below the levator muscles)
Drainage for supralevator abscesses?
Transrectally
Treatment for pilonidal cyst?
Drainage and packing; follow0up surgical resection of cyst
Treatment for fistula in ano?
Unroof fistula and eliminate the primary opening with rectal advancement flap; do not need to excise the tract
What is Goodsall’s rule?
Anterior fistulas connect with rectum in straight line; posterior fistulas go toward midline internal opening in rectum
Definition of simple rectovaginal fistula?
Secondary to infection or obstetrical trauma, low to midvagina, <2.5cm
Treatment for simple rectovaginal fistula?
Many heal spontaneously; transanally unroof and place rectal mucosa advancement flap
Definition of complex rectovaginal fistula?
Secondary to inflammatory bowel disease, XRT, neoplasm, or high in vagina, or >2.5cm
Treatment for complex rectovaginal fistula?
Abdominal or combined approach; resection and reanastomosis with placement of colostomy, need good tissue for anastamosis
Types of anal incontinence? Treatment?
Neurogenic: no good treatment
Abdominoperineal descent: damage to levator ani muscle and anus falls below levators, stretches the pudendal nerves; high fiber diet, limit to 1 bm/day, sphincteroplasty if related to trauma (childbirth)
Anorecatal problems associated with AIDS? Characteristics?
Kaposi’s sarcoma: nodule with ulceration
CMV: shallow ulcers, similar presentation as appendicitis
HSV: #1 rectal ulcer
B cell lymphoma: can look like abscess or ulcer
What type cancer found in the anal canal (above dentate line)?
Squamous cell CA, basaloid, mucoepidermoid, adenocarcinoma, melanoma
Treatment for squamous cell CA of anal canal?
Chemo: Nigro protocol, chemo - 5FU and mitomycin, XRT) NOT surgery
Cure rate for anal squamous cell CA?
80%
Treatment for adenocarcinoma of the anal canal?
APR; WLE if <1/3 circumference, limited to submucosa, well differentiated, no vascular/lymphatic invasion; needs 1cm margin; postop chemo/XRT
Treatment for melanoma of the anal canal?
APR; margin dictated by depth of lesion standard for melanoma
What accounts for most deaths due to anal canal melanoma?
Hematogenous spread to the liver and lung early
Most common symptom of melanoma of anal canal?
Rectal bleeding
What type of cancers are found in anal verge (below dentate line)?
Squamous cell CA, basal cell CA, Bowen’s disease, Paget’s disease
What is the treatment for squamous cell CA of the anal verge?
WLE for lesions <3cm, can get 0.5cm margin; APR for larger lesions or if sphincter involved
Treatment for basal cell CA of anal verge?
WLE usually sufficient; need 3mm margins; rare need for APR
What is Bowen’s disease?
Intraepidermal squamous cell CA
Associated conditions with Bowen’s disease?
1 or more primary internal malignancy or primary cancer of the skin with internal mets
Treatment for Bowen’s disease?
Local therapy, WLE with clear margins
What is Paget’s disease of anal verge?
Intraepidermal apocrine gland CA, slow growing, positive PAS stain
Treatment for Paget’s disease?
WLE with clear margins; groin dissection for positive nodes
Where do nodal mets from anal/rectal cancer go?
Superior and middle rectum: IMA nodes
Lower rectum: primarily IMA nodes, internal iliac nodes
Upper 2/3 of anal canal: internal iliac and pelvic nodes
Lower 1/3 of anal canal: inguinal nodes
