ABSITE ch 36 colorectal.txt

  1. 4 layers of colon wall
    mucosa, submucosa, muscularis propria, serosa
  2. portions of rectum covered in peritoneum
    anterior upper and middle 1/3
  3. circular/longitudinal interwoven inner layer of colon
    muscularis mucosa
  4. circular layer of muscle
    muscularis propria
  5. transverse bands of colon that form haustra
    plicae semilunaris
  6. three bands that run longitudinally along colon
    taenia coli
  7. approximate distance of dentate line from anus
  8. approximate distance of the anorectal ring from the anal verge
  9. vascular supply of ascending and 2/3 transverse colon
    SMA (ileocolic, right colic, middle colic)
  10. Vascular supply of 1/3 transverse, descending, sigmoid colon and upper rectum
    IMA (left colic, sigmoid branches, superior rectal)
  11. Artery that runs along the colon to connect SMA to IMA for collateral flow
    Marginal artery
  12. Short direct connection between SMA and IMA
    Arc of Riolan
  13. Origin of superior rectal artery
  14. Origin of middle rectal artery
    Internal iliac
  15. Origin of inferior rectal atery
    Internal pudendal
  16. Lymphatic drainage of superior and middle rectum
    IMA nodal lymphatics
  17. Lymphatic drainage of lower rectum
    IMA nodes, internal iliac nodes
  18. Watershed area of SMA and IMA junction near splenic flexure
    Griffith�s point
  19. Watershed area of rectum, where superior rectal and middle rectal veins join
    Sudak�s point
  20. Anal sphincter under CNS control, innervated by pudendal and S4
    External sphincter
  21. Anal sphincter under involuntary control, continuation of circular band of colon and tonically contracted
    Internal sphincter
  22. Inner nerve plexus
  23. Outer nerve plexus
  24. Distance of anal canal (from verge)
  25. distance of rectum (from anal verge)
  26. marker of transition between anal canal and rectum
    levator ani
  27. mucus secreting goblet cells in rectum
    crypts of Lieberkuhn
  28. squamocolumnar junction at anal verge
    dentate line
  29. main nutrient of colonocytes
    short-chain fatty acids
  30. treatment of infectious pouchitis
  31. Rectovesicular fascia in men (rectovaginal fascia in women)
    Denonvillier�s fascia
  32. Rectosacral fascia
    Waldeyer�s fascia
  33. Most common type of polyp (no cancer risk)
    Hyperplastic polyp
  34. Most common intestinal neoplastic polyp
    Tubular adenoma
  35. Most symptomatic polyp
    Villous adenoma
  36. % of villous adenoma that have cancer
  37. % of patients >50 with guiac positive stools that have cancer
  38. layer a dysplastic lesion must grow into to be considered invasive (in colon)
  39. normal screening for colon cancer
    flex sig q3-5y + stool guiac q1y, OR colonoscopy q10y + stool guiac q1y
  40. causes of false positive guiac
    beef, vitamin C, iron, antacids, cimetidine
  41. margins required for T1 lesion removed by colonoscopy or transanal excision
  42. margins required for T2 lesion removed by transanal excision
    much larger (APR needed)
  43. main gene mutations in colon ca (4)
    APC, DCC, p53, k-ras
  44. Most important prognostic factor in colon cancer
    Nodal status
  45. Most common site of metastasis in colon cancer
    Liver (then lung)
  46. Route of direct metastasis of rectal cancer to spine
    Batson�s plexus
  47. Subtype of colon cancer with worst prognosis
  48. Margins required in colon cancer resection
  49. best method of picking up intrahepatic mets
    intraoperative ultrasound
  50. best method to assess depth of invasion and nodal status
    rectal ultrasound
  51. reasons to do APR in patient with unresectable metastases
    pain, bleeding
  52. reasons to do an ostomy + mucus fistula in patient with unresectable metastases
  53. depth of invasion of T1 lesions
  54. depth of invasion of T2 lesions
    into muscularis propria
  55. depth of invasion of T3 lesions
    into serosa (through muscularis if no serosa present)
  56. depth of invasion of T4 lesions
    through serosa or into adjacent organs/structures
  57. N staging of colon cancer
    N0 (no nodes), N1 (1-3 nodes), N2 (4+ nodes)
  58. Rectal cancers needing XRT
    T3 or greater, or positive nodes
  59. Side effects of XRT (4)
    Vasculitis, thrombosis, ulcer, stricture
  60. % of patients with a synchronous primary lesion at time of first cancer
  61. % recurrence rate of colorectal cancer
  62. followup for colon cancer (postop)
    CEA, stool guiac q6m X3 years, then annually. Annual colonoscopy
  63. Autosomal dominant genetic defect predisposing to colon cancer
  64. Treatment of FAP patients
    Prophylactic total colectomy at age 20
  65. Locations of polyps in patients with FAP (2)
    Colonic, duodenal
  66. Genetic defect associated with colon cancers and desmoid tumors/osteomas
    Gardner�s syndrome
  67. Genetic defect associated with colon cancers and brain tumors
    Turcot�s syndrome
  68. Autosomal dominant defect associated with DNA mismatch repair gene, predisposes patients to colon cancer
    Lynch syndromes (hereditary nonpolyposis colon cancer)
  69. At least 3 1st degree relatives, over 2 generations, 1 with cancer before age 50
    Amsterdam criteria (consideration for lynch syndromes)
  70. Other cancer types found as part of Lynch II syndrome (4)
    Ovarian, endometrial, bladder, stomach
  71. Syndrome where hamartomatous polyps develop, and cancer risk is increased
    Juvenile polyposis
  72. GI hamartoma polyposis and dark pigmentation around mucous membranes
  73. Syndrome of hamartomatous polyps (no malignant potential), nail/hair atrophy, and hypopigmentation
    Cronkite-Canada syndrome
  74. Treatment of sigmoid volvulus
    Colonoscopic decompression, sigmoid resection during same admission
  75. Treatment of cecal volvulus
    Right hemicolectomy
  76. Layers of colon involved in UC
    Mucosa, submucosa
  77. Area of GI tract almost always involved in UC
  78. Anal involvement in UC?
    No (typically spares anus)
  79. Hallmarks of UC seen on colonoscopy (3)
    Mucosal friability, pseudopolyps, collar button ulcers
  80. Findings of UC on barium enema (3)
    Loss of haustra, narrow-caliber, short colon, loss of redundancy
  81. Common site of colonic perforation in UC
    Transverse colon
  82. Common site of perforation in Crohn�s
    Distal ileum
  83. Surgical indications for UC (9)
    Hemorrhage, toxic megacolon, acute fulminant UC, obstruction, dysplasia, cancer, intractability, failure to thrive, longstanding (>10y) disease
  84. Most common major morbidity after colon surgery
  85. Cancer risk with UC
    1-2% per year starting 10years after diagnosis
  86. HLA type associated with sacroiliitis and ankylosing spondylitis
  87. Conditions that improve following colectomy for UC (3)
    Ocular problems, arthritis, anemia
  88. Conditions that do not improve following colectomy for UC (2)
    PSC, ankylosing spondolytis
  89. Most common area of colon perforation after obstruction
  90. Common causes of colonic obstruction
    Cancer, diverticulitis
  91. Air in bowel wall associated with ischemia
    Pneumotosis intestinalis
  92. Pseudoobstruction of colon associated with opiate use, bedridden patients, recent surgery, infections or trauma
    Ogilvie�s syndrome
  93. Treatment of Ogilvie�s syndrome
    Colonoscopic decompression, neostigmine, cecostomy if refractory
  94. Sites of infection of entamoeba histolytica (2)
    Colon (primary), liver (secondary)
  95. Risk factors for entamoeba histolytica (3)
    Travel to Mexico, ETOH, fecal-oral transmission
  96. Treatment of entamoeba histolytica
  97. Most common site for actinomyces
  98. Treatment of actinomyces
    Tetracycline or PCN, drainage
  99. Proctitis, tenesmus, bleeding caused by chlamydia
    Lymphogranuloma venereum
  100. Herniation of mucosa through colon wall at sites where arteries enter muscular wall
  101. Most common symptom of right-sided diverticuli
  102. Most common symptom of left-sided diverticuli
    Obstruction, infection
  103. Passage of tarry stools
  104. Cause of azotemia after GIB
    Production of urea from bacterial breakdown of intraluminal blood
  105. Rate of bleed visible on arteriography
  106. rate of bleed visible on tagged RBC scan
    >0.1 cc/min
  107. perforation in colonic mucosa with adjacent fecal contamination
  108. complications of diverticulitis
    abscess, obstruction, free perforation
  109. treatment of uncomplicated diverticulitis
    flagyl/cipro, bowel rest
  110. indications for surgery for diverticulitis
    recurrent disease (2nd or more attack), obstruction, perforation, abscess, inability to exclude cancer
  111. disease presenting with fecaluria, pneumonuria
    colovesicular fistula
  112. most common cause of lower GI bleed
  113. % of diverticular bleeds that stop spontaneously
  114. first treatment of massive lower GI bleed
    angio to localize, then OR if unstable or recurrent bleeding
  115. less severe lower GIB but more likely to be recurrent
  116. % of patients with angiodysplasia that have aortic stenosis
  117. areas of colon most vulnerable to low-flow states
    splenic flexure and descending colon
  118. junction of superior rectal and middle rectal arteries
    Sudack�s point
  119. Causes of ischemic colitis
    Low flow state, ligation of IMA, embolus/thrombosis of IMA
  120. Disease with pseudomembranes, plaques, ringlike lesions seen in colon
    C. difficile colitis
  121. Enterocolitis often following chemotherapy; pneumotosis is common
    • Neutropenic typhlitis
    • Treatment of neutropenic typhlitis
    • Antibiotics. Improvement occurs when WBCs increase
  122. Bacterial infection that can mimic appendicitis in children
  123. Most common area for Hirschprung�s
  124. Most common acquired cause of Hirschprung�s
    Trypanosoma cruzi (destroys nerves)
Card Set
ABSITE ch 36 colorectal.txt
ABSITE ch 36 colorectal