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150 Cards in this Set

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  • Back

what is the accuracy of unenhanced CT to diagnose appendicitis


what is the nl bowel wall thickness distended and contracted?
1-2 mm, 3-4 mm
at the GE junction the stomach may measure up to?
2 cm
benign pathologic small bowel thickening usually does not exceed what length?
1 cm
benign wall thickening is caused by?
ibd, ischemia,inramural hemorrhage
neoplastic wall thickening is caused by?
when distended the wall of the esophagus should not exceed?
3 mm
what is the most common benign tumor of the esophagus?
what are the 3 general causes of esophagitis?
what is the main ct finding in esophagitis?
long segment of circumferential wall thickening >5mm
what is Boerhaave's Syndrome?
spontaneous rupture of the esophagus associated with violent vomiting
the gastric wall should not exceed ___ when distended?
5 mm
what is the best CT scan finding for gastritis
thickened gastric folds, MC in the antrum
what is Scirrhous Carcinoma (Linitis Plastica)
diffuse wall thickening with luminal narrowung seen in gastric carcinoma
What is the MC site for GI Lymphoma?
stomach NHL B-cell type
What is a Cajal Cell?
The common precursor cells for GIST (stromal tumors) arise
Where do most GIST arise from?
the Muscularis Propria in the stomach
What differentiates a GIST from a leiomyosarcoma?
presence of KIT CD117 protein- tyrosine kinase growth receptor factor
What are the 2 MC causes for gastric varices?
portal htn, spenic vein thrombosis
What is the hallmark finding for splenic vein thrombosis?
gastric varices without esophageal varicies
What are the anatomic ends of the duodenum?
pylorus and ligament of Treitz
What Ligament divides the right and left lobes of the liver?
What vessels supply the liver?
portal vein 75%, Hepatic artery 25%
What medication stops peristalsis and dilates bowel wall?
Small bowel lumen and wall thickness should not exceed?
2.5 cm, 3 mm
Wall thickening greater than 1.5 cm is c/w?
mesenteric mass
What is visually different from THe jejunum compared to the ileum?
jejunal loops are feathery with distinct folds. ileum loops are featherless with thin walls
Where do Carcinoid tumors MC occur?
Appendix 50% and Small Bowel 20%
Intussusception is associated with what metastatic tunor to the bowel?
Melanoma, fibrosing CT characteristic
What is the hallmark finding in Crohn's Disease?
Circumferential thickening of the bowel wall maybe as thick as 3 cm. esp the terminal ileum
What is the Comb Sign?
produced by hyperemic thickening of the vasa recta is a sign of active disease
What is a paralytic ileus?
dilitationof proximal and distal small bowel without a transition zone.
What is a complete SBO?
dilitation of proximal small bowel with a distinct transition zone to collapsd distal bowel
What is a partial SBO?
falls between sbo and ileus. the proximal bowel is less dilated and the transition zone is less distinct
What causes most SBO?
What is the MC malignancy seen in the Mesentery?
The normal appendix does not exceed what dimension?
6 mm
What is Gardner's Syndrome?
AD assoc with multiple adenomatous polyps, osteomas,sebaceous cysts and desmoid tumors
Appendicoliths are seen in what percentage of pts with appendicitis?
What is the name of the classification system for colon cancer?
Where does colon ca metastisize to?
liver, lung, and adrenal
What %age of pts who have undergone bowel resection for ca will have recurrent disease?
70-80% within 2 years
Describe the difference in bowel wall thickening beween Crohns, UC, and Pseudomembranous colitis?
UC 7-8 mm
Crohns 10-20 mm
Pseud. Colitis up to 30 mm
What is Typhilitis?
infection of the cecum and ascending colon. classically in pts who have leukemia undergoing chemo
What are the MC areas of the colon affected by Ischemic Colitis?
watershed areas, splenic flecture and recto sigmoid
What are the CT hallmarks of Toxic Megacolon?
dilitation of the colon > 5 cm, thinning of wall, pneumatosis, and perforation
What are the 4 categories of Pneumatosis Intestinalis?
Bowel Necrosis, Mucosal Disruption, Increased mucosal permeability, and Pulmonary conditions
What is the MC type of volvulus?
Where does the apex o the twisted bowel point to in Sigmoaid and Cecal Volvulus?
Sigmoid: LLQ
What is a Cecal Bascule?
Folding of the Cecum rather than a twisting. it gets displaced into the central abdomen
What is the significance of the Marginal Artery of Drummond?
anastomoses the (IMA) with the (SMA). It is sometimes absent, as an anatomical variant.
What is the Median Arcuate Ligament Syndrome?
the ligament inserts low and thus crosses the proximal portion of the celiac axis, causing compression and sometimes resulting in abdominal pain usually in women worse during expiration
What is a Nutcracker Esophagus?
finding of increased pressures during peristalsis, diagnosis made when pressures exceed 180 mmHg; this has been likened to the pressure of a mechanical nutcracker
What does the CREST Syndrome stand for? What disease is it associated with?
Scleroderma ;
Raynaud's syndrome
Esophageal dysmotility
What is Plummer Vinson Syndrome?
aka Paterson-Brown-Kelly syndrome or sideropenic dysphagia is a disorder linked to severe, long-term iron deficiency anemia, which causes (dysphagia) due to (esophageal webs)
What is the luminal diameter for Shatzki's ring and symptoms?
<12mm 100% symptomatic
13-20 mm 50%
>20 assymptomatic
How many sec does it take the food to traverse the esophagus?
8 to 10 sec
What is Passavant's Cushion?
A prominence on the posterior wall of the nasal pharynx formed by contraction of the superior constrictor of the pharynx during swallowing.
Name the 2 lateral Diverticulum?
Lateral and Killian-Jamieson
Where is a Zenkers Diverticulum always located?
posterior and superior or through the Cricopharyngeus muscle. never below
What is Rigler's Sign?
double wall sign, is seen on an x-ray of the abdomen when air is present on both sides of the intestine; a Rigler's sign is present when air is present on the inside (lumenal side) and the outside (peritoneal side
Caroli disease?
communicating, cavernous ectasia of the intrahepatic bile ducts
rare, autosomal recessive
usually detected in childhood or early adulthood
no cirrhosis or portal HTN
predisposed to calculus formation
recurrent cholangitis ==> liver abscesses ==> death
increased risk of cholangiocarcinoma
a/w medullary sponge kidney (renal tubular ectasia) in 80%
primary sclerosing cholangitis?
a/w IBD (50%), usually UC
M > F
peak age 20-30 y/o
chronic inflammation + fibrosis of all bile ducts
stricture, obstruction, abscess ("string of beads")
intramural pseudo-diverticula
cholangioCa (10%!!)
dilatation proximal to stricture may signal Ca

cholangioCa (diffuse form)
primary biliary cirrhosis (PBC)
AIDS-related cholangitis (? d/t CMV)
medullary sponge kidney?
"renal tubular ectasia"
dilatation & cyst formation of collecting tubules in renal pyramids
Ca2+ ==> medullary nephrocalcinosis
not hereditary; males (2:1)
usually bilateral
renal tubular acidosis (RTA)
Caroli disease
parathyroid adenoma
hypertrophic pyloric stenosis
Ehlers-Danlos syndrome
ipsilateral hemihypertrophy
Gardner syndrome?
autosomal dominant
adenomas --> colon Ca (tx: colectomy)
periampullary Ca
soft-tissue lesions
sebaceous cysts
subQ fibromas, leiomyomas, lipomas
bony lesions
osteomas (esp. in sinuses)
cortical thickening
dental abnormalities (caries, extra teeth, odontomas)
75% in kids <2 y/o
ileocolic (75%), ileo-ileocolic (15%)
90% idiopathic
leading point: lymphoid tissue (possibly increased 2' to enteritis)
in older kids + adults (ileo- or colocolic)
Meckel diverticulum
Peyer's patches
large mesenteric nodes
"currant jelly" stools
"coiled spring" on BE
** transient intussusception: a/w spruePseudokidney sign
Solid and Papillary Endothelial Neoplasm
pancreas divisum?
unfused ducts of Wirsung and Santorini
incidence: 5-11%
21-45% get pancreatitis,
possibly due to stenosis of the minor ampulla
Boerhaave syndrome?
complete, transmural laceration of esophagus
spontaneous (retching, EtOH)
2' to endoscopy, trauma, vagotomy, FB
sx: chest pain, shock, dyspnea, cyanosis
grave prognosis
M > F
usually on LEFT
uncommonly sub-diaphragmatic

see also:
esophageal trauma
V sign of Naclerio
V sign of Naclerio?
V-shaped collection of air
in mediastinum + along diaphragm
indicates pneumomediastinum + pneumothorax
seen in Boerhaave syndrome
Mallory-Weiss syndrome?
mucosal gastric tear
only 10% are purely esophageal:
most are at GE junction or proximal stomach
M > F, associated with retching, EtOH
massive hematemesis, abd pain
Dx: endoscopy
Rx: IA vasopressin
Normal extrinsic impressions on the esophagus are made by what 3 structures?
Left Mainstem Bronchus
Left atrium
Name the 3 compartments of pharynx and their anatomic landmarks
Nasopharynx: base of skull to soft palate
Oropharynx: Soft palate to the Hyoid bone
Hypopharynx: Hyoid bone to the cricopharyngeus muscle
At what level do you find the cricopharyngeus muscle?
Hamartomatous polyps accur in what syndrome? Are they malignant?
Peutz-Jeghers, no
Where is a Meckel's located?
antimesenteric border of the ileum, up to 2m from the ileocecal valve. 2 to 8 cm in length
What is the vascular hallmark of splenic vein thrombosis?
gastric varices without esophageal varices
What distinguishes GIST's from leiomyomas/sarcomas?
Tyroaine kinase growth factor (CD117)
desmoplastic (fibrotic) tumors
carcinoid of SB or colon
Hodgkin's lymphoma
scirrhous gastric Ca
What is the tx for GIST?
Imatinib (Gleevec), tyrosine kinase inhibitor
necrotizing inflammation of the colon in neutropenic patients

* cecum ("typhlon" in Greek) most frequent site
* patients with leukemia, terminal lymphoma, aplastic anemia, cyclic neutropenia
* symptoms: abdominal pain, diarrhea

xray findings:

* soft-tissue mass in right lower quadrant
* thumbprinting due to bowel wall edema
* intramural gas
* bowel wall thickening

ultrasound findings:

* thickening of bowel mucosa
* intraluminal fluid
* pericecal fluid
* abdominal abscess
dromedary hump
extra mass of normal tissue found only on the lateral portion of the left kidney

* normal variant

* "It's not a tumor."
- Arnold Schwartzenegger in Kindergarten Cop
Monckeberg's Medial Calcific Sclerosis
form of arteriosclerosis is characterized by calcific deposits in the media of small to medium-sized muscular arteries. Because the intima is not involved, the lumen is not compromised, and there is little clinical consequence to the pure form of this abnormality. However, some patients also have atherosclerosis affecting the same vessel.
GI-tract target lesion
* metastatic melanoma

* 1' neoplasm
o spindle cell tumor (benign or malignant)
o lymphoma
o carcinoid
o carcinoma

* metastasis
o breast Ca
o lung Ca
o renal Ca
o Kaposi's sarcoma

* eosinophilic granuloma
* ectopic pancreas
target lesions of liver/spleen
* lymphosarcoma (incl. Kaposi sarcoma)
* melanoma
Gastroschisis represents a herniation of abdominal contents through a paramedian full-thickness abdominal fusion defect. The abdominal herniation is usually to the right of the umbilical cord. No genetic association exists. A gastroschisis usually contains small bowel and has no surrounding membrane. The herniated bowel is not rotated and is devoid of secondary fixation to the posterior abdominal wall.

Gastroschisis usually is detected in the second trimester using antenatal sonography. The maternal serum alpha-fetoprotein (AFP) level is elevated in 77-100% of mothers. The mortality rate is approximately 17%. Surgical repair should be offered within the first day after delivery to avoid infection. The outcome is no different in infants delivered in tertiary obstetric centers than in infants delivered in smaller peripheral hospitals, although delivery within easy access of a neonatal surgical unit is advised. Cesarean delivery is performed in many mothers of fetuses with gastroschisis, although this does not convey any advantage over vaginal delivery.
mphalocele is an anterior abdominal wall defect at the base of the umbilical cord, with herniation of the abdominal contents. The herniated organs are covered by the parietal peritoneum. After 10 weeks' gestation the amnion and Wharton jelly also cover the herniated mass.

Omphaloceles are associated with other anomalies in more than 70% of the cases. Most associated anomalies are chromosomal. The anomaly is detected during routine ultrasonographic examination of the fetus or during an investigation of an increased alpha-fetoprotein (AFP) level.
asplenia / polysplenia syndromes
probably different degrees of the same disorder

* asplenia (Ivemark syndrome, bilateral right sidedness)
o more severe
o right lung lobar anatomy bilaterally, bilateral eparterial bronchi
o associated with cardiac, GI/GU and situs anomalies
+ TAPVR(~100%),ECD(85%)and many others
o Howell-Jolly bodies - RBC inclusions

* polysplenia (bilateral left-sidedness)
o left lung lobar anatomy bilaterally, bilateral hyparterial bronchi
o multiple spleens/splenules
o bilateral SVCs, azygos continuation of IVC
o associated with cardiac(less common than in asplenia), GI/GU and situs anomalies
adenomyomatosis of gallbladder
type of hyperplastic cholecystosis

* increase in number and height of mucosal folds
* secondary to hyperplasia of mucosal and muscular elements
* Rokitansky-Aschoff sinuses (intramural diverticula)

* 5% of all cholecystecomies
* > 35 years; M:F = 1:3

associated with:

* gallstones in 25-75%
* cholesterolosis in 33%


* "comet-tail" artifact seen by US - cholesterol crystals in RA sinses
* may have smooth sessile fundal mass in GB
* may have an "hourglass" configuration with transverse septum
* "pearl necklace gallbladder" on OCG
Rokitansky-Aschoff sinuses
small outpouchings of gallbladder mucosa that extend through the muscularis layer

* may be congenital
* a/w adenomyomatosis of gallbladder
most common cause of mechanical SBO in patients who have had previous abdominal surgery
carcinoid syndrome
vasodilation 2' to serotonin elaboration
bronchial carcinoid
SB carcinoid

indicates liver mets (liver would otherwise break down serotonin secreted by 1' lesion)
carcinoid tumor
"rule of one-third"
1/3 of GI carcinoid in SB
1/3 ==> mets
1/3 have 2nd malignancy
1/3 multiple

90% from distal ileum or appendix
90% of appendicial tumors

desmoplastic reaction ==> kinking + angulation of SB
angio: intensely vascular lesions

arise from seratonin producing intraepithelial endocrine cells, namely the Kulchitsky’s cells of the crypts of Lieberkuhn
What %age of pts with carcinoid tumor have carcinoid syndrome?
10%, if the syndrome is occuring there must be mets to the liver
Hypertrophic Pyloric Stenosis
Not usually seen until 3 weeks
projectile vomiting
olive sign
wall > 3mm
elongated >18 mm
liver tumors are primarily supplied by which vessel?
hepatic artery
The liver gets it's primary blood supply from?
Portal Vein
retroperitoneal liposarcoma
most common primary retroperitoneal tumor
rarely arises from lipoma
95% of all fatty retroperitoneal tumors

40-60 years; M>F
most radiosensitive sarcoma (32% 5-year survival)

contrast enhancement
mixed density (fat and soft tissue elements)
pseudocystic pattern: water density secondary to volume averaging
angio: hypovascular; no vessel dilation, capillary staining, laking

sites for liposarcoma:
lower extremity 45%
abdominal cavity and retroperitoneum 14%
trunk 14%
upper extremity 8%
head and neck 7%
What vessel primarily supplies liver tumors?
Hepatic Artery
diaphragmatic eventration
upward displacement of abdominal contents secondary to a congenitally thin hypoplastic diaphragm

* location:
o anteromedial on right
o total involvement on the left
o R:L = 5:1

* findings:
o small diaphragmatic excursions
o often lobulated contour

see: elevated hemidiaphragm
elevated hemidiaphragm
* phrenic nerve paralysis: invasive Ca, trauma, aneurysm
* idiopathic: right-sided in males, poss. viral
* subphrenic disease: abscess, peritonitis; pancreas, GB
* neurological disease: polio, peripheral neuritis, zoster
* splinting: chest wall injury
* myotonia congenita
* pulmonary infarct
* eventration
* gaseous distension of stomach or colon

* DDxChest fluoro may be helpful to rule out paralysis.
* Basal ("subpulmonic") effusion may mimic elevation.
What %age of gallstones are radiopaque?
peliosis hepatis
* benign, intrahepatic vascular disorder
o a/w benign + malignant liver tumors
o possible vasodilatory response to sex hormones
o (?) clinical significance

* multiple endothelium-lined, blood-filled spaces
* communicate with sinusoids

* angio (parenchymal phase):
o multiple round collections of contrast in liver (3 - 15 mm)

* DDx:
o focal nodular hyperplasia
o hypervascular mets
o cavernous hemangiomata
3 normal extrinsic impressins on the esophagus
aortic arch
left main bronchus
left atrium
intussusception adults vs peds
adults ileal-ileal
peds ileal-colic
Most frequent congenital anomaly of GI tract
Meckel Diverticulum
Treatment of midgut volvulus
Ladd procedure: Reduction of volvulus, division of mesenteric bands, placement of small bowel on right and large bowel on left and appendectomy.
"Moulage sign"
(cast) characteristic of sprue
Reversal of jejunoileal fold pattern
Thickened proximal small bowel folds with micronodularity (1-2 mm) & low density mesenteric adenopathy (near fat HU)
buzz words for ulcerative colitis
lead pipe colon
collar button ulcers
toxic megacolon
backwash ilietis
sclerosing cholangits
buzz words for crohns
apthous ulcers
string sign
creeping fat
comb sign
Treatment of Ulcerative colitis
Sulfasalazine, steroids, azathioprine
Methotrexate, LTB4 inhibitors
Total or proctocolectomy, Brooke or continent ileostomy (Kock pouch)
Treatment of Crohn's
Mucosal biopsy to diagnose
Steroids, azathioprine, mesalamine
Metronidazole, antibody treatment
Resection of diseased bowel
Strictureplasty, primary fistulotomy
Extensive ahaustral colonic dilatation, air-fluid levels, mucosal islands or pseudopolyps
Toxic Megacolon
"Accordion sign":
Trapped enteric contrast between thickened colonic haustral folds. a/w pseudomembranous colitis
Treatment of pseudomembranous colitis
Mild cases: Discontinue offending antibiotic therapy
Severe cases
Metronidazole (drug of choice) or oral vancomycin
Fulminant & toxic megacolon: Colectomy
Pneumatosis, mesenteric venous gas, symmetric bowel wall thickening or thumbprinting on CT
ischemic colitis
Watershed segments of colon
Splenic flexure: Junction of superior mesenteric artery (SMA) & inferior mesenteric artery (IMA) (Griffith point)
Rectosigmoid: Junction of IMA & hypogastric artery (Sudeck point)
Left colon: Typical in elderly with decreased perfusion
Right colon: Young patients due to decreased collateral blood supply; chronic renal failure patients
cecal vs sigmoid volvulus
cecal points toward luq
sigmoid points toward ruq
Treatment of cecal volvulus
Colonoscopy to reduce volvulus
Complicated cases: Surgery (cecopexy, cecostomy, resection)
Treatment of sigmoid volvulus
Proctoscopic/colonoscopic decompression of obstruction ± stabilization via rectal tube insertion
70-80% success rate
Nonoperative + operative
Decompression, mechanical cleansing & elective sigmoid resection
Complicated cases
Surgical emergency
Water-soluble contrast enema to rule out underlying colon cancer
Congenital, multifocal, segmental, saccular dilatation of intrahepatic bile ducts.
Communicating cavernous biliary ectasia
Caroli disease:
caroli's disease vs syndrome
syndrome includes hepatic fibrosis
"Central dot" sign:
Strong, enhancing, tiny dots (portal radicles) within dilated intrahepatic bile ducts on CECT.
seen in caroli's dz
2 types of hyperplastic cholecystosis
Adenomyomatosis vs cholesterolosis
Adenomyomatosis: Fundal, diffuse or mid-body GB wall thickening with intramural high amplitude echoes & "comet tail" reverberation artifacts
Cholesterolosis: Multiple GB polyps
CECT: Thickened GB wall (segmental or diffuse); often brisk enhancement of wall post-contrast; cystic nonenhancing spaces within GB wall corresponding to intramural diverticula
DDX Fibrolamellar Carcinoma
conventional HCC, intrahepatic cholangiocarcinoma,
focal nodular hyperplasia (FNH),
hepatocellular adenoma,
cavernous hemangioma.
what is a normal gastric band phi angle
A normal gastric band should have a phi angle (angle between the spinal column and the gastric band) of 4°-58°.
what are some complications to gastric banding?
gastric banding is associated with complications; the most common of which include band misplacement, band slippage, band herniation, perforation, pouch dilation, and erosion of the gastric wall.
what is the normal position of a gastric band in relationship to the diaphragm and what is a phi angle?
The gastric band should be 4–5 cm below the diaphragm with a phi angle of 4°–58°.
what should the stoma size be in gastric banding?
The stoma should be 3–4 mm in diameter.
Risk factors for the development of cholangiocarcinoma include?
clonorchiasis, primary sclerosing cholangitis, Caroli disease, intrahepatic stone disease, chronic liver disease/cirrhosis, Thorotrast exposure, and choledochal cysts.
What are the classic findings of gallstone ileus? What is the triad
Classic findings of gallstone ileus are pneumobilia, small bowel obstruction, and ectopic gallstone (Rigler triad).
mcc well-circumscribed heterogeneously enhancing mass arising from the abdominal wall.
Solitary fibrous tumor
paragangliomas in which locations are a/w parasympathetic or sympathetic system?
Paraganglia associated with the parasympathetic system are located in the head, neck, and anterior mediastinum. Paraganglia associated with the sympathetic system are located in the posterior mediastinum and retroperitoneum.
paragangliomas are a/w which diseases?
Paragangliomas can be sporadic or hereditary in association with multiple endocrine neoplasia type 2 A and B, tuberous sclerosis, neurofibromatosis, von Hippel-Lindau, and Carney’s triad.
What is Carneys triad?
Carney’s triad (malignant gastrointestinal stromal tumors, pulmonary chondroma, and extra-adrenal paragangliomas).
What make up the portal triad
portal vein
hepatic artery
bile duct
DDX Periportal Edema
Systemic hypervolemia or overhydration
Passive hepatic congestion
Acute hepatitis
Hepatic trauma
Dilated intrahepatic ducts (Imaging findings can mimic periportal edema.)
DDX Calcified splenic nodules
disseminated pneumocystis carinii infection.
Clinical history can help narrow the differential diagnosis. Other findings of portal hypertension such as portosystemic collateral vessels favor GGB, Gamma Ganda Bodies

mc congenital abnormality of the gi tract

meckel's diverticulum
classic findings of Gardner syndrome
Colonic adenomatous polyps,
extracolonic adenomatosis,
osteomas, and
desmoid tumors
MC liver tumor


Fat-containing FNHs may demonstrate unusual features such as

larger size,
multifocality, and
absence of the central scar.

cystic mass with internal septations
biliary cystadenoma
cystic hcc
hepatic abscess
cyst aspiration
if cystadenoma remove bcs it cannot be distinguished from a cystadenocarcinoma

What is Blind Loop Syndrome?

Blind-loop syndrome, a complication of small-bowel diverticulosis, occurs when food and waste are trapped within the diverticula, which promotes an overgrowth of bacteria that leads to malabsorption and diversion of nutrients to the bacteria. Patients often present with enteritis symptoms along with steatorrhea, malnutrition, anemia, and weight loss.

Most adrenocortical carcinomas are functional, what hormone do they secrete?


The most specific findings for adrenal malignancy are?

Irregular margins.

Thick enhancing rim?

What are the histological subtypes of an appendiceal Mucocele?

four main histologic subtypes: retention cyst, mucosal hyperplasia, cystadenoma, or cystadenocarcinoma. The former two classifications are nonneoplastic entities with the latter representing neoplastic mucin-secreting tumors. The diagnosis in this case of “low-grade mucinous neoplasm” is an entity between cystadenoma and cystadenocarcinoma in which cells have penetrated the appendiceal wall. Low-grade mucinous neoplasms have the highest risk of developing into pseudomyxoma peritonei.