GI System Flashcards
what refers to a primary cancer arising from stomach
gastric cancer
what are the different formations of gastric cancer
focal mass/polyp w/wo ulceration, focal wall thickening with mucosal irregularity, gas-filled ulceration, wall thickening with loss of normal rugal folding pattern, or any combination of these
what is one of several idiopathic inflammatory bowel diseases
Crohn’s disease
why is Crohn’s described as ‘idiopathic’
because it has no known cause
when is crohn’s visible via sectional imaging
during periods of active inflammation
what do majority of crohn’s patients present with
inflammation/thickening of small bowel
where is the thickening/inflammation of crohn’s especially seen at
terminal ileum
in what % of cases of Crohn’s is there abscess formation also present
15-20%
what can also appear abnormal during periods of active inflammation of crohn’s
mesentery
what is a mechanical occlusion of small bowel
small bowel obstruction (SBO)
what can SBO be caused by
numerous conditions including: volvulus, mass, ileus, stricture, Crohn’s, etc.
what is the single most important indication of SBO
gross distention of small bowel
what is most common cancer of GI tract
colo-rectal cancer
what is the other ways colo-rectal cancer is described as
colon cancer and rectal cancer
what does the vast majoritiy of colo-rectal cancers arise from
pre-existing polyp neoplasms
as the polyp undergoes additional mutations, it eventually transforms to a what condition
malignant
where can colo-rectal cancer be visualized in GI tract
throught large bowel and rectum
what are other complications that masses due to colo-rectal cancer be associated with
large bowel obstruction, abscess, or inflammation
what is a condition of large bowel inflammation
colitis
what are the 2 categories colitis can be grouped into
ischemic colitis and ulcerative colitis
what is secondary to vascular insufficiency
ischemic colitis
like crohn’s what is an idiopathic inflammatory condition
ulcerative colitis
what is importion to differentiate between crohn’s and ulcerative colitis
clinical history
what appears as notable bowel wall thickening
both ischemic colitis and ulcerative colitis
what are the other pathologies associated with ischemic and ulcerative colitis
an obstruction or ascites
what is essentially inflammation of appendix
appendicitis
appendicitis is especially common in what patients
young
when appendix is visible, it appears how
enlarged, inflamed, and often surronded with reactive fluid in interstitial fat
what is reactive fluid
standing
severe cases of appendicitis is accompanied by what
abscess formation
what will a ruptured appendix show
free air and or free fluid in abdomen
in what % of all appendicitis diagnoses is an appendicolith the cause
7-15%
what is an appendicolith
stone is appendix
liver cancer is grouped into two categories, what are they
hepatocellular carcinoma and hepatic metastasis
what is the primary liver cancer
hepatocellular carcinoma
what does liver cancer appear as
small or large focal walled masses in liver parenchyma
what is primary liver cancer fed by
hepatic artery and therefore enhances during atrial phases
what is metastatic liver cancer usually supplied by
hepatic portal vein and therefore enchances during portal phase of contrast enhancement
what are the different ways liver cancer can present
unifocal, multifocal or diffusely infiltrative at time of presentation
what does unifocal and multifocal mean
unifocal - one mass
multifocal - multiple masses
what does diffusely infiltrative mean
entire liver
secondary liver cancer can also present how
one or many lesions
what is necessary to distinguish between primary or met liver cancer
clincal correlation and or biopsy
how much more common is metastatic liver lesions than primary tumors
20 times more common
what can appear throughout the body
hemangiomas
what are benign mass compoased of highly vascular tissue
hemangiomas
in theliver, what is important to distinguish between
benign mass from malignant processes such as liver cancer or abscess
what is most common benign tumor of liver
hemangioma
what do hemangimas in liver present as
focal mass with or without rim enhancement
what has extremely slow blood flow and therefore enhance with contrast much later than normal liver tissue
hemangiomas
delayed imaging through the mass is valuable in characterizing the lesion when what are suspected
hemangiomas
what is the suggested time delay when hemangiomas are suspected
5-15 min
what is the common endpoint for a number of conditions affecting the liver
cirrhosis
what are the most common causes of cirrhosis
alcoholism, IV drug abuse, and hepatitis
liver cells injured by cirrhosis conditions cause what
fibrosis and diffuse structural changes in liver
what modality is especially sensitive in early diagnosis of cirrhosis
no modality
with disease progression, liver cirrhosis is most commonly seen as what
surface and parenchymal nodularity
fatty infiltrates are what
sometimes visible
what is common in later stages of cirrhosis disease
perihepatic fluid accumulation
what is a common consequence of trauma to RUQ
liver laceration
the liver what is fractured flowed by hemorrhage and sometimes infarct
parenchyma
wpecialty imaging does not generally show a _______ itself but effects of it
laceration
what are the effects of a liver laceration
atypical/non-uniform contrast perfusion through the organ and limited or absence of contrast perfusion throught organ, contrast extravasation in our around organ, and hematoma in area of organ
what is a tissue deprived of blood
infarct
how much of an organ can an infarction involve
entire (global) or a portion of an organ (segmental)
what are the different factors as to why blood supply to the liver or portion of liver may be inhibited
thrombus, emboli, foreign object, stenosis, laceration, and arterial dissection
what will contrast enhanced scans show when dealing with infarcts
areas of limited contrast perfusion in both chronic and acute infarcts
what will non-contrast imaging of infarcts show
areas of ischemia
what is a malignant condition arising from cells of lymph system
lymphoma
what can lymphoma be further subdivided into
hodgkin, T cell, and B cell lymphoma
what can mainfest through the body in essentially every body system
lymphoma
lymphoma is especially relevant to what imaging
spleen imaging
majority of malignant spleen lesions are what
lymphoma
in sectional imaging, lesions appear as in other body structures with one or more low density lesions throughtout what
the spleen
with the exception of what imaging, the parenchyma of a normal spleen should have a purely homogenous appearance in both CT and MRI
arterial
what is the most common organ injury from blunt trauma to abdomen
spleen laceration
does specialty imaging show lacerations itself
no
what does specialty imaging show when dealing with lacerations
effects of laceration
what are the effects of lacerations
atypical/non-uniform contrast perfusion through organ, limited or absence of contrast perfusion through organ (infarct), contrast extravasation in or around organ, and hematoma in area of organ
spleen infarction may involve how much of organ
global or segmental
what is most common primary cancer of pancreas
ductal adenocarcinoma
what is the percent of ductal adenocarcinomas
90%
the prognosis of what is very poor
ductal adenocarcinoma
the large majority of primary pancreatic neoplasms affect what of the pancreas
head
how does pancreatic cancer appear as
a poorly defined mass
in CT pancreatic cancer is __________________ while it is _______________ in MR
hypodense, hypointense
what are pancreatic neoplasms slow at
taking up contrast, therefore do not enhance as quickly as normal pancreatic tissue
what refers to any form of inflammation to pancreas
pancreatitis
what is most common cause of pancreatitis
alcohol abuse
what are other causes of pancreatitis
gallstones, metabolic abnormalities, malnutrition, and hereditary pancreatitis
what does pancreatitis appear as in sectional imaging
visibly inflamed and surrounded by reactive fluid accumulation
what can severe cases of pancreatitis cause
ascites throughout abdomen
what does chronic pancreatitis often form
pockets of pancreatic juices
what are those pancreatic juices called
pancreatic pseudocysts
what do pseudocysts have
fibrous wall and fluid contents
what is a relatively uncommon adenocarcinoma
gallbladder cancer
in what % of cases is it related to gallstones
70-90%
what are the 3 presentations of gallbladder cancer
intraluminal mass, diffuse wall thickening, and mass completely replacing the gallbladder
if mass is present, it will sometimes be engulfing what
gallstones or an area of necrosis
what is also common when imaging GB adenocarcinomas
gallbladder enlargement, obstruction, inflammation, and intrusion into surrounding structures
what is a common condition more often known as gallstones
cholelithiasis
what are gallstones generally composed of
cholesterol
if the stone moves into the cystic duct or common bile duct, what is the condition called
choledocholithiasis
if an obstruction forms and the gallbladder becomes inflamed the condition is described as
cholecystitis
what can be easily seen with sectional imaging
gallstones
what are additional complications often seen when imaging gallstones
inflammation and distention of gallbladder (cholecystitis), wall thickening, pericholecystic reactive fluid and fat stranding
