Flashcards in Imaging Deck (21)
What do abdominal x-rays show? When are they used?
- readily available
- often used for urgent investigation
- shows gas in abnormal places or in abnormal acts: may need upright and lateral decubitus films as well as flat plates
- can show stones and metallic fbs as well: kidney and gall bladder stones
- solid organs can be seen but not as well: can see better CT or US
Indications of abdominal x-ray? Non-indications?
- suspected bowel obstruction/perforation
- suspected intussusception
- suspected abdominal mass
- blunt abdominal trauma
-vague central abdominal pain
Normal distribution of gas in the bowel?
- intraluminal gas usually minimal
- centrally located
- numerous tight loops of small diameter (2.5-3.5 cm)
- valvulae conniventes (stack of coins)
- mix of gas and feces
- loops large in diameter (3-5 cm)
abnormal findings of gas and bowel?
- dilated loops
- air fluid levels on erect film
- intramural gas
- intraperitoneal gas
- extraperitoneal gas
When do we see ileus?
- after abdominal surgery
- bowel goes to sleep after surgery
What is an upper GI series?
- barium swallow
- uses plain fim x-ray and fluoroscopy (real time xray)
- 2 types: std barium upper GI series, double contrast upper GI series
- looks at esophagus, stomach and duodenum
Indications and CIs for upper GI series?
assessment of hiatial hernia
esophageal perforation or rupture is suspected
individuals with poor swallowing reflex (aspiration)
- risk: constipation
Indications for small bowel follow through (part of upper GI series)?
- unexplained abdominal pain
What is lower GI study? Indications, and risks?
- barium enema
- evaluates the colon: barium enema, and air contrast (double contrast) enema
colon cancer (apple core)
dx/monitor UC or crohn's disease
dx blood in stool, megacolon, constipation, diverticulitis, fistulas
Use of Abdominal CT? Indications?
-sensitive method to dx abdominal diseases (also good look at lymph nodes)
- freq used to stage and follow cancer
pts with jaundice
- shows abdominal wall - localize hernias
- dilute contrast may be used to augment the scan
- downside: expensive, high doses of radiation
When is hepatobiliary scintigraphy (HIDA scan/cholescintigraphy) used?
- in dx of problems with liver, gallbladder, or bile ducts
- radio-isotope is taken up in the liver and secreted into bile
bile duct obstruction
assessment for liver transplant
How is an abdominal U/S performed? dependent on?
preferred imaging for what?
- sound waves to visualize internal organs thru abd. wall
- can be combined with endoscopy, visualize structure in hollow organs
- can be performed quickly at bedside, no radiation, inexpensive: imaging occurs real time w/o need for sedation
influence of movements can be assessed quickly
- hampered by fat and air
- operator dependent
- limited sensitivity
- preferred imaging for RUQ pain
- useful in eval of unstable trauma pt: FAST - shows intraperitoneal fluid and also hemopericardium
- abdominal and chest CT provides more definitive info
- can visualize esophagus to duodenum
- high def white light endoscope
- minimally invasive with quick recovery: usually done under conscious or moderate sedation, most pts have a sore throat after
Indications and CIs to endoscopy?
- signs and sxs of upper GI disease
- surveillance for upper GI cancer in high risk settings
- therapeutic intervention
medically unstable/unwilling pts
head or neck surgery
Indications and CIs to capsule endoscopy?
- obscure GI bleeding
- small bowel polyps and tumors
- celiac disease
problems with this: short batter life (delayed digestion - battery will die)
- pt swallows pill containing camera, able to cover areas of small bowel that are not reachable by endoscopy
Pros and cons to flexible sigmoidoscopy?
- may be done in office
- inexpensive, cost-effective
- rduces deaths from rectal cancer
- easier bowel prep, rarely needs sedation
-detects only half of polyps
-misses 40-50% of cancers located beyond view of sigmoidoscope
- often limited by discomfort, and poor bowel prep
Indications and CIs of flexible sigmoidoscopy?
- blood in stool
- eval of colon
- medical management of colitis
- bowel perf
- acute diverticulitis
- active peritonitis
Colonoscopy used to visualize?
- rectum, colon, and distal ileum
- high def white light colonoscopy
- requires bowel prep
- uses, complications similar to upper GI endoscopy:
complications rare in dx colonoscopy
- can have bleeding, perforation, with polypectomy
Indications and CIs to colonoscopy?
- f/u colorectal cancer
- relative contra:
IBD with ulceration
What is endoscopic retrograde cholangiopancreatography (ERCP)?
- technique that uses combo of luminal endoscopy and fluoroscopic imaging to dx and tx conditions assoc with pancreatobiliary system