Radiology Flashcards
Upper GI tract
Oropharynx
esophagus
stomach
duodenum
lower GI tract
jejunum ileum large bowel rectum appendix liver gallbladder pancreas spleen mesentery peritoneum
Common clinical indications for abdominal xray
- Pain **most common
- dysphagia
- change in bowel movement
- trauma
- abnormal labs
- pre/post operative
- cancer/metastasis work up
- bloating/abd distention
Emergent clinical indications for abd xray
- hemorrhage
- perforation
- infection
GI imaging modalities
- radiograph/plain film
- fluoroscopy
- ERCP
- US
- CT
- Nuclear medicine
Two types of intraluminal contrast
barium
gastrografin
Intraluminal contrast with barium
- pros and cons
Pro
- better visibility
- can be given in great quantity
- use if risk for aspiration
Con
- can cause mediastinitis or peritonitis if perforation exists
Intraluminal contrast with gastrografin
Pro
- water soluble, safe/better to use if perforation is suspected
- often used post-op bowel sx to evaluate for leak/extravasation
- therapeutic effect as an enema for constipation
Con
- can cause pneumonitis if aspirated
X-rays
- interpreted based on what
- less dense vs. more dense
- relative densities
- more white = more dense
- more black = less dense
5 densities in xrays
- air: black
- fat: gray
- soft tissue/fluid: white
- calcium: more white
- metal: bright white
Common abdominal xray views
- upright and supine: most common
- KUB (kidney, artery, bladder)
- Lateral decubitus
When use upright and supine xray view
air fluid levels / free air (ex bowel obstruction)
when use KUB xray view
gall stones kidney stones masses perforations obstruction
when use lateral decubitus xray view
free air
Fluoroscopy
- define
uses X-rays to evaulate GI tract, usually with intraluminal contrast such as barium
Fluoroscopy common exams/indications
- Dysphagiagram (swallow study): poor oral intake, aspiration, post-stroke eval
- esophagram: difficulty/pain swallowing, post traumatic/post-op perforation
- Upper GI: anatomy (ped), reflux, pain, obstruction, perforation
- SBFT (small bowel follow-through): obstruction, IBD, post op anatomy
- Enema: anatomy, cancer, IBD, post-op, constipation
what see on normal esophagram
- smooth contour
- striations
Anatomical feature that is very important to duodenal placement in body
Ligament of Treitz
- double fold of peritoneum
- marks boundary between upper/lower GI tract (junction duodenum and jejunum)
- pathology = malrotation/partial rotation
how to tell difference between jejunum and ileum
- jejunum is feathery
- ileum is longer, smoother
ACBE
Air contrast barium enema
- insert contrast into lrg. bowel to coat lumen, then fill with air.
- look for strictures, polyp, etc.
- often orders after “failed” colonoscopy due to anatomic abnormality of transverse colon
ERCP
Endoscopic retrograde cholangio-pacreatography
- evaluate biliary and pancreatic ducts
how is an ERCP done
- endoscope is passed through esoph/stomach into the duodenum
- catheter is inserted into common bile duct, dye is injected in retrograde fashion to opacify the ducts
- evaluate anatomy and observe for strictures or filling defects caused by stones, cancer, masses
- an also retrieve stones
US
- pro & GI anatomy seen well
- con & GI anatomy not seen well
Pro:
- no radiation, inexpensive, real time images
- Liver, gallbladder, spleen, pylorus, appendix
Con:
- tech dependent, sometimes limited visibility
- not good for bile duct, pancreas, small bowel, appendix
*appendix depends on the tech
US
- evaluated in terms of what
- three results and what they indicate
- echogenicity
- Hyperechoic: fat, air, calcium (bone, stone), metal
- iso-echoic: soft tissue
- hypo-echoic: fluid, vessels
CT
- pro
- con
Pro: better contrast than US, high spacial resolution, reproducable
Con: radiation, contrast often needed
CT evaluated on terms of what? Units?
- density (bc xray)
- Hounsfield units
CT planes
- transverse
- frontal
- sagittal
Nuclear Medicine
- two common tests
- Cholescintigraphy
- GI bleed scan
Cholescintigraphy
- HIDA scan
- directly assess biliary system
- indirectly assess liver
- inject body with agent, body processes it, helps understand if there is liver or gallbladder etc dz.
GI bleed scan
- used to eval site of suspected or known GI bleeding
- active bleeding must be occurring…
- can detect subtle bleeds
HIDA and Gi bleed scan images
didn’t go into detail in class, it’s in the slides
Esophagus common GI pathology
- Zenker’s
- Barrett’s
- Cancer
Zenker’s Diverticulum
- describe
- posterior esophageal out pouching at level of hypopharynx
Zenker’s Diverticulum
- sx
- modality
- halitosis, dysphagia, regurgitation
- esophagram
Zenker’s Diverticulum
- findings
- diverticulum arising midline posterior from esophagus at level of hypopharynx. may be transient
Barrett’s esophagus/esophageal cancer
- describe
metaplasia of esophageal squamous cells caused by chronic reflux. Precursor for adenocarcinoma
Barrett’s esophagus/esophageal cancer
- sx
- modality
- usually asymptomatic
- esophagram
Barrett’s esophagus/esophageal cancer
- findings
- long segment stricture in mid to lower esophagus, irregular folds, large solid ulcer
- irregularity and shouldering indicative of cancer
Hiatal hernias
- describe
four types
I: GE junction above diaphragm
II: Ge in normal location, gastric fungus above diaphragm
III: mixed I and II
IV: gastric volvulus -stomach above diaphragm and twisted on axis
Hiatal hernia
- sx
- modality
- reflux, dysphagia
- esophagram/upper GI
Hiatal hernia findings
- look at slides for images :)
Peptic ulcer
- describe
- ulcers secondary to gastric acid
- risk: H. pylori, NSAIDS, steroids, ZE syndrome
Peptic ulcer
- sx
- modality
- epigastric pain
- upper GI, CT for perforation complications
peptic ulcer
- findings
- barium out pouching pocket with radiating folds of mucosa towards/away from ucler
- Hamptom’s line
Malignant ulcer
- findings
- barium fills ulcer but NO out pouching, does not protrude beyond gastric border
- large flat ulcers
- Carman Meniscus sign - rolled edges are convex toward the lumen
Perforated Ulcer
- modality
- finding
- CT
- tiny amt of air in non-dependent peritoneum at midline (free air)
- ulcer within stomach with air along sight of perforation
Pyloric stenosis
- define
- sx
- hypertrophy of gastric pylorus musculature
- projectile non-bilious vomitting, usually 4-12 weeks of age
pyloric stenosis
- modality
- findings
- US
- abnormal msrmnts and non-visualization of gastric content passing through pylorus
Malrotation
- define
absence of Ligament of Treitz to fix duodenal-jejunal junction in left upper abdomen
Malrotation
- sx
- modality
- duodenal obstruction or volvulus (twisting of bowel)
- Upper GI
Malrotation findings
- duodenal-jejunal junction does not cross midline to left of the left pedicle and does not reach level of duodenal bulb
Midgut volvulus
- define
- sx
- complication of mal rotation: obstruction and ischemia. Generally in first 6 months of life
- sudden BILIOUS vomitting
midgut volvulus
- modality
- findings
- upper GI/SBFT
- corkscrew configuration of small bowel in setting of malrotated small bowel
Colonic diverticulosis
- what
- sx
- multiple diverticula within colon, usually in older pts or pts with constipation
- asymptomatic to pain, constipation, bloody stools
colonic diverticulosis
- modality
- findings
- NECT (non-enhanced CT), barium enema
- many small outpourings, often filled with air/contrast material
Diverticulitis
- describe
- sx
- complications dt inflammation of colonic diverticular dz
- abd pain, initially LLQ
Diverticulitis
- modality
- findings
- CECT (contrast enhanced)
- pericolonic stranding, bowel wall thickening
- generally on LEFT side
Infectious colitis
- describe
- sx
- inflammation of colon dt infection, inflammation, ischemia
- abd pain, diarrhea
Infectious colitis
- modality
- findings
- NECT/CECT
- long segment bowel wall thickening and enhancement (short segment would be more likely neoplasm)
Ischemic colitis
- describe
- sx
- inflammation fo colon secondary to vascular insufficiency/ischemia
- abd pain, blood stools, usually older pts with advanced atherosclerosis OR younger pts with coagulopathy
Ischemic colitis
- modality
- finding
- CECT (contrast bc want to see arteries too)
- Findings: inflammation fo colon, esp in watershed area (splenic flexure), thumb printing, submucosal edema (target sign)
Mesenteric/intestinal ischemia
describe
- vascular compromise of bowel
- often secondary to arterial or venous occlusion, bowel obstruction, hypotension
Mesenteric/intestinal ischemia
- sx
- modalitiy
- pain out of proportion to PE findings
- CECT w/wo NECT
Mesenteric/intestinal ischemia
- findings
Earlier/better to later/worse:
- pneumatosis intestinal (air in intestines)
- portal venous gas
- pneumoperitoneum
- submucosal hemorrhage/necrosis
Colon cancer
- describe
- sx
- most common ca of GI tract
- often insidious, altered bowel habits, anemia, obstruction, blood stools
Colon cancer
- modality
- findings
- Fluoro, CT, MRI
- polyps under fluoro, apple core lesions
- more often on RIGHT side
Appendicitis
- describe
- sx
- inflammation of appendix
- RLQ pain
Appendicitis
- modality
- findings
- US, CECT
- thickened and fluid filled. US shows surrounding hypervascularity
- complications: abscess and perforation
Hepatic steatosis
- what
- sx
- fatty infiltration of the liver
- usually asymptomatic
hepatic steatosis
- modality
- findings
- US, NECT, MRI
- diffuse hyper echoic appearance of liver with loss of detail of periportal fat
- darker appearance than spleen tissue, should be the same
Cholelithiasis
- what
- sx
- stones in biliary system
- asymptomatic, can have RUQ following meals
Cholelithiasis
- modality
- findins
- US (or NECT)
- shadowing lesions/stones on US
- CT shows calcified stones
Acute cholelithiasis
- what
- sx
- inflammation of gallbladder, usually secondary to gallstones
- RUQ pain (biliary colic)
Acute cholelithiasis
- modality
- findings
- US (CECT, HIDA)
- thickened gallbag wall, pericholecystic fluid, gallstones
- HIDA shows non-visualization of gallbladder
Omental infarct
- what
- sx
- vascular compromise of greater omentum
- pain, RLQ tenderness (can mimic appendicitis)
Omental infarct
- modality
- findings
- NECT
- focal area fat stranding, sometimes with halo or swirling appearance
- on RIGHT side
Epiploic appendagitis
- what
- sx
- non-specific inflammation of colonic epiploid appendage
- pain, usually left
Epiploic appendagitis
- modality
- findings
- CT
- fat density structure with surrounding inflammation, the adjacent bowel is spared/unaffected (unlike diverticulitis!)
What are the three common findings on the LEFT side only
- epiploic appendagitis
- diverticulosis
- diverticulitis
Pancreatitis
- what
- sx
- inflammation fo pancreas, usually from ETOH, gallstones, idiopathic
- epigastric pain radiating to back
Pancreatitis
- modality
- two types of findings
- CECT
- two forms: edematous and necrotizing
Edematous pancreatitis findings
homogenous tissue
Complications of pancreatitis
- surrounding fluid collections
- pseudoaneurysm
- portal/ splenic vein thrombosis
- duodenitis
Ascites
- what
- sx
- fluid in peritoneal cavity
- abdominal distention
Ascites
- modality
- findigns
- US, NECT/CECT
- fluid, thickening of peritoneum lining (peritonitis)
Cecal volvulus
- what
- sx
- torsion of cecum around mesentery, leads to obstruction
- obstruction: vomiting, pain, distention
Cecal volvulus
- modality
- findings
- plain film, fluoro, CT
- distended loop of large bowel with axis from RLQ to LUQ
- haustra preserved
- often requires sx
Sigmoid volvulus
- what
- sx
- twisting of sigmoid colon on sigmoid mesocolon
- large bowel obstruction, bloating (no vomiting)
Sigmoid volvulus
- modality
- findings
- plain film, CT
- loss of haustra (smooth), coffee bean sign with axis towards LLQ
- tx with rectal tube insertion for decompression
Small bowel obstruction
- what
- sx
- most common cause is adhesion from sx (get good hx)
- crampy abd pain, n/v
Small bowel obstruction
- modality
- findings
- plain film, CT
- dilated loops, air fluid levels, gasless abdomen. CT can show transition points
Free air
- what
- sx
- air outside bowel, free in abd cavity
- usually from iatrogenic causes (prev sx or perf from ERCP), infection, trauma
- sx: pain
Free air
- modality
- findings
- plain film, NECT
- upright radiograph show air under diaphragm
- left lateral decub shows air between liver and wall
- CT shows air outside bowel lumen
*investigate cause of free air!!
