Diagnostic Imaging III Final Exam Study Guide - 2006
Which of the following (organ or structure outline) can be visualized in the normal AP supine abdomen without obstruction of bowel gas or fecal material?
a. stomach NO (view by gas on upright)
b. small intestines NO (gas only if pathology)
c. colon NO (gas possible without pathology)
d. spleen YES
e. liver YES
f. gallbladder NO (except: stones, only 30% calcify, chol stones don't show)
g. kidney YES (if stones 80% calcify, uric acid stones don't show)
h. pancreas NO (except: calcifications with chronic pancreatitis/alcoholism)
i. psoas muscle YES
j. ureter NO
k. urinary bladder YES (different SG of urine makes it show, if calculi 90% have Ca++)
l. ovary NO
m. uterus NO (except if calcified leiomyomas)
What is the most common abdominal mass?
SADPUCKER helps us remember all the retroperotineal organs. Name them?
aorta & ivc
colon (ascending & descending)
What are some common abdominal locations for calcifications to form?
lymph nodes esp dt TB
cancer incl adenoma of bowel
When might the urinary bladder appear pear shaped in a male?
with prostatic cancer, due to lymphadenopathy
What's the treatment for a porcelain gallbladder and why?
take it out because 10-20% develop cancer
Where do phleboliths form?
in deep pelvic veins
Describe the location of gas & barium in the stomach in supine, prone and upright positions.
Seems obvious enough: air goes to top, barium coats and goes to bottom, in any position.
Why is it necessary to include an upright or decubitus view when abnormal accumulations of intestinal gas is visualized? to shift fluids to side or bottom and see size of container
Describe the appearance of gaseous distention of the small versus large intestine.
normal to see gas in ST & LI – mb a little in the SI (mb concern for obstruction if > 3cm)
know location by mucosal contour: SI has many small folds, looks like "stacked coins" or "coiled spring" deformity if distended with gas, "feathery" look of jejunum, LI will reveal haustra unless stretched to its very limit
What is a sentinel loop?
a dilated bowel segent dt local ileus as in IBD
Posterior displacement of the magenblasse is suggestive of enlargement of which organ?
What is the normal orientation and position of the kidneys?
visible dt the presence of perirenal fat
inferior pole is more lateral than superior
Left T11-L2, Right T12-L3
What is a phlebolith?
a venous calcification, or stone in vein
usu around edges of pelvis; if midline: worry, look for masses
dense, oval, well-defined; concentric or slightly eccentric interior lucency
Is plain film the best modality for diagnosis of an abdominal aortic aneurysm? If not, what is/are the best choice(s)?
NO, Ultrasound is best
50-80% show calcification on x-ray
Where are the normal constrictions of the esophagus?
left mainstem bronchus
What can cause the esophageal muscosa to thicken--besides GERD?
cirrhosis of the liver
Name the ligament that suspends the duodenal-jejunal junction to the upper lumbar spine.
ligament of treitz
Mucosal folds are called rugae in the stomach. What are they in the small intestine?
in colon the haustra are sacculations and plicae semilunaris are circumferential
What are the longitudinal bands along the colon?
What's a normaml diameter for the ileum?
What's the average length of the appendix?
What hangs in front of the transverse colon on the front of the abdomen?
the greater omentum
What is the only organ that lies in front of the stomach?
Describe the appearance and location of pancreatic calcification. Give the most common cause.
Numerous dense, discrete opacities that cross the midline (spine & aorta) at L1-2
mc cause: chronic pancreatitis
What is the maximum diameter of a healthy aorta in the abdomen?
usually progressively enlarge
rare to rupture under 6cm
5% mortality rate for elective surgery
90% mortality from rupture
US diagnostic, 98% accurate
Which 3 pt groups have highest incidence of aortic calcifications?
smokers, hypertensive pts, diabetic pts
usu below renal arteries
What is a dermoid cyst?
teratoma: a congenital tumor, primaroily ectodermal tissue, usu benign
MC ovarian tumor!!
skin like cyst containing ectodermal tissues: teeth, bone, hair
usually has fat pad visible on xray surrounding harder tissues
If you see a round calcified blob in the right lower quadrant, what's #1 on the DDX?
fecalith in appendix
Which abdominal artery is the most serpiginous in shape?
What tube found only in men may calcify low in the pelvis?
vas deferens, calcifies dt repeat infx
What infections are likely to cause calcifications of the vas deferens?
TB, gonorrhea, syphilis, or chronic UTI of any kind
usu bilateral and symmetric
most in diabetic pts
mb dt aging, degeneration
What abdominal arteries most commonly have aneurysms?
aorta (1:250 people over 50 die per year from AAA, 50% symptomatic at dx)
Describe the appearance and location of a calcified uterine fibroma.
Leiomyoma - MC tumor of the uterus
masses have lucencies within them and mb whirled in appearance
in uterine area
Describe the appearance and usual location of prostate calculi.
sharply defined homogenous concretions
may appear above or in pubic symphysis
(may result fr TB or chronic pancreatitis)
What is an injection granuloma?
granulation tissue when injections have been administered IM
usu in gluts, on AP view may overlap ilium
category: solid mass
Describe the appearance of residual contrast material in diverticulum.
chocolate chip sign: small pockets where contrast is trapped in each diverticulum
What is a staghorn calculus?
triple phosphate stone aka struvite (80% calcify) concretions
homogenously dense & sharply outlined
(pure uric acid stones are radiolucent)
struvite stones formed in alkaline conditions may occupy entire renal pelvis & calyces
If granulomas are found in both liver and spleen, what organism is implicated?
If granulomas are in liver only, what organism?
Briefly describe the four patterns of abdominal calcification and give examples.
Concretions: calcified mass formed in the lumen of a vessel or hollow viscus, looks solid but may have facets or circumferential laminations (gall stones, appendicoliths), Homogenous (urinary calculi), Examples: Phleboliths, prostatic concretions, gallstones, staghorn calculi, fecliths, LV granulomas, PN concretions.
Conduit Wall: calcification forms in the walls of hollow tubes; classically appear as parallel tracks of calcification (ATH plaques are not continuous); MC in the abdomen, aorta & its terminal branches. Examples: Aortic, common & Internal iliacs, splenic (serpentine appearance), renal (most dt atherosclerotic plaquing), vas deferens.
Cystic: any calcium depostion in the wall of an AbN fluid filled mass; epithelial-lined true cysts, pseudocyst, spherical & ovaoid aneurysms; Crucial finding for Cystic Patterns: smooth, curvilinear rin of opacity, rim need not be complete, rarely laminated. Examples: AAA, common iliac, splenic artery, pocelain GB, Splenic cyst, Mesenteric or omental cysts.
Mass: Irregular border; complex inner architecture (mottled, whirled, amorphous, patchy); Psammamatous = spread out like sand or cloud, ovarian CA seeding. Examples: MC is a LN!!!, bowel adenomas, hamartomas, TB or pyogenic abscess, leiomyoma, adrenal gland, calcification, nephrocalcinosis.
What is the percentage of radiolucent vs. radiopaque gallstones?
approximately 30% calcify (radiopaque)
70% we won't see on x-ray so order an US (70% radiolucent)
What is a porcelain gallbladder and its significance?
calcification of the GB wall-->risk: 10-20% develop carcinoma of the GB
What is a hiatal hernia how may it appear on plain films?
protrusion of a portion of the stomach upward through the diaphram
magenblasse above level of diaphragm
What is the difference in appearance in a contrast (barium) study of polyp, ulcer and diverticulum?
Polyp: intrinsic mass may be pendulous or flat, may narrow lumen
Ulcer: may be visible in profile, esp if in lesser curvature of stomach, mb seen anywhere in the ST or proximal duodenum but are mc in antrum, pyloric canal, & duodenal bulb
if the ulcer has perforated free air mb seen under the diaphram on an upright film
diverticulum: evidence of an extrinsic mass narrowing the lumen is the mc observation, occ a sinus tract fr the colon
to the pericolonic mass will be seen, rarely a fistula to the BL or uterus cb demonstrated. The usu site is the sigmoid
colon but cb anywhere in the colon
Which abdominal organs are retroperitoneal?
pancreas, duodenum, ascending and descending colon, kidneys & adrenals
What are the parts of a flank shadow?
What is apple core deformity?
looks like string sign from ileocecal area but is a constriction of large bowel
usudt a concentric constriction of colorectal cancer in the ascending or transverse colon
the string sign that you can see is the core, the negative spaces may be in the shape of the top and bottom of an eaten-out apple, these are the ends of the normal bowel on either side of the constriction
What is the coffee bean sign?
when the colon is so distended with gas that the bean shape blob occupies the entire gut
What disease is most likely to cause a calcified abscess in the psoas?
What do you call the star-like shape of some gallstones on x-ray?
jack straw shape
can also look larger and almost cystic
and can have mercedes benz sign inside the stone
What is lead pipe appearance?
when a bowel segment is so distended that you can see no mucosal folding whatsoever
usu the colon without haustra dt UC
What are some causes of pneumoperitoneum?
bowel perforation, peptic ulcer, abdominal surgery, peritonitis, infection, trauma, air entering via female genital tract
Describe the appearance of the contrast within the collecting system of both kidneys during an IVP in a patient with obstruction from a kidney stone in one ureter.
stones lodge at jct with bladder,kidney, and where ureter crosses bone
kidneys will appear cloudy or "blushed" at first, later contrast accumulates in pelvis
later still it appears in ureters
When would a retrograde pyelogram be performed?
when you need to visualize the ureters but don't want to stress the kidneys
duplicate ureters, horseshoe kidney, obstruction, etc
What is the percentage of radiolucent vs. radiopaque kidney stones?
80-90% calcify (radiopaque)
What is hydronephrosis?
distension of the pelvis & calyces dt obstruction
obstrx mbdt tumor, a calculus, prostatic inflammation, or edema dt UTI