Transcript Things I wish I had known sooner in Radiology

Pearls for 1st year.
By Naveen Garg PGY3
Radiology Physics Board
• PGY-2Registration with
the ABRJuly 1st - September 30th
• $400 late fee
• http://www.theabr.org/DR_Dates.htm
Reading Week
There is no free reading week, you must submit research to get it.
Last deadline for abstract submissions is Oct 1. for ARRS, earlier
for other conferences.
Wikirad
Internet Journal Club
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Decision Support
Collect rules
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Projects
1. AMSA Radiology Interest Group or Radiology
Resident e-mail listserv.
2. Contrast Reactions and Creatinine Clearance
3. Vague statistics in radiology reports: rare,
unlikely, likely, probably, relate with more clear
numbers for how common? Once a day, once
a month, once a year, once a career…
4. Internet Journal Club
5. Radiology Decision Support
General Approach to Imaging
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Have a differential diagnosis before you look at any images
Look at one organ at a time.
Look at tissue of interest
Is this image limited or the wrong modality?
What would it look like on ct, us, mri, nucs
Compare with normals and internet pictures if confused.
Fractures
• Ask mechanism of injury and region of focal pain
• If it looks abnormal: its usually either a limited view, fracture, or both.
• Limited views (no rotation views) may be because fracture or injury
limits mobility.
• Look at bones individually.
• Lower threshold for getting ct of pelvis, midfoot, spine, face
Fluoro
• Ted’s cheat sheet, w&w protocols.
• When Single contrast?
– <12 years old
– Old >70, limited mobility
– Ruleout obstruction or known anatomic defect
• Why scout? Obstruction, poop, barium, stones, pregnancy, free
air.
• Bronch, Hystero, etc: get angled views
• Male vcug, get urethra views frontal and lateral
• Esophageal perforation: ct with esophocat contrast
• Bladder perforation: ct with 200cc contrast through foley.
CT
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Windows: named after tissue that is gray and has best contrast (some of it is brighter
and some darker than gray).
Inflammation: fat gets whiter with edema and hyperemia. Walls get thicker with
edema.
Abscess: air, central necrosis, peripheral enhancement, reactive lymph nodes.
Vascular organs are denser and enhance more.
Tumors are usually neo (hypervascular)
Hematoma: heterogenous (layering / hematocrit effect)
Fat anywhere, water in csf spaces or bladder, air and contrast in bowel are your
friend. If you don’t see them, you have a limited exam or pathology.
CT Head
• Ischemia windows: look at basal ganglia, insular ribbon (temporal
lobe), cortex
• Subdural window: look at quadrigeminal plate cistern, tentorium, csf
• Soft tissue: look at scalp, sinuses
• Bone: look at orbits, nose, zygoma, lytic lesions, fracture if scalp
swelling.
• Only subtle finding to really worry about is hemorrage.
Ischemia and Bone Windows
IV Contrast
• See http://www.svhrad.com/CallGuide/OnCall.htm
for article on contrast allergy.
• Contrast timing:
– PE, AAA, Dissection
PE: pulmonary artery must be whiter than aorta.
AAA: without contrast to see crescent sign.
Dissection: with contrast to see flap
• Abdomen: get 3.2mm cuts if no contrast IV or oral or
can’t see what’s going on.
Ultasound
• Whiter = hyperechoic,
Darker = hypoechoic
•Fat:
•Hemorrage
•Bone
•Air
•Cyst:
•Vessels:
•Veins:
hyperechoic
hyperechoic
white line with shadowing
white line with shadowing
hypo to anechoic
doppler
compressible
MRI
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http://www.radiology.residentmanual.com/index.php/MRI_protocols
Water and pathology: White on T2, dark on T1 and FLAIR
Fat: white on T1 and T2, dark on STIR and out of phase
Bone Marrow: normally fatty (white on t1), replaced with edema or
other pathology (dark on T1)
Axons: fatty
Gray matter infarct: opposite of csf on DWI and ADC.
Bone cortex, stones, and ligaments: dark on everything.
Contusion is white
Tumor: hypervascular (neovascularity): white with gadolinium
Liver, Kidney, adrenals, Pancreas: tumor patterns, just look up in
brant and helms or mri book.
Nuclear Medicine
• V/Q scan:
if not clearly normal or high prob, look for artifacts or matched
defects.
– pioped criteria
• Bone Scan: if new abnormal uptake
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spine get obliques (to localize)
Others get laterals
X-ray or ct to confirm probably benign fx, djd
Mri for cancer
Don’t bother asking anyone other than bader, mukai, bertrand, chen, gupta for help.