Can’t Miss Radiology

Big thanks to Dr Schiebler who came to conference to drop radiologic-knowledge bombs on us. This lecture was loaded with tons of information; here are some of the big take-aways!

Gimme a differential diagnosis for this CXR:

See the little white spots everywhere? That should make you think Miliary Tuberculosis (milliary like millet seeds) , histoplasmosis, or thyroid cancer.

This one was Miliary TB, how do you know? Look for other signs of hematogenously spread TB like: Pott’s disease, tubercular chorioretinitis, skin lesions, pulmonary cavitary nodules.** I’d google image all of these to get a better idea of the variety of presentations. 25% of the world has tuberculosis, it is spread by droplets and even as the spit dries the little guys can keep living. By these little guys I mean these:

See the source image
Acid Fast Stain: Tend to line up like sausages as above. Let’s go boards questions!

Changing course; here is the brain:

Linear areas of hyperintensity in the external and internal capsules with sparing of the lentiform nuclei. Obviously.

Refresher course, if I say this is a FLAIR MRI scan, you perk up and know that this means the CSF if dark (like a T1) but abnormalities are bright (like a T2.) This particular finding is called the “parenthesis sign.” See em? This is pathognomonic for Infectious Encephalitis. Now we don’t get a lot of infectious encephalitis around these here parts seeing as Chicago is cold enough that the wind feels like it wants to steal your kidneys BUT these are common elsewhere and may be increasingly more American as we warm up the globe with pollution. If you see parenthesis sign think possible Malaria, dengue, eastern equine, West Nile, etc.

Lastly, this image of the LAD is pertinent for calcifications.

f you don’t see the calcification… follow the arrow. If you don’t see the LAD, its where the calcifications are.

Calcifications may or may not be normal depending on age, sex and race. If you are an old white dude you have a 50% likelihood of having calcifications, go you! So use the MESA calculator to see if your patient should have calcifications in general or if this is an unexpected finding. To quote Dr. Schiebler, calcium deposits are “the single most important predictor of future cardiac deaths.” How? Well it can be a marker for a lipid plaque (not visible on CT.) Lipid plaques are way scarier than calcium because they can get mad and shoot off from the wall and clot the artery AT ANY TIME.  Women are way more likely to have lipid plaques than calcium so if you see calcium on a woman, especially one with a low MESA calculated score -then they are likely to have lipid plaques as well and should undergo further work up.

Again – Big thanks to our radiology friends who do this for us and big thanks again for helping us learn some image magic!

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