1/As my attending once said, “If I’ve seen it once, I’ve seen it…well once.”
A 🧵about an interesting case that I’ve seen once in 15 years and never again. #medtwitter #radres #FOAMed #FOAMrad #neurorad #Meded #Neurosurgery #HNrad
2/Pt with history only of diabetes came in with altered mental status. There were these super bright round balls in their ventricles. It looked like a snowman massacre happened, with big round snowballs in the ventricles
3/On MRI, these had intrinsic T1 hyperintensity w/chemical shift artifact--they looked like boba tea pearls floating in the ventricles. Typically, we think of chemical shift w/fat--but these were not fat on the CT!! They did not enhance & otherwise, brain was unremarkable for age
4/The answer is looking you right in the eye! This is intraventricular extension of silicone from a silicone retinopexy. Silicone dissections along the optic sheath into subarachnoid space & ventricles. It is typically asymptomatic. And now you've seen as many of these as me!😉
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1/The 90s called & wants its carotid imaging back!
It’s been 30 years--why are you still just quoting NASCET?
Do you feel vulnerable when it comes to identifying plaque vulnerability?
Here’s a thread to help you identify high risk plaques with carotid plaque imaging
2/Everyone knows the NASCET criteria:
If the patient is symptomatic & the greatest stenosis from the plaque is >70% of the diameter of normal distal lumen, patient will likely benefit from carotid endarterectomy.
But that doesn’t mean the remaining patients are just fine!
3/Yes, carotid plaques resulting in high grade stenosis are high risk.
But assuming that stenosis is the only mechanism by which a carotid plaque is high risk is like assuming that the only way to kill someone is by strangulation.
1/I always say you can tell a bad read on a spine MR if it doesn’t talk about lateral recesses.
What will I think when I see your read? Do you rate lateral recess stenosis?
Here’s a thread on lateral recess anatomy & a grading system for lateral recess stenosis
2/First anatomy.
Thecal sac is like a highway, carrying the nerve roots down the lumbar spine.
Lateral recess is part of the lateral lumbar canal, which is essentially the exit for spinal nerve roots to get off the thecal sac highway & head out into the rest of the body
3/Exits have 3 main parts.
First is the deceleration lane, where the car slows down as it starts the process of exiting.
Then there is the off ramp itself, and this leads into the service road which takes the car to the roads that it needs to get to its destination
3/At its most basic, you can think of the PPF as a room with 4 doors opening to each of these regions: one posteriorly to the skullbase, one medially to the nasal cavity, one laterally to the infratemporal fossa, and one anteriorly to the orbit