2/Let’s start at the top. At the vertex is the superior frontal gyrus. This is easy to remember, bc it’s at the top—and being at the top is superior. It’s like the superior king at the top of the vertex.
3/It is also easy to recognize on imaging. It looks like a big thumb pointing straight up out of the brain. I always look for that thumbs up when I am looking for the superior frontal gyrus (SFG)
4/The SFG contains the supplementary motor area or SMA. As the name suggests, SMA contains a motor region—but not as expected, it also contains a verbal area. I remember that the motor portion is behind the language area bc we all walk before we talk, so motor comes before verbal
5/Next to the superior frontal gyrus is the middle frontal gyrus. It is important for verbal memory. I think it looks like the knuckles of a hand
6/So every time I read a brain MRI, I look at the vertex for the hand giving me the thumbs up. The thumb is the superior frontal gyrus, and next to it, the curved knuckles of the middle frontal gyrus
7/The superior frontal gyrus crashes into the motor strip or pre central gyrus. This is how I like to find the motor cortex. I follow the thumb back until it crashes into a gyrus—and I know that gyrus is the motor strip
8/The motor area of the superior frontal gyrus is right next to the motor cortex. I remember this bc when two cars crash head on, it’s their motors that crash into each other—so the motor area of the SMA crashes into the main motor strip.
9/You can confirm the motor strip by looking for the hand motor region. This is uniquely shaped like an Omega. You can remember that the hand motor region is shaped like an Omega bc Omega is a fancy watch brand and you wear watches near your hand
10/Motor strip goes into to the paracentral lobule, which connects the motor strip & main sensory strip. I think it looks like the “C” on Coach brand purses. I remember this bc this is eloquent cortex, some might say elegant—& elegant people own fancy brands like Coach & Omega
11/Finally, the cortex behind the sensory strip is the superior parietal lobule. It is the butt of the functional regions at the vertex. It is important for spatial orientation and hand function—so it makes sense that it sits right behind the hand motor and sensory cortices
12/So on every brain MRI I read, I go to the vertex & look for:
1. A thumbs up
2. Luxury brands around the eloquent cortex
3. The functional cortex backside (superior parietal lobule)
Hopefully, you will now be eloquent when it comes to functional brain anatomy! 😜
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2/Lumbar stenosis has always been controversial. In 2012, they tried to survey spine experts to come to a consensus as to what are the most important criteria for canal & foraminal stenosis. And the consensus was…that there was no consensus. So what should you use to call it?
3/Well, you don’t want just gestalt it—that is a recipe for inconsistency & disagreement. But you don’t want to measure everything either—measurements are not only cumbersome, they introduce reader variability & absolute measurements don’t mean the same thing in every patient.
2/ASPECTS stands for “Alberta Stroke Program Early CT Score.” It is meant to replace gestalt-ing what percent of the MCA territory is infarcted. Instead, it uses a 10-pt score to semi-quantitate the amount of infarcted tissue in the MCA territory on non-contrast head CT
3/You can think of it as a scorecard for the MCA.
For each region of MCA territory NOT infarcted, the pt gets one point
So the highest score possible is 10, and lowest score possible is 0
2/The PPF is a crossroads between the skullbase & the extracranial head and neck. There are 4 main regions that meet here. The skullbase itself posteriorly, the nasal cavity medially, the infratemporal fossa laterally, and the orbit anteriorly.
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
2/Calvarium & sinuses act as important protectors of your intracranial contents, most importantly, your brain. They are like a built in helmet to protect you from linebackers of life
3/The sinuses are actually even better than a helmet. They are like the crumple zone of a car, but for your brain. They can be crushed inwards, absorbing energy and keeping it from impacting your brain
2/When it comes to brachial plexus injuries, the most important distinction to make is whether it is a pre or post ganglionic injury. Pre ganglionic injuries are nerve root avulsions from the spinal cord and cannot be repaired, while most post ganglionic injuries can be repaired
3/It’s like repairing a house. If there’s a structural flaw at the beginning, before you’ve even built it, you won’t even try to build it, you’ll just scrap the design (preganglionic). But if there’s damage after the house is built, you can salvage it w/repair (postganglionic)
2/Brachial plexus is how the cervical nerves reach the arm. In the coronal plane, it looks like a slide, guiding nerves downward. Bc nerves are traveling laterally, sagittal MRI plane is our plane of choice to cut the nerves in cross section & see down the barrel of the nerves
3/But it’s more than a slide, it’s a complex highway, w/nerves joining & dividing—like highway off ramps & on ramps. If you want to know more about this intrinsic anatomy, see my first brachial plexus tweetorial here: