1/Kids now out of school? Headache already?? Usually neuroimaging doesn’t add much in headaches, but in occipital neuralgia MR neurography can add a lot.
2/ There are actually 3 occipital nerves:greater, lesser and least. They arise from the upper cervical nerves and innervate various areas of the dorsal scalp. The greater occipital nerve is the only one large enough to image and it arises from C2
3/The greater occipital nerve is the largest cutaneous nerve in the body and can be traced from its origin at the dorsal ramus of C2 along the scalp in MR neurography
4/Many pathologies can affect the greater occipital nerve, but most commonly, it is compression between muscles, resulting in occipital neuralgia. This is the basis behind Botox treatment for occipital neuralgia. Decompressive surgery can also be used to provide relief
5/Where is it compressed? Usually between the multifidus and semispinalis capitis. We can use MR neurography to rule out other pathologies of the nerve and confirm compressive injury
6/MR neurography can confirm unilateral dz preop or post op neuromas w/persistent pain. This is a pt w/unilateral right dz w/a brighter larger right nerve, indicating Sunderland 1 injury from compression
Not all headaches have to be a diagnostic headache with MR neurography 😉
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1/Do you get a Broca’s aphasia trying remember the location of Broca's area?
Does trying to remember inferior frontal gyrus anatomy leave you speechless?
Don't be at a loss for words when it comes to Broca's area
Here’s a 🧵to help you remember the anatomy of this key region!
2/Anatomy of the inferior frontal gyrus (IFG) is best seen on the sagittal images, where it looks like the McDonald’s arches.
So, to find this area on MR, I open the sagittal images & scroll until I see the arches. When it comes to this method of finding the IFG, i’m lovin it.
3/Inferior frontal gyrus also looks like a sideways 3, if you prefer. This 3 is helpful bc the inferior frontal gyrus has 3 parts—called pars
Brain MRI anatomy is best understood in terms of both form & function.
Here’s a short thread to help you to remember important functional brain anatomy--so you truly can clinically correlate!
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)
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.