Lea Alhilali, MD Profile picture
Neuroradiologist @HRInstitute_AZ. @BarrowNeuro. Striving to make learning neuroimaging and anatomy fun. If I can make you laugh, I can make you learn.
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Oct 10 21 tweets 8 min read
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 Image 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 Image
Oct 8 13 tweets 5 min read
1/Remembering spinal fracture classifications is back breaking work!

A thread to review the scoring system for thoracic & lumbar fractures—“TLICS” to the cool kids! Image 2/TLICS scores a fx on (1) morphology & (2) posterior ligamentous complex injury

Let's start w/morphology

TLICS scores severity like the steps to make & eat a pizza:

Mild compression (kneading), strong compression (rolling), rotation (tossing), & distraction (tearing in) Image
Oct 6 18 tweets 7 min read
1/Does PTERYGOPALATINE FOSSA anatomy feel as confusing as its spelling?

Does it seem to have as many openings as letters in its name?

Are you pterrified of the pterygopalatine fossa (PPF)?

Let this thread on PPF anatomy help you out. Image 2/The PPF is a crossroads between the skullbase & the extracranial head and neck

There are 4 main regions that meet here:

(1) Skullbase itself posteriorly, (2) nasal cavity medially, (3) infratemporal fossa laterally, and (4) orbit anteriorly. Image
Oct 3 8 tweets 3 min read
1/”Tell me where it hurts.”

How back pain radiates can tell a lot you about where the lesion is—if you know where to look!

Here’s how to remember lumbar radicular pain distributions! Image 2/Let’s start with L1. L1 radiates to the groin. I remember that b/c the number 1 is, well, um…phallic. So the phallic number 1 radiates to the groin. Image
Sep 19 17 tweets 6 min read
1/Ready for a throw down?

MMA fights get a lot of attention, but MMA (middle meningeal art) & dural blood supply doesn’t get the attention it deserves.

A thread on dural vascular anatomy! Image 2/Everyone knows about the blood supply to the brain.

Circle of Willis anatomy is king and loved by everyone, while the vascular anatomy of the blood supply to the dura is the poor, wicked step child of vascular anatomy that is often forgotten Image
Sep 15 13 tweets 5 min read
1/Time is brain!

So you don’t have time to struggle w/that stroke alert head CT.

Here’s a thread to help you with the CT findings in acute stroke! Image 2/CT in acute stroke has 2 main purposes

(1) exclude hemorrhage (a contraindication to thrombolysis)

(2) exclude other pathologies mimicking acute stroke. But you can also see other findings to help diagnosis a stroke. Image
Sep 12 18 tweets 7 min read
1/Do you feel there’s a back-log of findings in a spine MRI report?

Everyone talks about discs & facets, but not everyone talks about the endplates

Do you?

Do you need to talk about degenerative changes (Modic changes) of the endplates?

Here’s thread w/all you need to know! Image 2/Over 30 years ago, Modic et al. found there were 3 types of degenerative endplate changes:

(1) T2 bright changes (indicating edema, Modic 1)
(2) T1 bright changes (indicating fat, Modic 2)
(3) T1 & T2 dark changes (indicating sclerosis, Modic 3)

But what do they mean? Image
Sep 10 8 tweets 3 min read
1/Are you FISHING for a way to better evaluate subarachnoid hemorrhage?

Are you hungry for a way to classify these patients?

Donut you worry!

Here’s a short thread to help you remember the modified Fisher scale for classifying subarachnoid hemorrhage. Image 2/Just think of the brain as a donut. Like a donut, it’s a bunch of stuff around a hole in the middle.

Ventricles are the hole in the middle of the brain just like there’s a hole in the middle of the dough in a donut.

Just don’t quote me to your neuroanatomy professor…. Image
Sep 8 19 tweets 7 min read
1/Talk about twisting your back!

Do spine vascular lesions make your brain feel as tangled as the dilated vessels you see?

Want some more information on malformations?

Here’s a thread on spine vascular anatomy to give you durable knowledge on dural arteriovenous fistulas (dAVF)Image 2/To understand spinal dural AVFs, you need to understand basic spinal vascular anatomy.

The spine is LONG—to get blood from the top to the bottom is like going through the length of a marathon course Image
Sep 3 13 tweets 5 min read
1/Does the work up for dizziness make your head spin?

Wondering what to look for on an MR for dizziness

This month’s @theAJNR SCANtastic will tell you all you need about imaging Meniere’s disease!

ajnr.org/content/46/8/1…Image @TheAJNR 2/The etiology for dizziness can have very diverse causes—each with very different treatments.

So it is important to try to differentiate

Meniere’s is a common cause & we can help diagnose it w/imaging! Image
Aug 1 12 tweets 5 min read
1/They say form follows function!

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! Image 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. Image
Jul 29 9 tweets 4 min read
1/Talk about bad blood!

Do you know when a hematoma is going to expand?

Read on for month’s @theAJNR SCANtastic on all you need to know about imaging intracranial hemorrhage!

ajnr.org/content/46/7/1…Image @TheAJNR 2/Everyone knows about the spot sign for intracranial hemorrhage

It’s when arterial contrast is seen within a hematoma on CTA, indicating active
extravasation of contrast into the hematoma.

But what if you want to know before the CTA? Image
Jul 25 10 tweets 4 min read
1/Time to go with the flow!

Hoping no one notices you don’t know the anatomy of internal carotid (ICA)?

Do you say “carotid siphon” & hope no one asks for more detail?

Here’s a thread to help you siphon off some information about ICA anatomy! Image 2/ICA is like a staircase—winding up through important anatomic regions like a staircase winding up to each floor Lobby is the neck.

First floor is skullbase/carotid canal. Next it stops at the cavernous sinus, before finally reaching the rooftop balcony of the intradural space.Image
Jul 23 18 tweets 7 min read
1/My hardest thread yet! Are you up for the challenge?

How stroke perfusion imaging works!

Ever wonder why it’s Tmax & not Tmin?

Do you not question & let RAPID read the perfusion for you? Not anymore! Image 2/Perfusion imaging is based on one principle: When you inject CT or MR intravenous contrast, the contrast flows w/blood & so contrast can be a surrogate marker for blood.

This is key, b/c we can track contrast—it changes CT density or MR signal so we can see where it goes. Image
Jul 21 12 tweets 5 min read
1/Do you know all the aspects of, well, ASPECTS?

Many know the anterior circulation stroke scoring system—but posterior circulation (pc) ASPECTS is often left behind

25% of infarcts are posterior circulation

Do you know pc-ASPECTS?!

Here’s how to remember pc-ASPECTS! Image 2/Many know anterior circulation ASPECTS.

It uses a 10-point scoring system to semi-quantitation the amount of the MCA territory infarcted on non-contrast head CT

If you need a review: here’s my thread on ASPECTS: Image
Jul 2 18 tweets 7 min read
1/The medulla is anything but DULL!

Does seeing an infarct in the medulla cause your heart to skip a beat?

Does medullary anatomy send you into respiratory arrest?

Never fear, here is a thread on the major medullary syndromes! Image 2/The medulla is like a toll road.

Everything going down into the cord must pass through the medulla & everything from the cord going back up to the brain must too.

That’s a lot of tracts for a very small territory. Luckily you don’t need to know every tract Image
Jun 30 10 tweets 4 min read
1/Time is brain! But what time is it?

If you don’t know the time of stroke onset, are you able to deduce it from imaging?

Here’s a thread to help you date a stroke on MRI! Image 2/Strokes evolve, or grow old, the same way people evolve or grow old.

The appearance of stroke on imaging mirrors the life stages of a person—you just have to change days for a stroke into years for a person

So 15 day old stroke has features of a 15 year old person, etc. Image
Jun 27 20 tweets 8 min read
1/”I LOVE spinal cord syndromes!” is a phrase that has NEVER, EVER been said by anyone.

Do you become paralyzed when you see cord signal abnormality?

Never fear—here is a thread on all the incomplete spinal cord syndromes to get you moving again! Image 2/Spinal cord anatomy can be complex. On imaging, we can see the ant & post nerve roots. We can also see the gray & white matter. Hidden w/in the white matter, however, are numerous efferent & afferent tracts—enough to make your head spin. Image
Jun 23 13 tweets 5 min read
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! Image 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. Image
Jun 19 8 tweets 3 min read
1/Feeling intoxicated trying to remember all the findings in alcohol use disorder?!

Here’s something to put you in high spirits!

This month’s @Radiographics has the important neuroimaging findings alcohol use disorder!



@cookyscan1 @RadG_editor #RGphx pubs.rsna.org/doi/10.1148/rg…Image 2/There’s an easy rhyme to help you remember the important neuroimaging findings of alcohol use disorder

“Basal ganglia is white...”

Get intrinsic T1 shortening in the BG that makes it look white as a ghost! Image
Jun 9 11 tweets 5 min read
1/Need help reading spine imaging? I’ve got your back!

It’s as easy as ABC!

A thread about an easy mnemonic you can use on every single spine study you see to increase your speed & make sure you never miss a thing! Image 2/A is for alignment

Look for:
(1) Unstable injuries

(2) Malalignment that causes early degenerative change. Abnormal motion causes spinal elements to abnormally move against each other, like grinding teeth wears down teeth—this wears down the spine Image