Lea Alhilali, MD Profile picture
May 7, 2022 12 tweets 5 min read Read on X
1/
My fellows complained they hate memorizing classifications, like LeFort. I thought, “There must be a better way—maybe understanding instead of memorizing.”

A #tweetorial about understanding the LeFort classification. #FOAMed #medtwitter #Medstudenttwitter @medtweetorials
2/
To understand LeFort, you need to understand facial buttresses.
These are not true anatomic structures but a way of understanding facial structure.
Facial bones support facial structures like a table supports food, with legs (vertical buttresses) and table top (horizontal)
3/
In the face, the two main structures the buttresses are supporting are the orbits and the alveolar ridges of the maxilla and mandible supporting the teeth
4/
The buttresses not only support against gravity, but also against the force of mastication, which sends force from the mandible all the way through the maxilla to the skullbase
5/
The buttresses are the table tops and table legs resisting these forces
6/
Horizontal buttresses—there is a tabletop underlying each of the structures that need support in the face: the orbit, maxillary teeth, mandibular teeth, and mandible
7/

Here is the illustration of the horizontal buttresses and their official anatomic names. However, the names aren’t as important as remembering where they are—and you can do that by remembering that each important structure has a tabletop right below it.
8/
Vertical buttresses—these are the support posts. And they are arranged just how you would arrange them if you were building a house. Two in front, two in back.
9/
Here is the illustration of the vertical buttresses and their official anatomic names. But again, names aren’t important—function is!
10/

Vertical buttresses act as suspension wires for the maxilla, suspending it from the skullbase. They are what keep your face on!
11/

LeFort fx is when your face (maxilla) gets take off! To take it off, we have to cut the suspension wires--all three (posterior, medial, and lateral). The posterior buttress (pterygoid plate) is always cut. That is why pterygoid fx's are the signature of LeFort injuries
12/

Where we cut the other two buttresses determines which LeFort fx we get.

And now, you can just think of cutting the suspension wire to the maxilla, and never have to memorize the LeFort classification again!

• • •

Missing some Tweet in this thread? You can try to force a refresh
 

Keep Current with Lea Alhilali, MD

Lea Alhilali, MD Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @teachplaygrub

May 17
1/ I always say, "Anyone can see the bright spot on diffusion images—what sets you apart is if you can tell them why it’s there!”

If you don't why a stroke happened, you can't prevent the next one!

Can YOU tell a stroke’s etiology from an MRI?

Here’s a thread to show you how! Image
2/First a review of the vascular territories.

I think the vascular territories look a butterfly—w/the ACA as the head/body, PCA as the butt/tail, and MCA territories spreading out like a butterfly wings. Image
3/Of course, it’s more complicated than that.

Medially, there are also small vessel territories—the lenticulostriates & anterior choroidal.

I think they look like little legs, coming out from between the ACA body & PCA tail. Image
Read 25 tweets
May 14
1/Got the diagnosis when it comes to vessel stenosis?

Or is your knowledge narrow when it comes to vessel narrowing?

When it comes to vasospasm, do you know why it happens or what to look for?

Here is the thread you NEED to unravel why vessels twist up! Image
2/Vasospasm results from subarachnoid hemorrhage (SAH) & a buildup of multiple factors

It’s like how you can handle 1 nag from your boss on Monday—but after nagging all week, you break down on Friday!

Same w/vasospasm—it doesn’t happen until the end of the week after SAH! Image
3/So what is nagging that causes the vessel to shut down?

When the body breaks down blood from SAH, it releases free heme

And this free heme causes a cascade of negative consequences, call heme-related inflammation

So free heme is the annoying boss! Image
Read 21 tweets
May 13
1/ “Now listen carefully!”

Everyone has so much fear about the anatomy where they hear!

Do you dread temporal bone anatomy?

Do find the understanding ossicles impossible?

Do you know the ice cream cone sign on CT & then nada?

Then you need this thread on ossicular anatomy! Image
2/For the middle ear, I have a rule of 3s.

Middle ear is divided into 3 parts & it contains 3 ossicles.

Today we will focus on the ossicles—each of which has 3 parts! Image
3/First ossicle you meet when you enter the middle ear is the malleus.

It’s called the malleus because it acts like a mallet that hits a drum—literally—the ear drum!

I think it looks like Dr. Evil’s mini me, with its short body and round bald head Image
Read 19 tweets
May 8
1/Asking “How old are you?” can be dicey—both in real life & on MRI!

Do you know how to tell the age of blood on MRI?

Here’s a thread on how to date blood on MRI!

After reading this, when you see a hemorrhage, your guess on its age will always be in the right vein! Image
2/If you ask someone how to date blood on MRI, they’ll spit out a crazy mnemonic about babies that tells you what signal blood should be on T1 & T2 imaging by age.

But mnemonics are crutch—they help you memorize, but not understand

If you understand, you don’t need to memorize Image
3/If you look at the mnemonic, you will notice one thing—the T1 signal is all you need to tell if blood is acute, subacute or chronic.

T2 signal will tell if it is early or late in each of those time periods—but that type of detail isn’t needed in real life

So let’s look at T1 Image
Read 21 tweets
May 3
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
3/ICA is divided into numbered segments based on landmarks that denote transitions on its way up the floors.

C1 is in the lobby or neck.

You can remember this b/c the number 1 looks elongated & straight like a neck. Image
Read 10 tweets
Apr 25
1/Have some confusion about tumor perfusion?

Do you go into a coma looking at scans for glioma?

Never fear!

Read on for this month's @theAJNR SCANtastic for what you need to know on the latest in brain tumor imaging!

ajnr.org/content/45/4/4…
Image
@TheAJNR 2/Since the prehistoric days of medicine (1979!), we knew that some brain tumor patients treated w/radiation (XRT) initially declined, but then get better.

Today, we see this on imaging, where it looks worse early, but then gets better.

Now we call this pseudoprogression. Image
@TheAJNR 3/Why does this happen?

XRT induces a lot of inflammatory changes—from initiating the complement cascade to opening the blood brain barrier (BBB)

It’s these inflammatory changes that make the imaging look worse. Image
Read 21 tweets

Did Thread Reader help you today?

Support us! We are indie developers!


This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us!

:(