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

Dec 23
1/Does trying to figure out cochlear anatomy cause your head to spiral?

Hungry for some help?

Here’s a thread to help you untwist cochlear CT anatomy w/food analogies! Image
2/On axial temporal bone CT, you cannot see the whole cochlea at once. So let’s start at the bottom.

The first thing you come to is the basal turn of the cochlea (makes sense, basal=bottom). On axial images, it looks like a banana. I remember both Basal and Banana start w/B. Image
3/As you move up to the next slice, you start to see the upper turns of the cochlea coming in above the basal turn. They look like a stack of pancakes.

Pancakes are the heart of any breakfast, so they are at the heart or middle of the cochlea on imaging. Image
Read 9 tweets
Dec 19
1/Talk about dangerous liaisons!

Abnormal brain vascular connections like a dural arteriovenous fistula (dural AVF) can be dangerous!

This month’s @theAJNR SCANtastic thread is here to you some durable knowledge about dural AVFs!

ajnr.org/content/45/12/…Image
2/Dural sinuses sit inside dural leaflets.

Arteries that feed the dura also feed the walls of sinuses, like vasa vasorum.

Arteries in the walls of veins are a natural connection between the veins and arteries—but these connections are usually closed in normal pts. Image
3/Whether these connections are open depends on pressure.

Like a hose w/a hole in it, at normal pressures, abnormal connections are not open.

But if pressure is increased w/thrombosis or stenosis, the connections open, like high pressure water squirting out through a hole. Image
Read 18 tweets
Dec 6
1/Time to FESS up! Do you understand functional endoscopic sinus surgery (FESS)?

If you read sinus CTs, you better know what the surgeon is doing or you won’t know what you’re doing!

Here’s a thread to make sure you always make the important findings! Image
2/The first step is to insert the endoscope into the nasal cavity.

The first two structures encountered are the nasal septum and the inferior turbinate. Image
3/So on every sinus CT you read, the first question is whether there is enough room to insert the scope.

Will it go in smoothly or will it be a tight fit? Image
Read 19 tweets
Dec 2
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
3/But dural vascular anatomy & supply are important, especially now that MMA embolizations are commonly for chronic recurrent subdurals.

It also important for understanding dural arteriovenous fistulas as well. Image
Read 17 tweets
Nov 27
1/Controversy in radiology can get tense!

The Mt Fuji sign for tension pnemocephalus is under scrutiny. When should you call it?

A thread about imaging this important neurosurgery complication Image
2/First, let’s clarify about what the Mt Fuji sign actually is

Most are familiar with the fact that large collections of pneumocephalus can compress the frontal lobes—making them look like the slopes of a mountain

But this isn’t actually enough to call Mt Fuji. Image
3/You also need to see frontal lobe separation

This means subdural air tension > the CSF surface tension between the frontal lobes

Water has one of the highest liquid surface tensions—so means pressure is high

This little V is why it looks like Mt Fuji, not any mountain Image
Read 9 tweets
Nov 25
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
3/Medulla has 4 main vascular territories, spread out like a fan: anteromedial, anterolateral, lateral, and posterior.

You don’t need to remember their names, just the territory they cover—and I’ll show you how Image
Read 18 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!

:(