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!

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More from @teachplaygrub

Dec 5
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
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Let me help you out w/a thread about imaging in NPH! Image
2/First, you must understand the pathophysiology of “idiopathic” or iNPH.

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Nov 21
1/Time to go with the flow!

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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.

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C1 is in the lobby or neck.

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Nov 4
1/The 90s called & wants its carotid imaging back!

It’s been 30 years--are you still on NASCET?

Feeling vulnerable about plaque vulnerability?

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ajnr.org/content/46/10/…Image
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Oct 24
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So in AD look for a rapidly tapering Nike swoosh, w/hypometabolism in the parietal/temporal regions—sparing the anterior temporal pole Image
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Oct 17
1/My hardest thread yet! Are you up for the challenge?

How stroke perfusion imaging works!

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3/So if we can track how contrast gets to the tissue (by changes in CT density or MR signal), then we can approximate how BLOOD is getting to the tissue.

And how much blood is getting to the tissue is what perfusion imaging is all about. Image
Read 18 tweets

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