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So this is an example of an MR of a

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right glossotonsillar sulcus carcinoma.

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And just to get ourselves level set, this is

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an axial non-contrast T1-weighted image.

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This is a T1-weighted image with contrast.

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This one is plus contrast,

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but it's also fat suppression.

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And this is a T2-weighted sequence.

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So this was a patient that has a

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right-sided glossotonsillar sulcus carcinoma.

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Now, the way to analyze this

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is that typically, the way we're taught to look at things

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is we're taught to look at the soft tissues, but to

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really understand the glossotonsillar sulcus, what you

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have to do is really look at the airway right here.

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So here's a normal airway, and in

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general, things tend to be symmetric.

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So the area of the glossotonsillar

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sulcus here is on the left-hand side.

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Notice on the right-hand side, we can see

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the glossotonsillar sulcus here is pinched off,

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and there's actually an ulceration that runs

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deeply in the right glossotonsillar sulcus.

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So again, the definition of the glossotonsillar

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sulcus is that sulcus that's located between

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the tongue base, which is located here, and the

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lower pole of the tonsil, which is located here.

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So once we understand the normal anatomy,

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we can see that there is a tumor right here

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that's extending deeply, and it's continuous with that

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airway, and that continuation is actually an ulceration.

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Just to go over that in normal anatomy, this muscle

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runs from the genial tubercle back to the tongue base.

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That's the genioglossus muscle.

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These transverse fibers here, again, are

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the tongue base, so hence the term genio-

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glossus muscle. Anatomy is so important.

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This is the mylohyoid muscle.

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This is the hyoglossus muscle, and this

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gland right here is the sublingual gland.

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So on the contrast-enhanced T1-weighted with

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fat suppression, here's our glossotonsillar sulcus

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carcinoma extending deeply. On T2, we can see it's

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high signal here, which is the typical appearance

1:53

for neoplasms, malignant neoplasms.

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They do have a non-specific appearance to

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it, but again, this is a classic example

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of a glossotonsillar sulcus carcinoma.

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Now, a couple of clinical nuances in this

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case. When the referring physician looked at

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it, he thought it was a very, very subtle,

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small lesion. And when he looked at my report,

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he thought, oh my gosh, we used a lot of terms,

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like deeply aggressive ulceration, et cetera.

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They were unaware of this deep extent involving

2:20

the tongue base, and this is the real value.

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Not only of the anatomy, but understanding

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and explaining the full depth of extension.

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Because in this particular case, they thought

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they would be able to do a local oral robotic

2:33

surgery, but because of this, this patient was

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treated with non-surgical organ preservation.

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So in this particular case, the imaging made

2:41

a big difference and pivoted the patient

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from a surgical resection to being treated

2:45

with non-surgical organ preservation therapy.