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This was a patient who on intraoral examination, had

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a mass that was associated with the hard palate.

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As you recall,

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the hard palate has the highest concentration

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of minor salivary gland tissue.

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Now, the hard palate also has superficial

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squamous epithelium.

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So when one has a mass of the hard palate,

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there's a differential diagnosis.

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One of it could be a torus palatinus,

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which is just a calcified bony mass

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with overlying normal mucosa.

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We could have a squamous cell carcinoma,

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which is the most common malignancy

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of the hard palate.

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Or we could be dealing with a lesion that is of

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minor salivary gland origin of those tumors

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that are in the minor salivary glands.

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You may recall my little diagram,

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my little bar chart which said that 80% of minor

0:59

salivary gland neoplasms are malignant.

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You also recall I said that of minor salivary gland

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benign tumors the most common far and away is

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pleomorphic adenoma. Well, this person beat the odds.

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This is a pleomorphic adenoma of the hard palate.

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Let's demonstrate it.

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So we are looking at in this case on T1-weighted

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coronal and T2-weighted coronal images.

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Where is the hard palate?

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So the dark signal intensity

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here is the hard palate.

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And the tissue just below that dark signal intensity

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is going to be the overlying mucosa

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and eventually the soft palate.

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So let's demonstrate the abnormality.

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What we're seeing here is the bone of

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the hard palate. And more laterally,

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we lose the bone of the hard palate and we see an

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intermediate signal intensity mass which

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is outlined by my yellow marker.

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This is the normal signal intensity of the mucosa

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and minor salivary gland tissue of the right

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side of the hard and soft palate.

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So we've got a lesion here which is infiltrating

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from the midline and growing out like this.

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When we look at this lesion on the

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T2-weighted fat-sat scan,

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we see the normal overlying mucosa and actually

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a little bit of the musculature, if you will,

2:30

of the soft palate.

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But we also see this brighter area here,

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which is the area of the pathology.

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And it comes right along here.

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Now,

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one thing to point out is that the

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greater and lesser alveolar nerves will insert into

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the hard palate and extend to the

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teeth to innervate the teeth.

3:00

So these greater and lesser palatine foramina,

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incisive foramina,

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are branches of the second division of the fifth

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cranial nerve and therefore perineural spread can

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occur in malignancies of the hard and soft palate.

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And the reason why it came to mind is because

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this little junction right here,

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this little bony junction is usually where those

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greater and lesser palatine are going

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to come out into the palate.

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Let's look at this on post-gadolinium

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enhanced sequences. Here we go.

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And on the

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post-gadolinium enhanced sequences, you see some of the

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phenomena, which is that the normal mucosa and

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we'll see this on the nasal turbinates.

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The normal mucosa enhances pretty avidly here.

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Here's the normal mucosa of the

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overlying the hard palate.

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And in this case, we have a tumor that is not

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enhancing as much as the normal mucosa.

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So you can see that difference

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in signal intensity.

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So we sort of have reversed the grayscale here.

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Now,

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the tumor is darker than the normally

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enhancing mucosa of the hard palate.

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Because this is a lesion which is seen as very thin

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in the superior-inferior plane.

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It is harder to see that on the T1-weighted axial

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scans, where it would be somewhere in this area.

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So this turned out, as I said,

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the patient got lucky.

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This turned out to be a pleomorphic

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adenoma of the hard palate,

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a minor salivary gland benign

4:53

tumor in this individual.