Interactive Transcript
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This is an MRI of the brain
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in a three-year old child with developmental delay.
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And there's a nice normal appearance
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of the lateral ventricles,
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appropriate myelination in both
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cerebral hemispheres.
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We're not seeing any issues yet until we get
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down a little bit lower on the right posterior
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aspect of the mesocephalon.
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We see this area of T1 shortening.
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We don't know for certain what this is yet,
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but there's a couple of things we can do.
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One of the things people will sometimes do to
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evaluate a finding is do post-contrast imaging.
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It's still bright on post-contrast imaging,
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but on post-contrast imaging,
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we don't know if this is bright signal from post
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contrast enhancement
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or if it's the intrinsic T1 shortening
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from this finding to begin with.
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However, prior to giving contrast,
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T1 fat-suppressed imaging was performed
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and the bright signal went away.
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That confirms that this is fat,
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and so therefore, it is a lipoma.
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And similarly, on post-contrast imaging,
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the post-contrast bright signal that we see here
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on this post-contrast T1-weighted imaging,
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goes away on post-contrast T1-weighted
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imaging with fat suppression.
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So, therefore,
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this finding has bright signal related to fat,
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which is a small lipoma of the tectal plate
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and is not an enhancing lesion.
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If it did not suppress on fat-suppressed imaging,
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then you have to wonder about other possible
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sources of intrinsic T1 shortening.
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One of the most common ones is subacute blood
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products or methemoglobin.
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In this patient,
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that small area of bright signal
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on T1 weighted imaging was originally raised
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as concern for a hematoma.
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But appropriate use of fat-suppressed imaging
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helped confirm that it was not a hematoma.
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A tectal plate lipoma will often show up at
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either the 5 o'clock or the 7 o'clock position,
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and that's exactly where we see
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it in this individual.
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So, being aware of the normal location
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for this lipoma,
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as well as being aware of the MRI techniques
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you can use to confirm the fatty nature,
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fat-suppressed imaging,
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both pre and post-contrast,
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in this case,
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it allows you to confidently state that this is
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an incidental lipoma that does not require
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follow-up and should have no implications
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to the brain development.
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