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Here's a 52-year-old woman with right

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hip pain in which we combine analysis of

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sequences and pathology for labral assessment.

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We immediately have drilled down into

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the right hip with a small field of

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view with high-resolution imaging as

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opposed to bilateral scout imaging or

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bilateral imaging for overall symmetry.

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What's nice about this is the improved

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resolution and the fact that you don't

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have to go searching for a lot of other

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extraneous pathology outside of the hip,

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you're staying within the confines of the hip.

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We've got three similar but different sequences.

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On the far left is a PD SPIR.

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It is the detection sequence.

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It is also the sequence that

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does everything pretty well.

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It does labrum well.

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It does bone extremely well.

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It does soft tissues well.

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In fact, here's a soft tissue mass.

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And it does intra-articular well.

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In the center is an additive gradient echo

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sequence known as ADGE, MFFE, MEDIC, and MERGE.

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All of these terms coming

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from different vendors.

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It has very robust signal-to-noise

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properties, which allows for a small field

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of view, 3D thin section imaging with one

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or one-and-a-half millimeter sequences,

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and it does cartilage very, very well.

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It does not do bone marrow well at all.

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It's an articular emphasis, high-

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resolution sequence combined with 3D.

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On the right is another type of gradient

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echo, a non-additive simple gradient echo.

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This one, called balanced sarge, but it

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too has fairly robust signal to noise,

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is combined with 3D and is another very

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good to excellent cartilage sequence.

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This one has been combined with 3D.

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It is an excellent sequence when it is

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done along the long axis of the femur,

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the head, the neck, and the trochanteric

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region to assess labral pathology.

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In fact, it is a cardinal

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sequence for labral assessment.

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So three water-weighted images, a standard

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gradient echo with 3D and fat suppression,

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an additive gradient echo in the center with

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very robust signal to noise, both very good.

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fibrocartilage and hyaline cartilage sequences,

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and on the far left, the overall detection

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sequence to assess the presence of inflammation,

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water, and water-containing masses.

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Now let's talk about water for a minute.

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When water is pure, when water is unbound,

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it'll be very smooth and very bright on

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virtually every water-weighted pulsing sequence.

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When water is bound, it'll, it may

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not be as smooth and as bright,

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but it'll still be hyperintense.

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So this is an effusion in the inferior recess.

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On the other hand, there's swelling and

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irregularity along the supralateral capsule,

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lifting, stripping away the iliofemoral

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ligament from the underlying bone.

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But the most obvious sign is this:

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A soft tissue mass exhibiting

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water signal intensity that is

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consistent with a paralabral cyst.

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From a labral tear.

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How do we know?

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Because we're going to show you

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the labral tear in a moment.

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But here is a cardinal rule:

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Anytime you see a cyst or a pseudocyst,

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which this really is — a pseudocyst being

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water surrounded by fibrous tissue, not

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epithelium, around a ball and socket joint,

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it's almost always indicative of an underlying

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labral tear, even if you don't see it.

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How'd it get there?

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Diffusion or tracking of

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synovial fluid through the defect.

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These hip pseudocysts can be under the ligament,

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intra-articular cysts in the labrum, intralabral

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cysts, or through the ligament, as this one is.

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Let's scroll this image and see

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what else comes to the fore.

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Some signal intensity within the bone marrow,

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indicative of a penetrating class IV erosion

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secondary to advanced chondromalacia.

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We've already discussed that

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there is a capsular effusion.

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In the middle, we focus a little more

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heavily on the hyaline cartilage,

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which is diffusely thinned.

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The normal thickness being

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about three millimeters.

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There's also a little swelling

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of the ligamentum teres.

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Let's locate our labrum.

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Here it is.

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It should be tightly attached as a triangular

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structure to the supralateral acetabulum.

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It's not.

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It's floating freely.

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There's labral tissue that is detached

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and turned into a round, what I call,

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mushy, ill-defined, edematous structure.

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And there is your stripped capsule.

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This additive gradient echo,

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which does a great job for hyaline

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cartilage, also does a very good job

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for fibrocartilage.

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Let's scroll it.

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Anteriorly, still irregular, ill-defined

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signal intensity where normally a

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triangulated hypo intense structure should be.

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And then anteriorly we see more

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larger penetrating erosions into

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the anterior acetabular roof.

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Let's go back a bit.

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A through-and-through line between the

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triangulated labrum and the acetabulum.

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Yep, that's a tear.

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That's one way the fluid got

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there to create this cyst.

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Let's keep going back.

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Now the labrum looks a bit more normal.

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It's hypertrophied, but the triangle

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is attached to the acetabulum.

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And more, not unexpected, penetrating erosions.

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Now let's move over to the right side,

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where we have an axial oblique running

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along the long axis of the femur,

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head, neck, and trochanteric region.

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This is a standard label sequence.

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Let's start up high.

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We go all the way up to the top,

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and we see an erosion, a cystic

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erosion in the underlying bone.

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There it is right there in the roof, the

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anterosuperior roof of the acetabulum.

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There is our paralabral

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pseudocyst from our labral tear.

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Remember that the labrum is

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running over the top of the femur.

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So what you're seeing here is a linear area of

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hypointensity represents labrocapsular tissue.

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Now let's work our way down.

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As we move down, we see the labrum as a slit.

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A tear and the acetabulum.

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This tissue represents a portion of the ligament

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and capsule, and then more of the ligament.

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So these are recesses.

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A recess, a recess, labrum, tear.

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Let's track it.

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Labrum, tear, acetabulum,

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recess, capsule, ligament.

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Let's keep tracking.

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A well-defined small degenerated

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triangle, tear, acetabulum, capsule.

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Now I won't repeat it; I'll just have

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you look as I scroll my way down.

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The tear is still there.

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The tear is starting to close down.

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It's starting to close down.

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It has closed down.

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Hopefully, that helps give you some

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eye candy so you can learn to recognize

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the different areas of linear hyper

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intensity that are seen in the brain.

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in the anterior hip in a complex case

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with a labral tear so as not to confuse

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them with pathology, and vice versa.

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Let's move on, shall we?