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Okay, we're gonna get started with

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neonatal head ultrasound.

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So the goal of this, uh, quick PowerPoint is

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to review why we image when to image.

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We're gonna review ultrasound scanning techniques,

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normal development in normal anatomy,

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and then we'll briefly review some normal

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and abnormal cases.

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So why do we do screening head ultrasound?

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Well, in premature infants,

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most hemorrhage occurs within one week of life.

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95%

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of intracranial hemorrhage in premature infants we

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see within one week of life.

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And that is why we image when we image, of course,

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you're always going to be asked for four cause imaging such

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as enlarging head circumference or decreased hemoglobin

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and hematocrit, and they're searching for the site of

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where the bleed is coming from.

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The head is a common location where there will be, um,

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incidental uh, hemorrhage as an etiology of decreased h

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and h on lab values.

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So timing is per the American Academy of Pediatrics.

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There's this review article of recommendations

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for newborn intracranial imaging,

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and you can see the timing of cranial ultrasound is, um,

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unless there's a reason to image earlier,

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is at one week of age.

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And then typically you will get a repeat scan at four

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to six weeks of age or at term

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or near the time of discharge, as long

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as there's no other abnormality.

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Um, the nicu, uh, will request additional imaging

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as needed if there are concerns on exam

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or abnormalities that we see on screening ultrasound.

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So at our institution, uh,

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we use a small footprint curved transducer as our workhorse

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for all, um, intracranial head ultrasounds.

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Um, if you don't have a nice small footprint, uh, mid array,

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uh, transducer, you can use a sector transducer,

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but you can see that the image quality is not quite as good.

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So we, we do both sagittal

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and coronal images, um, using the,

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we call it the baby head probe.

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Then we also will use a linear high frequency transducer

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to give us additional detail.

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So we basically do a head ultrasound twice for every infant.

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Um, the reason we can't use linear high frequency is

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that its transducer footprint is a good five centimeters in

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diameter, which is larger than almost all, uh,

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anterior fontanels and infants.

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The reason we can't do screening head ultrasounds is

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because of that soft spot that anterior fontanel gives us.

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A beautiful window into visualizing intracranial structure

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is, that's that structure that is circled in white

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occasionally for problem solving, we will image

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through the posterior fontanel

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that is the white arrow in this infant for every child,

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we definitely will look through the mastoid fontanel.

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So that's that blue circle there.

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Um, that gives us a great look at the

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posterior phospho structures.

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The, um, purple arrow was pointing to the frame and magnum.

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So if there's a question of lowline cerebellar tonsils

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or some abnormality of the upper cervical cord, um,

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we can use that frame

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And magnum view to get a good look at, uh,

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inferior posterior fossa

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and upper cervical canal structures.

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Um, this baby did have a palp level abnormality.

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That's why this BB is here.

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It was placed as as a marker of,

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of something they could feel on exam.

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But otherwise, a normal skull x-ray in this infant,

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I tell my residents all the time,

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just pretend you're looking at an MRI or a ct.

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When you're looking at a head ultrasound, don't freak out.

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It's just different shades of gray. Basically.

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Don't forget that although the anatomy is exactly the same,

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we are off plane compared to an MRI.

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So we are taking our transducer over the anterior fontella

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and angling to the left

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and the right to get our sagittal plane images.

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Whereas on an MRI, of course, the skull is not in our way

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of imaging and we can get true sagittal images.

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Same thing for the coronal plane.

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Um, again, we're just taking our transducer

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and angling it anterior to posterior to be able

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to get coronal plane images.

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Unlike an MRI where you get true Corona plane images.

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So when you're looking at something intracranial,

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some abnormality trying to place it, um,

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at the right spot in the brain for your report.

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Just remember you're a little bit off access for me.

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I think the anatomy looks awfully similar even

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though we are off plane.

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So whatever you would look at on an MRI,

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you wanna look at it the same way on an ultrasound.

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It, it's exactly the same anatomy.

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It's just, again, different shades of gray.

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So, um, depending on the age of your infant,

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you should be able to see all of these structures.

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So the cingulate sulcus is that big sulcus that kind

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of parallels the corpus clem, which is in blue.

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You can see your, uh, your midline structure super well.

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Your, uh, thalamus is that purple asterisk,

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your paral occipital sulcus.

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You can see that's that orange arrow.

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The fourth ventricle is the white asterisk, the ci magna.

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You can see super well, uh,

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through the anterior fontella as well.

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That is that yellow arrow.

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Don't forget, if you're looking at a dro venous sinus,

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make sure you put color on that structure.

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So in this example, it's the green arrow, your Sylvia

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and fissure is that sort of teal color.

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Third ventricle is that red color,

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and then the pons is that green asterisk.

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Of course, you can see the midbrain as well.

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My residents are often confused by this trans mastoid view,

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but it's super helpful

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for problem solving not only posterior fossa structures,

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but if there's something that you're seeing abnormal in the

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temporal lobes in that middle cranial fossa.

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The mastoid view is a great time

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to look at those structures.

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So don't forget to look at not only your dur venous sinuses,

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your uh, cerebellum, all

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of your posterior phospho structures,

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but look for the, um, dur venous sinuses as well.

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So not only do we get color images of our, uh,

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through our mastoid font.

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Now we'll get gray scale and color images.

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The anatomy is basically an axial view.

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It's a little bit off plane, um,

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but you can angle superiorly

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and inferiorly to cover more anatomy to be able

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to see more detail.