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Now let's discuss some specific protocols for

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evaluation of pathology in pregnant patients.

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First, let's talk about

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evaluation of the appendix.

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Appendicitis is a common issue that pregnant

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patients deal with, and so it's important

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to know how these patients should be imaged.

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I'd like to point out that the typical

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appendicitis protocol in MRI should be

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the same for adult and pediatric patients.

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It's a non-contrast examination that uses

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multiplanar, single-shot T2-weighted images.

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The reason that we want to do single

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shot T2 is that it's a shorter exam, and

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so there is the decreased potential for

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degrading the images by motion artifact.

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We also obtain diffusion-weighted

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imaging of the abdomen and pelvis,

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and a coronal fat-saturated T2-weighted image.

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And so what we're trying to accomplish

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by obtaining these specific sequences

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is highlighting any inflammatory changes

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within and around an abnormal appendix.

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So on the T2-weighted images, we would see

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periappendiceal fluid and tissue edema.

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We may see diffusion restriction

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within an inflamed appendix.

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And so the way that you will find the appendix

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on MRI is you will look for the cecum.

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And you will next identify the ileocecal

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valve, which is here in this patient.

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Once you've found the ileocecal valve

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and terminal ileum, you will be within

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the neighborhood of the appendix.

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And so here it is for this patient

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as this linear tubular structure

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in the right lower quadrant.

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Next, let's talk about the protocol

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for general evaluation of the abdomen.

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This is very similar to a liver protocol

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MRI, which you may perform for hepatobiliary

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pathology or generalized abdominal pain.

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We'll first obtain multiplanar

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scout images, axial and coronal

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T2-weighted images of the abdomen.

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We'll perform in-phase and out-of-phase

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images to look for microscopic fat deposition,

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diffusion-weighted imaging with a corresponding

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ADC map, and a pre-contrast axial T1 of the abdomen.

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It's important to note that because we're

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imaging a pregnant patient, we won't

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perform the traditional post-contrast

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sequences which would then follow.

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And then if you're doing an MRCP for evaluation

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of the biliary tree, you can also add coronal

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single-shot T2-weighted imaging of the abdomen.

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Lastly, let's discuss protocols

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for imaging the placenta.

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Again, we'll perform a multiplanar localizer.

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And then we'll perform coronal,

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sagittal, and axial T2-weighted

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images of the abdomen and pelvis.

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You'll obtain both steady-state free

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precession and single-shot turbo spin

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echo images of the abdomen and pelvis.

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At most institutions, this

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is where the protocol stops.

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You can, however, add non-contrast T1-

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weighted images if the patient is having

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vaginal bleeding or if there's concern for

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placental abruption or retroplacental hematoma.

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Some institutions will also add

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diffusion-weighted imaging to act as a

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surrogate for blood flow and help further

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delineate the boundaries of the placenta.

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And then, as always, no intravenous

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contrast is used for this study.