Liver and Biliary System MRI Scan
Live and Biliary MRI is used to diagnose and
study the following indications:
- Focal lesions and staging of neoplasm in the liver
- Benign hepatic disease, esp. hemangioma and focal nodular hyperplasia.
- Hemachromatosis and Gallbladder disease.
- Biliary ducts obstruction is also seen.
- Evaluation of liver infiltrants such as iron and fats.
Equipment use in Upper Abdomen MRI Scan
- Body coil volume torso array or multi-coil.
- RC bellows
- Ear plugs
- Pre gating leads if necessary.
Patient Positioning:
The patient position is supine on the examination couch
with the RC bellows is securely attached if needed. The longitudinal alignment
light is in the midline of the patient, and horizontal light passes to the
level of the 3rd lumbar vertebra, or the lower costal margin.
Suggested Protocol for liver and Biliary System MRI
Coranal Breath-hold technique T1 – Incoherent (spoiled)
This act as the localizer if three-plane localization is
unavailable, or as a diagnostic sequence. These slices are thick that relatively prescribed
from the vertical alignment light, from the posterior abdominal muscles to the
anterior abdominal wall, and horizontally from area of pubis symphysis to the
diaphragm is included in the image.
 |
| Coronal SE T1 weighted image through the abdomen demonstrating slice prescription boundaries and orientation for axial imaging of the liver. |
Axia GRE T1 +/- in and out phase
As for coronal T1, except prescribe slices from the
inferior margin of the liver to the diaphragm.
Delayed scan after contrast enhancement using chemical /
Spectral presaturation technique are sometimes necessary to evaluate arterial
and venous phases.
 |
| Axial FSE T1 weighted image through the liver. |
Axial SE T2 or GRE T2
Slice planning is just the same with the axial T1.
Axial SE or Breath-hold incoherent (spoiled) GRE T1 + Contrast Media
Slice planning as for Axial T1. |
| Axial fast GRE T2* through the liver with contrast. |
Additional Planning Liver MRI
MRCP – SS-FSE
MRCP is Magnetic Resonance Cholangiopancreatography it is a sequence which provides images in which only
fluids-filled spaces such as the gall bladder and biliary ducts return signal.
It is necessary to use very long TE’s and TRs to effectively nullify or
eliminate the signal from all tissues except those that having a long T2 decay
time. TEs in excess of 200 ms and TR of more than 10 s are required. If SS-FSE
is unavailable then an FSE sequence may be substituted.
 |
| Coronal SS-FSE image of the gallbladder (MRCP). Very long values of TR and TE were used to acquire images in which only fluid is seen. |
Diffusion Imaging
The use of real time imaging has application in the liver
and biliary system. This includes biopsies and thermal ablations of the lesions
under real time MR control. In addition, diffusion and perfusion techniques of
the liver have been developed that may negate the use of contrast agents in the
future. DWI images are overlaid onto T1 weighted acquisitions. The DWI image
set provides pathology information, whereas the T1 weighted acquisition
provides anatomical data. The images produced are not dissimilar to a PET / CT
scan. In addition, diffusion tensor imaging used in conjunction with parallel
imaging techniques enables differentiation of benign from malignant hepatic lesions
and may also assist in the quantification of hepatic fibrosis.
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