Dr. Fung OHSU Body Radiology. Patient Preparation Education Approximate duration of the exam Breath-holding Stress importance Expiration If cannot sustain.

Liver MRIDr. Fung

OHSU Body Radiology

Patient Preparation• Education• Approximate duration of the exam• Breath-holding• Stress importance • Expiration• If cannot sustain BH, slowly inhale over time• Practice with patient

• Describe sensations of Gd infusion

• 2L NC O2

• No O2 if patient has COPD/emphysema: ASK!

•Patient Position• Supine• Feet first• Cushion under knees to relieve back pressure• Arms at sides

• Coil Position• 3 fingers below xyphoid

process• Ensure parallel

positioning• Other• Ear plugs• Emergency button• Anxiolytic• Music

3-Plane Localizer• Ensure coil is placed properly for optimized liver imaging.• Run calibration (reference) sequence for ASSET/SENSE.•2 with BH Exp, 2 Free Breath• If patient moves or coil position is changed, rerun calibration scan.

• Clinical• Quick eval of spine

Ax/Cor Single Shot TSE• Coronal SSFSE/SSTSE T2

• FOV <48 cm• SLT/gap: 8 mm/0• ASSET/SENSE: none • BH (Arms Up if Possible)

• Axial SSFSE/SSTSE T2• FOV <34 cm• SLT/gap: 8 mm/0• ASSET/SENSE: none• BH• Liver through kidneys• Two acquisitions if necessary

• Overlap acquisitions• NO INTERLEAVE

•Clinical • Overview of anatomy• Fluid-filled structures• Liver size

Coronal 3D FIESTA/B-TFE• Parameters

• FOV: 38 cm• SLT/gap: 3-4

mm/reconstructed to 1-2 mm• ASSET/SENSE: min• BH• Liver through pancreas• Arms Up if possible- Fold over

• Clinical• Poor man’s MRCP• Decreases dephasing in

patients with significant ascites

Axial 2D FIESTA/B-FFE• Parameters

• FOV: <34 cm• SLT/gap: 5 mm• ASSET/SENSE: min• BH: (resp-trig uncooperative

patient)• Liver through bottom of

kidneys

• Clinical• Vascular patency: important if

unable to adequately BH during post-Gd sequences

Axial Dual Echo SPGR (In/Out Phase)• Parameters

• FOV: <34 cm• SLT/gap: 7 mm/1 • ASSET/SENSE: none• BH• Two acquisitions if necessary

• Overlap acquisitions• NO INTERLEAVE

• Repeat as necessary to optimize image quality

• Run 3D Dixon on MR1 for In/Out Phase imaging

• Clinical• Detect lipid and iron• Evaluate kidneys• T1 appearance of lesions

Axial Resp-Trig FSE T2 Fat Sat• Parameters

• FOV: <34 cm• SLT/gap: 7 mm/1• ASSET/SENSE: None• Respiratory Triggered• Liver through bottom of

kidneys• Position gating trigger on

dome of diaphragm half in lung field/half in liver

• Clinical• Increased lesion conspicuity• T2 characteristics• Lymphadenopathy

Axial 3D LAVA/THRIVE/DIXON• Parameters

• FOV <34 cm• SLT/gap: 4-5 mm/reconstructed to 2 mm• ASSET/SENSE: 1.5, max• BH• Liver through bottom of kidneys

• Breath-holding• Expiration• Practice breathing with patient• Watch respiratory graph so breathing

cycle not interrupted• Stress importance of these images• If can’t hold breath long enough, slowly

and steadily inhale (as had practiced before the exam)

• Precontrast• Ensure :

• Adequate coverage• Adequate fat suppression• Patient understands BH• No artifacts through liver

Axial 3D Dynamic Timing• Post-Contrast

• Arterial: 25s after start of injection – MOST INPORTANT SCAN• prior to scanning this sequence, please remind patient of the importance

of this sequence• Arterial Phase is for Hepatic Artery uptake, NOT early arterial (30sec k0

time)• This time depends on k0 time, injection rate, cardiac output,

hemodynamics• We may be switching back to bolus tracking because of these variables.

• Portal: 60s after start of injection• Late Portal: 100s after start of injection• Equilibrium: 180s after start of injection• 10-min Delay (FSPGR)• Please send images to PACS in proper fashion (Philips)!

• Clinical• Lesion detection and characterization

Axial 3D DIXON (Water Images)• Parameters

• FOV <34 cm• SLT/gap: 4-5 mm/reconstructed to 2 mm• BH• Liver through bottom of kidneys

• Breath-holding• Faster scan and better fat sat than THRIVE• ONLY available on MR1 Philips• 3D Dixon will also replace In/Out Phase on MR-1

• Ensure :• Adequate coverage• Adequate fat suppression• Patient understands BH• No artifacts through liver

10min Delay Axial FSPGR Fat Sat• Parameters

• FOV <34 cm• SLT/gap: 7 mm/1• ASSET/SENSE: None• BH• Liver through Aortic

Bifurcation• Two acquisitions if necessary

• Overlap acquisitions• NO INTERLEAVE

• Repeat as necessary to optimize image quality

• Clinical• Evaluate for delayed contrast

enhancement

Additional Optional Sequences• DWI

• Parameters: as specified on the Philips Scanner• Through the liver• Please be sure to perform ADC map• Clinical: Lesion detection, esp. for metastatic

lesions to liver

• EOVIST Protocol• Axial Post-contrast LAVA/THRIVE at 5 min’s and 20

min’s• Axial and coronal Pre- and Post-contrast “STEALTH”

as required by the radiologist oncologists• Clinical: Lesion detection

MRCP To be performed after contrast sequencesDefault is MRCP + liver mass protocol

Rad will specify if study to be done without contrast

MRCP 3D AxialFOV: <34 cmSLT/gap: 1.4 mm/0ASSET/SENSE: minimumRespiratory TriggeredThrough bottom 2/3 of liver, including pancreas

MRCP Thin SliceParameters:

FOV: 32 cm SLT/gap: 4-5 mm/0 Slices: 15, each ASSET/SENSE: None BH

• Off Axial image, select image showing CBD through pancreatic head• Coronal • Image posterior to CBD as it passes through the pancreatic head to anterior to the

porta hepatis• Whole gallbladder should be included although can be sacrificed to image whole CBD

• RAO Coronal Oblique• Rotate 20-30⁰ counterclockwise Include CBD• Gallbladder not necessarily included

• LAO Coronal Oblique• Rotate 20-30⁰ clockwise from straight coronal• Center on CBD• Entire gallbladder included

RAOCoronal

LAO

MRCP Thick Slab, RadialParameters:

FOV: 32 cm SLT/gap: 40 mm/0 Slices: 12 ASSET/SENSE: None BH

• Off Axial image, select image showing Pancreatic Duct (Pancreatic Head)

• Multiple slabs off different angles (15-30⁰ intervals)• Adequate pause to eliminate crosstalk

RADIAL