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Liver MRI

Liver MRI. Dr. Fung OHSU Body Radiology. Patient Preparation. Coil Position 3 fingers below xyphoid process Ensure parallel positioning Other Ear plugs Emergency button Anxiolytic Music. Education Approximate duration of the exam Breath-holding Stress importance

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Liver MRI

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  1. Liver MRI Dr. Fung OHSU Body Radiology

  2. Patient Preparation • Coil Position • 3 fingers below xyphoid process • Ensure parallel positioning • Other • Ear plugs • Emergency button • Anxiolytic • Music 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. MRCP • To be performed aftercontrast sequences • Default is MRCP + liver mass protocol • Rad will specify if study to be done without contrast • MRCP 3D Axial • FOV: <34 cm • SLT/gap: 1.4 mm/0 • ASSET/SENSE: minimum • Respiratory Triggered • Through bottom 2/3 of liver, including pancreas

  15. MRCP Thin Slice • Parameters: • 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 portahepatis • 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 Coronal LAO RAO

  16. MRCP Thick Slab, Radial • Parameters: • 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

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