X

Download Peripheral Vascular MR Angiography PowerPoint Presentation


Login   OR  Register
X

Share page



  Preview

               
Home / Health & Wellness / Health & Wellness Presentations / Peripheral Vascular MR Angiography PowerPoint Presentation

Peripheral Vascular MR Angiography PowerPoint Presentation

onlinesearch By : onlinesearch

On : Mar 14, 2014

In : Health & Wellness

Embed :
655
views

0
downloads
Login / Signup - with account for


  • → Make favorite
  • → Flag as inappropriate
  • → Download Presentation
  • → Share Presentation
  • Slide 1 - Peripheral Vascular MR Angiography Indications Equipment Technique Image Analysis Example Cases Reporting - Billing
  • Slide 2 - Thank You Yi Wang, PhD Qian Dong, MD Richard Watts, PhD Jim Meaney, MD Priscilla Winchester, MD Vince Ho, MD Neil Khilnani, MD Tom Chenevert, PhD David Trost, MD Craig Kent, MD Bernie Redd, MD
  • Slide 3 - Indications: Intermittent Claudication Non-healing ulcer Post bypass graft Aneurysm Pre free-flap Pediatric
  • Slide 4 - Indications for MRA Difficult access Renal insufficiency Cr > 2.0 Allergy to iodinated contrast Patient refuses conventional angiography
  • Slide 5 - Advantages of MRA No nephrotoxicity Allergic reactions rare 3D Anatomy and Physiology High Accuracy Affordable (reimbursement = $1159)
  • Slide 6 - Advantages of Gadolinium No pulsatility artifact No slice misregistration No in-plane saturation High resolution (1.8 x 1.6 x 2.6 mm) Fast
  • Slide 7 - Equipment for Peripheral MRA Magnet: 1.5 Tesla  high SNR 0.5 Tesla  requires more Gd High performance gradients Coil: body and head coil Injector vs hand injection Foam and straps
  • Slide 8 - Table Positioning Pole PVC tubing 2 inch diameter 3-4 meters long holes at 36 or 40 cm spacings
  • Slide 9 - Table Positioning Blocks
  • Slide 10 - Technique: younger vs older 2D TOF: 1 hour 3D Gd MRA: 87 seconds Older patient Young Adult 2D TOF Tech (30 years old) 2D TOF Radiologist (41 years old)
  • Slide 11 - Technique Pediatric – Young Adult (fast flow) Head or extermity coil 2D time-of-flight Gd almost never necessary Gating +/- Older Patients (slow flow) Head coil 2D projection MRA of ankle-feet Body coil 3D Bolus chase MRA: Renals  distal calf 3D phase contrast of renal arteries
  • Slide 12 - Unsubtracted Subtracted 3 Critical Details Positioning Bolus timing Subtraction
  • Slide 13 - Bolus Chase MRA Technique 2D Projection MRA (timing): 1 min Floating Table 7 min Sag Loc 1 min Axial Loc 3 min Cor 3D-Gd-MRA Pre 1.5 min During 1.5 min 3D phase contrast (renals) 7 min Total Imaging Time 15 min Total Exam Time <1 hr
  • Slide 14 - 2D Projection MRA: ankle-feet Right Left Coronal T1 Raw image Complex subtraction
  • Slide 15 - 2D Projection MRA: + complex subtraction Knee Ankles
  • Slide 16 - 2D Projection MRA (Left foot) 20.3 sec 32.5 sec 28.4 sec 24.4 sec 72.7 sec Time to fill distal station = 24 seconds Time to fill pelvis = 2/3 (24 sec) = 16 sec Time for venous contamination = 60 sec
  • Slide 17 - Calculation of Bolus-Chase Injection Timing Parameters Time to fill pelvis = 16 seconds 6 Station 1 = pelvis Station 2 = thigh Station 3 = calf scan delay Centers of k-space Time to venous contamination = 60 seconds 0 10 30 45 65
  • Slide 18 - Bolus Chase MRA Preparations level legs secure feet with curlex determine length of stations landmark above umbilicus
  • Slide 19 - Position for Overlap at Critical Sites Overlap Common Femoral Bifurcation Overlap Trifurcation
  • Slide 20 - Bolus Chase Positioning
  • Slide 21 - Selecting Imaging Parameters Slice thickness = 3 (2-5) mm # of slices = 28 (20-40) Frequency = 256 Phase = 160 (128-256) Phase FOV = 0.8 (1-0.6) Bandwidth = 31 (31 or 62)
  • Slide 22 - 3D Gadolinium Bolus Chase MRA Breathhold 1st station Use oxygen liberally Scan delay ~ 10 sec
  • Slide 23 - Image Post Processing Digital subtraction: pre from post Complex Fourier Subtraction Do not subtract MIPs MIP subtracted source images Reformat into lateral & oblique projections Subvolume MIPs for selected regions renal arteries mesenteric arteries common femoral bifurcations regions of greatest interest Examine pulsatility artifact on 2D TOF images
  • Slide 24 - Oblique views obtained by reformatting data on computer even after patient leaves Oblique MIP Coronal MIP
  • Slide 25 - Popliteal Artery Aneurysm Male>>> female Risk of complications thrombosis => high emboli => high rupture => low Associated with other aneurysms
  • Slide 26 - Patient could not straighter knee 2D Projection MRA
  • Slide 27 - Peripheral Vascular MRA Year # Patients Technique Sensitivity Specificity Owen (NEJM) 1992 23 2D TOF superior to DSA Baum (JAMA) 1995 155 2D TOF 82 84 Prince (Radiology) 1995 43 3D Gd 94 98 Snidow (Radiology) 1996 32 3D Gd 100 98 Hany (Radiology) 1997 39 3D Gd 93-96 96-100 Ho (Radiology) 1998 28 Bolus chase 93 98 Meaney (Radiology) 1998 20 Bolus Chase 81-89 91-95 Yamashita (JMRI) 1998 20 3D Gd 96 83 Lee (Radiology) 1998 23 2D Gd 94 91 Winchester (JMRI) 1998 22 2D Gd 90 98 Link (Radiology) 1999 67 3D Gd 100 83 (post stent)
  • Slide 28 - Reporting
  • Slide 29 - ppt slide no 29 content not found
  • Slide 30 - ppt slide no 30 content not found
  • Slide 31 - ppt slide no 31 content not found
  • Slide 32 - Useful Descriptors Descriptor Meaning Occluded Severe stenosis > 75% narrowing Moderate stenosis 50-75% Mild stenosis < 50% narrowing Normal normal Widely patent wide open: +/- tortuosity +/- atherosclerotic irregularity Ectatic  diameter < 50% more than normal Aneurysmal  diameter > 50% over normal
  • Slide 33 - Useless Descriptors Descriptor Meaning Stenotic “I think there is a stenosis” Patent “I see the artery”
  • Slide 34 - MRA Summary No Ionizing Radiation No Contrast Injection necessary If Contrast  No nephrotoxicity Reformat to obtain an view Anatomy and Physiology High Accuracy Tremendous Future

Description : Available Peripheral Vascular MR Angiography powerpoint presentation for free download which is uploaded by search an active user in belonging ppt presentation Health & Wellness category.

Tags : Peripheral Vascular MR Angiography

Shortcode : Get Shareable link