1. Peripheral vessels. Could we replace conventional angiography? K. Genova National cardiology hospital Sofia

2. Peripheral vessels. Could we replace conventional angiography? Objectives To provide an overview of current clinical application of peripheral CT and MRI angiography Overview fundamental principles of MSCT technology Review strengths and limitations of MSCT Review the place, strengths, limitations of MRI peripheral angiography Bulgarian Endovascular Course 2011 2

3. Peripheral vessels. Could we replace conventional angiography? Current clinical indication Intermittent claudication Chronic Limb-threathenic ischemia Aneurysms Acute ischemia Follow-up and surveillance after surgical or percutaneous revascularization Vascular trauma Vascular mapping Other indications Bulgarian Endovascular Course 2011 3

4. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 4 Department of Health Western Australia.

5. Peripheral vessels. Could we replace conventional angiography? Current generation scanners Spatial resolution 0.4 mm - conventional angiography 0.15-0.25 mm Temporal resolution (shutter speed) improved to 83 msec (64-MDCT SSR); 60msec (Dual-Source CT DSR) – conventional angiography 6 msec Up to 64 slices in one rotation- 128-236-320 Larger coverage- speed of table movement increased thus widening range of the study Less contrast is required Bulgarian Endovascular Course 2011 5

6. Peripheral vessels. Could we replace conventional angiography? CT angiography allows: Acquisition of high-resolution volumetric date sets (near-isotropic voxels) that can be viewed in multiple planes Variety of visualization techniques (MPR, curved MPR, MIP, volume rendering) Grater speed of scanning with increase longitudinal coverage Detected non-vascular findings To visualize segments of arteries distal to occlusion that were not visible on routine DSA Bulgarian Endovascular Course 2011 6

7. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 7 Transverse volumetric data sets

8. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 8 VRT images

9. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 9 MIP images

10. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 10 Intraluminal analyses Axial image

11. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 11 Intraluminal analyses Axial image MIP

12. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 12 Postoperative evaluation Occlusion of the left branch Occlusion of the distal anastomosis of the right branch Collaterals Visualize segments of arteries distal to occlusion MIP- images

13. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 13 VRTIntraluminal analyses

14. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 14 VRTThrombosis of AP dex

15. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 15 MIP

16. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 16 Intraluminal analyses

17. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 17 MIPVRT

18. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 18 MIP Intraluminal analyses

19. Peripheral vessels. Could we replace conventional angiography? 19 Author No. of patients No. of analyzed segments No. of detectors Reported sensitivity (%) Reported specificity (%) Assessed segments Stenosis category (%) Poletti et al. 2004 12144482/96ns >50 Portugaller et al. 2004 5074049283Total treearea >70 Romano et al. 2004 423,40249395Total treens Romano et al. 2004 221,78249294Total treens Stueckle et al. 2004 52ns482100Total treens Edwards et al. 2005 441,02447993Total tree50–99 Fraioli et al. 2006 751,425496–9994–96Total tree50–99 Schertler et al. 2005 17170169690Popliteo-crural>50 Willmann et al. 2005 391,3651696 Total tree>50 Unpooled mean9194 Validity of CT angiography in peripheral arterial disease (PAD) Bulgarian Endovascular Course 2011

20. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 20 Limitations of peripheral CT angiography Image interference from calcified arteries Need for potentially nephrotoxic contrast agent Radiation exposure

21. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 21 Technical consideration for peripheral MR angiography Improvement in spatial resolution-(0.7-0.8mm in- plane; 1-3mm through-plane); reduction in the SNR Increase anatomic coverage (multi-station protocol, continuously moving table date acquisition, Total imaging matrix-Tim RF receiver coil) Increase speed of image acquisition- parallel imaging, high performance gradients

22. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 22 MRI techniques used for peripheral MR angiography Vessel wall (black-blood) imaging Contrast-enhanced MRA (3D gradient echo sequences- FLASH, SPGR, FFE, RF-FAST) Non Contrast-Enhanced MRA Time-of-Flight MRA Steady-State Free Precession MRA Phase-Contrast MRA

23. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 23 Vessel wall (black-blood) imaging Black-blood ECG-gated TSE image in axial plane of the level of mid left thigh AFS-absence of atherosclerotic disease

24. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 24 Contrast-enhanced MRA- 3D gradient-echo Four-station peripheral CE-MRA- multistation moving-table technique Coronal plane The positioning of the volumes are critical to avoid the exclusion of vascular territories Overlap between sequential volumes Correct timing of image acquisition in relation to contrast injection to ensure adequate arterial opacification

25. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 25 Contrast-enhanced MRA- 3D gradient-echo Continuously moving table technic peripheral CE-MRA (MIP) High-quality large FOV Full anatomic coverage Lack of discontinuity artifacts Reduction of the time for planning the examination on two date sets (FastView and VesselScout) Higher spatial resolution of the two lower stations- better visualization of the small arterial vessels

26. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 26 3D coronal MIP peripheral CE-MRA Three-step multistation protocol Continuously moving table technic

27. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 27 Non Contrast-enhanced MRA (NCE-MRA) Time-of-flight MRA- most commonly used NCA- MRA technic for peripheral vessels (2D TOF, 3D TOF) Flow-related enhancement; suppressed background signal Scanning plan- perpendicular to the vessels ECG-gating- systolic gating to time the image acquisition during the peak blood flow

28. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 28 Non Contrast-enhanced MRA (NCE-MRA) 2D TOF MRA Occlusion of the AFS bilateraly Collaterals from profunda fem. Flow in the calves throgh collateral arteries

29. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 29 Non Contrast-enhanced MRA -TruFISP ECG-gated

30. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 30 Time-resolved MRA or dedicated CE-MRA To reduce venous contamination at the level of the distal station (calf and pedal vessels) in patients with rapid AV transit times The dynamic visualization of contrast in the vessels At least one acceptable angiographic date sets at the level of distal vessels Better delineation of distal bypass Better visualization of collateral vessels AV-shunts, malformation, high-vascularized tumor etc.

31. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 31 Time-resolved MRA initialintermediatelate

32. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 32 Time-resolved MRA The vascular malformation enhances late compared with the arteries and that there are no large draining veins. This is a low-flow vascular malformation.

33. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 33 Dedicated CE-MRA MIP reconstruction High-vascularised Tu of the left calf

34. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 34 Time-resolved MRA or dedicated CE-MRA VRT reconstructions in different planes

35. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 35 Diagnostic accuracy of CE-MRA for the detection of significant stenosis in patients with known or suspected PAD

36. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 36 Major advantages and disadvantages of the principal diagnostic modalities employed for clinical imaging of peripheral vessels

37. Peripheral vessels. Could we replace conventional angiography? Bulgarian Endovascular Course 2011 37 Suggested diagnostic algorithm in patients with known or suspected peripheral artery disease