1 / 36

George Segall, M.D.

Stanford University. PET Myocardial Perfusion Imaging: Protocols and Procedures. George Segall, M.D. PET Perfusion Agents. Diffusible tracers. Radioisotope Form Half-life MeV. Rubidium-82 ( 82 Rb) Chloride 75 sec 3.15 Nitrogen-13 ( 13 N) Ammonia 10 min 1.19

elina
Télécharger la présentation

George Segall, M.D.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Stanford University PET Myocardial Perfusion Imaging: Protocols and Procedures George Segall, M.D.

  2. PET Perfusion Agents Diffusible tracers Radioisotope Form Half-life MeV Rubidium-82 (82Rb) Chloride 75 sec 3.15 Nitrogen-13 (13N) Ammonia 10 min 1.19 O-15 (15O) Water 110 sec 1.72 Copper-62 (62Cu) PTSM 9.8 min 2.94 Potassium-38 (38K) Chloride 7.6 min 2.70 Carbon-11 (11C) Butanol 20 min 0.96 PTSM, pyruvaldehyde methylthiosemicarbazone

  3. Medicare Coverage Policy 1995 Rb-82 PET for myocardial perfusion 1998 F-18 deoxyglucose PET and SPECT for myocardial viability 2003 N-13 ammonia for myocardial perfusion

  4. Medicare Coverage Policy for Rb-82 and N-13 ammonia PET whether at rest alone, or rest with stress, is approved when PET is • performed in place of SPECT, or • used following SPECT when results are equivocal, technically uninterpretable, or discordant with clinical care SPECT may not be used following an inconclusive PET

  5. RAM License Strontium-82 200 mCi Rubidium-82 200 mCi Strontium-85 1000 mCi

  6. Rb-82 Infusion System

  7. Relative Advantages Rb-82 N-13 ammonia Availability Excellent Limited Logistics Easy Difficult Cost Fixed Variable

  8. Decision Analysis On-site cyclotron Occasional Imaging N-13 ammonia and PET/CT capacity Daily Imaging Rb-82 chloride and

  9. Decision Analysis Flexibility Exercise Regadenoson Adenosine N-13 ammonia Dipyridamole Dobutamine Convenience Regadenoson Rb-82 chloride Adenosine Dipyridamole

  10. Scheduling Rb-82 chloride N-13 ammonia scheduled > 1D in advance √ √ • problematic cases inconclusive SPECT high BMI √ scheduled day of exam • ED and inpatients

  11. Emission protocol N-13 ammonia • 20-30 mCi • 2D gated emission • start 10 min p injection Rb-82 chloride • 40-60 mCi • 2D gated emission • start 90 sec p injection

  12. 2D vs 3D Gated Rb-82 PET Knesaurek. BMC Nucl Med 2007;7:4 16 normal volunteers had resting Rb-82 on a BGO PET camera Low dose (20 mCi) 3D acquisition compared to high dose (60 mCi) 2D acquisition

  13. Emission Reconstruction Rb-82 chloride • reconstruction filter: Butterworth 0.4 roll-off / power 10 • post reconstruction: axial smoothing N-13 ammonia • reconstruction filter: Butterworth 0.40 roll-off / power 10 • no post reconstruction smoothing

  14. CT protocol • 140 keV • 30-210 mAs (noise index 25.0) • pitch 0.5 • ungated

  15. PET Perfusion Agents •Rb-82 Chloride and N-13 ammonia are both extractable agents which passively diffuse across cell membranes •Both tracers have high first-pass myocardial extraction fractions, which are inversely related to flow is a non-linear manner.

  16. Rb-82 chloride Tang. Phys Med Biol 2009;54:3161-3171 •Rb-82 is rapidly cleared from the circulation

  17. N-13 ammonia •N13 is rapidly cleared from the circulation

  18. N-13 ammonia •N-13 ammonia is trapped in the myocardium from the action of glutamate dehydrogenase1 and glutamine synthetase2 NH3 -ketoglutarate 2 1 13NH4+ 13NH3 13NH3 glutamine glutamate glutamine urea

  19. PET Perfusion Agents Relationship to CBF Rb-82 Chloride N-13 ammonia Schelbert Hr, Schwaiger M. In: PET and Autoradiography. Eds: Phelps ME, Mazziotta JC, Schelbert H 1986 Bergman SR. In: PET of the Heart. Eds: Bergmann SR, Sobel BE. 1992

  20. Rb-82 40-60 mCi 60 55 50 45 40 35 30 25 0 20 15 10 5 N-13 ammonia 20-30 mCi Work Flow inject inject Pers scan CT scan min CT scan scan Pers inject inject

  21. 60 55 50 45 40 35 30 25 0 20 15 10 5 Rb-82 chloride inject inject Pers scan CT scan min scan scan Aden CT inject inject

  22. 60 55 50 45 40 35 30 25 0 20 15 10 5 Rb-82 chloride inject inject Pers scan CT scan min scan scan Reg CT inject inject

  23. inject inject scan CT scan Pers min 60 55 50 45 40 35 30 25 0 20 15 10 5 inject inject 25 0 20 15 10 5 CT scan Ex CT scan 90 85 80 75 70 65 60 ••• min N-13 ammonia

  24. = inject 60 55 50 45 40 35 30 25 0 20 15 10 5 Injection times Cyclotron starts production 23 minutes prior to calibration time Ex Reg Ad Per Dob

  25. Normal Rb-82 perfusion study

  26. Normal Rb-82 perfusion study

  27. Normal Rb-82 perfusion study

  28. Normal Rb-82 perfusion study

  29. Abnormal Rb-82 perfusion study

  30. Abnormal Rb-82 perfusion study

  31. Normal N-13 perfusion study

  32. Normal N-13 perfusion study

  33. Abnormal N-13 perfusion study 72 year old man with peripheral vascular disease. Coronary arteriography: •LAD: 60% ostial and 80% mid vessel stenoses •LCX: 90% proximal stenosis and occluded OM •RCA: 90% ostial stenosis

  34. Summary • PET myocardial perfusion protocols are simple and easy to incorporate in most practices • Rb-82 and N-13 ammonia are qualitatively equivalent

  35. Summary • High throughput, and low cost per patient makes Rb-82 PET practical in a high volume practice • NH3-ammonia PET is better suited for occasional use in patients with inconclusive SPECT, or as the test of choice in problematic patients

More Related