Myocardial Perfusion SPECT

E. Gordon DePuey, MD St. Luke’s-Roosevelt Hospital, New York, NY

Standard Myocardial Perfusion SPECT Protocols and Associated Patient Radiation Doses

Myocardial perfusion single-photon emission computed tomography (SPECT) is a well-established, highly standardized test to detect significant coronary artery disease and to risk-stratify patients with regard to cardiac event-free survival. Recently there have been significant advancements in scintillation camera hardware and software that allow for decreased image acquisition times and considerably lower injected radiopharmaceutical activity, resulting in lower patient radiation doses. Moreover, there has been a recent emphasis on patient-centered imaging, whereby SPECT imaging protocols are tailored to specific patient needs and diagnostic expectations. These patient-centered protocols have been designed to preserve or improve image quality and, when possible, also decrease patient radiation dose.

 Study Injected Activity  Effective Dose Estimate 
1-day rest/stress 99mTc based 10 mCi rest
30 mCi stress
9.3 mSv 99mTc tetrofosmin
11.4 mSv 99mTc sestamibi
1-day stress/rest 99mTc based 10 mCi stress
30 mCi rest
9.3 mSv 99mTc tetrofosmin
11.4 mSv 99mTc sestamibi
2-day stress/rest or rest/stress 99mTc based 25 mCi stress
25 mCi rest
11.6 mSv 99mTc tetrofosmin
14.8 mSv 99mTc sestamibi
Stress-only 99mTc based  25 mCi stress 5.8 mSv 99mTc tetrofosmin
6.8 mSv 99mTc sestamibi
1-day 201Tl rest/99mTc based stress 3.5 mCi 201Tl
25 mCi 99mTc m
21.2 mSv 201Tl /99mTc tetrofosmin
22.1mSv 201Tl /99mTc sestamibi
1-day stress/redistribution 201Tl 3.5 mCi 201Tl stress 15.3 mSv
1-day stress/reinjection/redistribution 201Tl 3.0 mCi 201Tl stress
1.0 mCi 201Tl reinjection
19.7 mSv
Attenuation correction
   X-ray CT
< 0.3 mSv
< 1 mSv

Recommendations to Decrease/Limit Patient Radiation Exposure