SPECT (single photon emission computed tomography) – advantages and disadvantages
Important advantages of SPECT are that it has been extensively validated and has a good sensitivity, compared to other methods of assessment of myocardial viability. Cost of SPECT is lower than PET (positron emission tomography) imaging and is more widely available than PET in most regions. SPECT can be used in the presence of cardiac implantable electronic devices (CIED) while cardiac magnetic resonance (CMR) imaging has important limitations in this setting.
SPECT has a much higher cost compared to echocardiography and less availability compared to echo. Spatial resolution of SPECT is limited. There is a potential difficulty in interpreting SPECT results in patients with three vessel disease and balanced myocardial ischemia  as the SPECT interpretation depends on comparing the counts between normal abnormal regions. Compared to CMR and echocardiography, SPECT has some radiation risk, though not very high.
- Emad F et al. Triple vessel coronary artery disease presenting as a markedly positive stress electrocardiographic test and a negative SPECT-TL scintigram: a case of balanced ischemia. Heart Int. 2011 Sep 29; 6(2): e22.