Advances in technical aspects of myocardial perfusion SPECT imaging

Excerpt

Although myocardial perfusion SPECT (MPS) imaging is widely used in current clinical practice, it suffers from some fundamental limitations including long image acquisition, low image resolution, and patient radiation dose. In the last two decades, MPS was performed most commonly by standard dual-head scintillation cameras with parallel-hole collimators, typically configured in a 90° detector geometry and image reconstruction based on standard filtered-back projection algorithms. The required scan times were as along as 15-20 minutes for each stress and rest MPS acquisition to provide adequate imaging statistics, resulting in long overall test times and frequent artifacts caused by patient motion during the scan as well as compromised patient comfort. Recently, it has become very important to address these limitations, since MPS has new competitors in the non-invasive imaging arena most notably coronary CT angiography (CCTA), which allow diagnostic imaging in a very short time. In addition, a practice of combining MPS with other modalities such as CCTA for better diagnostic certainty1 has intensified concerns regarding total radiation dose delivered to the patient.2 The radiation dose and acquisition time are intrinsically linked with each other, as longer acquisition times could be used with lower injected doses and higher doses could be used to shorten acquisition times. …