Suggested CT Protocols for Inclusion in Cardiac SPECT/CT Protocols
| Protocol | Parameter | Comments |
|---|---|---|
| Low-dose cardiac CT | Indications | Coronary artery calcium (CAC) scoring; attenuation correction |
| CT overview (topogram) | 140–180 mm | |
| CT scan (tomogram) | Electrocardiographic gating mandatory for CAC scoring | |
| Field of view | Sternum–thoracic spine (140–180 mm) | |
| Acquisition | Diastolic phase | |
| Tube current | 20–40 mA | |
| Tube voltage | 130 kV | |
| Slice thickness | ≤3 mm; increment of ≤3 mm | |
| Breathing protocol | Breath holding | |
| Radiation dose (in addition to that of SPECT) | 1–3 mSv | |
| Diagnostic cardiac CT (64-slice CT) | Indications | CT coronary angiography |
| CT scan (tomogram) | Electrocardiographic gating mandatory | |
| Field of view | Sternum–thoracic spine (140–180 mm) | |
| Acquisition | Diastolic phase | |
| Scan delay | “Smart preparation” (∼10 s after start of intravenous injection of contrast material [100 mL]; flow rate of 4 mL/s) | |
| Tube current | ≤900 mA | |
| Tube voltage | 130 kV | |
| Collimation | Thinnest possible collimation necessary for optimal 3-dimensional reconstructions | |
| Slice thickness | ≤3 mm; increment of ≤3 mm; thinnest possible slice thickness with overlap in reconstruction increment necessary for optimal 3-dimensional reconstructions | |
| Breathing protocol | Breath holding | |
| Radiation dose (in addition to that of SPECT) | 4–14 mSv |