PET/CT Colonography Protocol
| Step | Details |
|---|---|
| Patient preparation | See Table 1 |
| CT overview scan (scout or topogram) | Covered area: head, neck, chest, and diaphragm |
| Chest PET/CT scan | Scan direction: caudocranial |
| Scan delay: 30 s after start of intravenous injection of 60 mL of contrast material* | |
| Scan from middle of liver to base of skull to ensure overlap | |
| Breathing protocol*: normal expiration if possible; otherwise, shallow breathing | |
| Tube current: 100 mA† | |
| Tube voltage: 130 kV† | |
| Slice thickness: 5 mm; increment: 2.5 mm† | |
| PET/CT colonography scan | CT overview scan (from middle of thighs to middle of thorax) |
| Administration of intravenous bolus of 20 mg of N-butylscopolamine (or glucagon) dissolved in 10 mL of saline | |
| Rectal enema with 2 or 3 L of tap water via rectal balloon catheter | |
| Patient position: prone, with rectal balloon catheter in place during scan | |
| If scan is longer than 15 min, additional 20 mg of N-butylscopolamine dissolved in 50 mL of saline is applied via short infusion during procedure | |
| Scan direction: caudocranial | |
| Scan delay: 50 s after start of intravenous injection of 80 mL of contrast material* | |
| Scan from upper thighs to middle of thorax | |
| Breathing protocol*: mild expiration if possible; otherwise, shallow breathing followed by expiration breath-hold when liver is reached | |
| Tube current: 100 mA† | |
| Tube voltage: 130 kV† | |
| Slice thickness: 3 mm; increment: 2.5 mm† |