RadteraCT Liver (Triphasic / Multiphase)
CT+ ContrastAbdomen & Pelvis
Indications
- Characterization of liver lesions (HCC, FNH, adenoma, hemangioma, metastases)
- HCC surveillance/diagnosis in cirrhosis (LI-RADS)
- Pre/post locoregional therapy or resection planning
Patient prep
- NPO 4 h
- 18-20G IV antecubital for high flow; check renal function
- Neutral or no oral contrast (positive oral contrast can obscure)
- Arms up; supine
Contrast
Agentiodinated (iohexol 350 / iopamidol 370)
RouteIV
DoseWeight-based ~1.5 mL/kg or ~100-150 mL at 4-5 mL/s + saline chase
TimingNon-contrast; late arterial ~35 s (bolus-tracking + ~15-20 s delay); portal venous ~65-75 s; +/- delayed ~3-5 min (for hemangioma fill-in, washout/capsule on LI-RADS, cholangiocarcinoma)
Technique
- Supine, arms up; coverage diaphragm through liver (extend to pelvis if staging)
- Bolus tracking ROI in aorta; late arterial phase is key for hypervascular tumors
- 120 kV (100 kV thin for iodine boost); dose modulation
- Thin recon 1.25-3 mm; coronal reformats
- Breath-hold each phase
Series / Sequences
| # | Series / Sequence | Plane | Thickness | Notes |
|---|---|---|---|---|
| 1 | Non-contrast axial | axial | 2.5-5 mm | Baseline density, calcification, fat, hemorrhage |
| 2 | Late arterial axial | axial | 2.5-3 mm | Hypervascular lesion/HCC arterial enhancement (~35 s) |
| 3 | Portal venous axial | axial | 2.5-3 mm | Washout, hypovascular mets (~65-75 s) |
| 4 | Delayed axial | axial | 2.5-3 mm | Hemangioma fill-in, washout/capsule, cholangiocarcinoma (when indicated) |
| 5 | Coronal reformat | coronal | 2-3 mm | Overview |
Key points
- Late arterial phase timing is critical for HCC detection—too early misses tumor enhancement
- Apply LI-RADS in at-risk (cirrhosis) patients: arterial hyperenhancement, washout, enhancing capsule
- Add delayed phase for hemangioma (peripheral nodular discontinuous fill-in) and cholangiocarcinoma (progressive enhancement)
- Weight-based contrast dosing optimizes hepatic enhancement
- MRI with hepatobiliary agent complements when CT is indeterminate
References
• ACR LI-RADS CT/MRI v2018
• ACR-SAR-SPR Practice Parameter for CT of the Abdomen
• Radiopaedia: multiphase liver CT ( link
• ACR-SAR-SPR Practice Parameter for CT of the Abdomen
• Radiopaedia: multiphase liver CT ( link
Source: Researched — verify against your institution
Reference template — verify and adapt to your scanner, vendor and institution before clinical use. Not a substitute for clinical judgment.