A single-session PCCT workflow successfully combined coronary CTA, carotid imaging, lung assessment, and delayed cardiac imaging within one consolidated examination.
The protocol integrated UHR coronary PCCTA (0.2 mm) with a high-pitch thoraco-cervical acquisition (0.4 mm), maintaining diagnostic image quality while controlling radiation and iodine exposure.
The approach demonstrated high diagnostic yield in an asymptomatic high-risk cohort, detecting substantial burdens of coronary atherosclerosis, carotid plaque disease, lung nodules, and emphysema in a single imaging session.
Figure 2. ACTA protocol workflow illustrating the combined acquisition strategy: non-contrast CAC scoring, UHR coronary CTA, rapid thoraco-cervical high-pitch sweep, and delayed ECG-triggered late iodine enhancement imaging.
Source: De Gori et al., European Heart Journal – Imaging Methods and Practice, 2026.
Access full publication
Examination protocol
Section | Details |
|---|
Scanner | Dual-source photon-counting CT (Naeotom Alpha; Siemens Healthineers®) with cadmium-telluride detectors; 0.25-s rotation; collimation by phase: 120 × 0.2 mm for UHR coronary acquisitions and 144 × 0.4 mm for the high-pitch thoraco-cervical sweep and the 5-min delayed phase (QuantumPlus full-spectral mode). |
Patient positioning | Supine with arms above the shoulders in a slightly oblique position to reduce overlap of carotids and mediastinum; baseline BP and HR measured; beta-blockers and/or nitroglycerin as indicated; single breath-hold with instruction not to swallow; beam-hardening mitigation with IMAR. |
Acquisition phases | - Non-contrast CAC: lung apices to L3, prospective ECG-triggered.
- UHR CCTA: 120 kVp, retrospective ECG-gated, pitch 0.2.
- High-pitch thoraco-cervical sweep (FLASH): ≤3.2 s, pitch 3.2, caudo-cranial (lung bases→orbital floor), prospective ECG-triggered.
- Late iodine enhancement (LIE, 5 min): heart + breasts, prospective ECG-triggered in diastole.
|
Additional acquisition | Low-dose expiratory scan to quantify air-trapping in COPD or in smokers with ≥20 pack-years. |
Contrast protocol | Three-phase IV injection using iomeprol-400 or iopromide-370: - Phase 1: 0.7 mL/kg undiluted contrast at 5–6 mL/s.
- Phase 2: 0.5 mL/kg contrast + 0.5 mL/kg saline at 3–4.5 mL/s.
- Phase 3: 50 mL saline.
Total for a 70-kg patient: 84 mL (49 mL undiluted + 35 mL mixed phase). |
Iodine dose | ≈33.6 g (0.48 gI/kg) with iomeprol-400; ≈31.08 g (0.44 gI/kg) with iopromide-370. |
Scan parameters | Tube potential: 120 kVp for CCTA; 140 kVp for medium-resolution thoraco-cervical acquisitions and the 5-min delayed phase. Collimation: 120 × 0.2 mm (UHR CCTA) Quantum HD 144 × 0.4 mm (FLASH & LIE) QunatumPlus CARE Dose 4D + CARE keV with reference IQ level 64; prospective ECG-triggering for CAC, FLASH, and LIE; retrospective ECG-gating for CCTA; combined DLP ≈ 740 mGy·cm (effective dose ≈ 11–13 mSv). |
Image reconstruction | - Coronaries: 0.2-mm slices at 0.1-mm intervals, 10242 matrix, Bv60, QIR level 4, ZeeFree.
- Thoracic/cervical angiography: 0.4-mm slices at 0.2-mm spacing, 7682 matrix.
- Cine images for cardiac function: 1.5-mm slices, 1-mm interval across 20 cardiac phases (0–95%) on a 512 matrix.
|
Spectral post-processing | VMI at 40 keV (contrast amplification) and 70 keV (calcium subtraction); iodine maps for pulmonary perfusion and ECV; virtual non-contrast (VNC); iodine–VNC fusion images; pure lumen reconstructions for stenosis quantification. |
Reconstruction software | ReconCT (syngo.via VB80C). |
BP, blood pressure; CAC, coronary artery calcium; CCTA, coronary CT angiography; COPD, chronic obstructive pulmonary disease; ECG, electrocardiogram; ECV, extracellular volume; HR, heart rate; LIE, late iodine enhancement; DLP, dose-length product; UHR, ultra-high resolution; VMI, virtual monoenergetic images.
De Gori C, Aimo A, Latorre L, et al. Single-session photon-counting CT protocol for simultaneous screening of coronary and carotid artery disease and lung pathology. Eur Heart J Imaging Methods Pract. 2026;4(1):qyag074.
