Repositioning the Bolus Tracking ROI to the Superior Vena Cava in CTPA Facilitates Contrast Volume Reduction

This randomized controlled trial evaluates a protocol optimization for Computed Tomography Pulmonary Angiography (CTPA). The study investigates the impact of repositioning the bolus-tracking region-of-interest (ROI) from the standard pulmonary trunk (PT) to the superior vena cava (SVC). The goal is to compensate for the CT scanner's inherent transit delay time (TDT) to better align the scan with the peak arterial phase. By optimizing this timing, the study assesses whether contrast media volume can be safely reduced by 40% (from 50 ml to 30 ml) while maintaining diagnostic image quality and preventing venous contamination.

NCT Number	NCT07342374
Lead Sponsor	Hospital Queen Elizabeth, Malaysia Collaborators: Universiti Sultan Zainal Abidin
Conditions	Pulmonary Artery Embolism, Pulmonary Embolism (PE)
Enrollment	72 participants
Start Date	2023-02-01
Primary Completion	2024-12-16 (estimated)
Study Completion	2024-12-16 (estimated)
Updated on ClinicalTrials.gov	2026-01-15