Sequential Helical-Axial-Helical Triple-Rule-Out CT Angiography: Technical Feasibility and Territory-Specific Image...

Area of Science:

• Radiology
• Medical Imaging
• Cardiovascular Imaging

Background:

• Conventional triple-rule-out CT angiography (TRO-CTA) protocols face challenges in optimizing contrast enhancement across pulmonary, coronary, and aortic circulations due to conflicting timing requirements.
• Acute chest pain evaluation requires simultaneous assessment of multiple potential pathologies, necessitating efficient and accurate imaging techniques.

Purpose of the Study:

• To evaluate a physiology-based sequential helical-axial-helical acquisition strategy for TRO-CTA.
• To determine if this sequential protocol can achieve consistent tri-territory vascular enhancement in emergency department patients with acute chest pain.

Main Methods:

• Retrospective analysis of 71 emergency department patients undergoing TRO-CTA with a structured sequential protocol (pulmonary, coronary, aortic phases).
• Individualized test-bolus timing guided the sequential acquisition.
• Objective (vascular attenuation, SNR, CNR) and subjective image quality assessments were performed by two radiologists.

Main Results:

• Mean vascular attenuation exceeded diagnostic thresholds in all three territories (pulmonary, coronary, aortic).
• Diagnostic interpretability was achieved in all territories in every examination without repeat contrast imaging.
• Good to excellent interobserver agreement was noted for subjective image quality scores.

Conclusions:

• A sequential physiology-based TRO-CTA strategy is technically feasible and provides consistent enhancement across all three vascular territories in an emergency setting.
• Further prospective comparative and outcome-based studies are needed to confirm the clinical impact of this imaging strategy.