Radiation dose and image noise evaluation in coronary computed tomography angiography (CCTA) using an iterative...

Area of Science:

• Medical Imaging
• Radiology
• Cardiovascular Imaging

Background:

• Coronary computed tomography angiography (CCTA) is crucial for diagnosing coronary artery disease.
• Radiation dose is a significant concern in CCTA procedures.
• Iterative reconstruction (IR) algorithms offer potential for dose reduction.

Purpose of the Study:

• To evaluate radiation dose reduction in CCTA using an iterative reconstruction (IR) algorithm.
• To assess the impact of the IR algorithm on image noise and quality.
• To determine optimal settings for dose reduction in CCTA.

Main Methods:

• 47 patients underwent CCTA on a 64-slice multi-detector CT.
• Patients were divided into groups based on iDose installation and acquisition protocol (prospective/retrospective ECG-gated).
• Reduced-dose images were reconstructed using two levels (L4, L6) of the iDose4 IR algorithm; image noise was measured.

Main Results:

• Retrospective acquisition with iDose4 L6 achieved comparable noise to full-dose filtered back-projection at 46% lower dose.
• Prospective acquisition with iDose4 L4 and L6 showed noise reduction (16% and 30%) with a 26% dose decrease.
• Image quality was improved with reduced radiation exposure.

Conclusions:

• Reduced radiation exposure in CCTA is feasible without compromising image quality.
• Further dose reduction in CCTA is possible.
• Combining iDose4 with prospective acquisition can significantly lower CCTA radiation doses to approximately 2 mSv or less.