Algorithm for radiation dose reduction with helical dual source coronary computed tomography angiography in clinical...

Area of Science:

• Medical Imaging
• Radiology
• Cardiovascular Imaging

Background:

• Reducing radiation dose in coronary computed tomography angiography (CCTA) is crucial for cardiac CT.
• Maintaining diagnostic image quality alongside dose reduction is a primary challenge.

Purpose of the Study:

• To decrease radiation dose during helical dual-source CCTA.
• To develop and validate a patient-based algorithm for dose reduction by optimizing tube voltage, full tube current (FTC) window, and tube current outside the FTC window.

Main Methods:

• Compared FTC at 70% of the cardiac cycle (FTC70) to a 45%-75% window (FTC45-75) using 100 and 120 kVp.
• Applied FTC70 in patients with heart rates <70 bpm, no arrhythmia, age <65 years; 100 kVp was used for BMI <30, low coronary calcium score (CCS), and no stents.
• Assessed objective and subjective image quality.

Main Results:

• Radiation dose reduction of 66% at 100 kVp and 43% at 120 kVp was achieved with FTC70 compared to FTC45-75 at 120 kVp.
• 99% of segments in the FTC70 group achieved diagnostic quality.
• Image quality metrics (noise, SNR, CNR) were comparable between FTC70 and FTC45-75; BMI, CCS, and heart rate variation predicted image quality.

Conclusions:

• A validated patient-based algorithm for helical CCTA radiation dose reduction using dual-source CT (DSCT) has been successfully developed.
• The algorithm effectively reduces radiation dose while preserving diagnostic image quality in clinical practice.