Software Development for Estimating the Conversion Factor (K-Factor) at Suitable Scan Areas, Relating the Dose Length...

Area of Science:

• Medical Physics
• Radiological Sciences

Background:

• Accurate estimation of radiation dose in computed tomography (CT) is crucial for patient safety.
• Existing methods for determining radiation dose, such as using standardized k-factors, may lack flexibility for diverse scanning protocols.
• The International Commission on Radiological Protection (ICRP) provides reference k-factors, but these might not cover all clinical scenarios.

Purpose of the Study:

• To develop and validate a software tool, k-factor-creator software (kFC), for calculating CT k-factors in arbitrary scan areas.
• To assess the reliability of kFC-derived k-factors by comparing them with established ICRP values.
• To confirm the clinical utility of kFC by evaluating effective doses in coronary computed tomographic angiography (CCTA).

Main Methods:

• Development of k-factor-creator software (kFC) to derive k-factors from effective dose and dose-length product.
• Utilized Imaging Performance Assessment of CT scanners and CT-EXPO software for data generation.
• Validated kFC-derived k-factors against ICRP publication 102.
• Conducted a phantom study for coronary computed tomographic angiography (CCTA) to evaluate effective dose using both ICRP and kFC k-factors.

Main Results:

• The kFC software was developed to provide k-factors for CT examinations across arbitrary scan areas.
• Comparison with ICRP publication 102 indicated reliable k-factor estimations from kFC.
• In CCTA, effective dose estimations using kFC (5.26 mSv) closely matched phantom study results (5.28 mSv), showing only a 1% difference.
• ICRP k-factors resulted in a significantly lower effective dose estimation (2.57 mSv, 51% difference) compared to the phantom study.

Conclusions:

• The k-factor-creator software (kFC) provides accurate and reliable k-factors for CT examinations, even in non-standard scan areas.
• kFC-derived k-factors demonstrate significant utility in clinical practice by enabling precise effective dose determination, as shown in CCTA.
• The flexibility of kFC in adapting to various scan regions makes it a valuable tool for optimizing radiation dose management in diverse CT applications.