Validation of kVp measurement using the HVL approach for standard beam qualities for mammography

Abstract

In mammography imaging, the most common target material used in mammography machines are Molybdenum (Mo) target with Mo filters. In the publication of International Electrotechnical Commission (IEC) 61267, the establishment of mammography beam qualities assembly are given in 3 fixed parameters namely the target material which is Mo, the Mo filter thickness and the tube voltage. While, Mo target with rhodium (Rh) filters combination standard beam qualities were established by the Physikalish-Technische Bundesanstalt (PTB) primary standard Laboratory. The objective of this study is to measure the kVp and HVL ranging from 23-31 kV. Later compare the displayed kilovoltage peak (kVp) on the control panel with the kVp measured using a non-invasive kVp meter and validating them with the HVL measurement. From the results, the kVp dialed and kVp measured shows significant difference by 2-4 kV. The HVL measured for the kVp before and after corrected also shows similar pattern, where the HVL after kVp is correct is almost identical to the standard beam qualities with the difference of 1%. This verifies that the kVp measurement using a non-invasive kVp meter can be validated with just a simple measurement of its HVL for mammography standard beam qualities.