Evaluation of radiation dose accuracy calculated using IndoseCT software with direct measurement on polyester-resin phantoms

Abstract

The current study aims to compare the radiation doses (size-specific dose estimate, SSDE) calculated using IndoseCT software and dose measurements obtained with a pencil ionization chamber on in-house phantoms of different sizes. In-house phantoms with different diameters (i.e. 8, 16, 24, and 32 cm) were constructed using polyester-resin (PESR) as the main ingredient and methyl ethyl ketone peroxide (MEKP) as a catalyst. Axial images of the phantoms were used to calculate the SSDE using IndoseCT software. In addition, doses were direcly measured using a pencil ionization chamber. The scan parameters were 120 kVp tube voltage, 100 mA tube current, and 1 s tube rotation. Measurements were carried out at each hole within the in-house phantoms. The SSDE calculated using IndoseCT was comparable to the dose measured using a pencil ionization chamber. The percentage differences of the doses from IndoseCT and a pencil ionization chamber were 9.83, 3.11, 2.10, and 0.47% for phantom diameters of 8, 16, 24, and 32 cm, respectively. The size-specific dose calculated using IndoseCT is accurate. The percentage difference between the doses calculated using IndoseCT and measured doses using a pencil ionzation chamber on in-house phantoms of diameters 8–32 cm were within ±10%.