Evaluation of Dose Homogeneity in Cone-Beam Breast Computed Tomography

Radiat Prot Dosimetry. 2017 Aug 1;175(4):473-481. doi: 10.1093/rpd/ncw375.

Abstract

The aim of this study is to determine, via measurements on phantoms and Monte Carlo (MC) simulations, the dose distribution of absorbed dose in a cone-beam breast computed tomography scan. The absorbed dose volume distribution was measured inside a polyethylene cylindrical phantom, simulating adipose breast tissue, using LiF:Mg,Ti thermoluminescence dosimeters. A reasonable agreement (between 2 and 8%) between the simulated and measured data was observed. The 3D distribution of absorbed dose was evaluated at 40, 60 and 80 kV in a phantom simulating a pendant breast. MC simulations indicate a significantly lower spread of volume dose than in mammography. The dose variation along the radial distance in the simulated phantoms was in the range of 4‒14%. These findings might be useful when devising models for breast imaging dose assessment that take into account the uneven distribution of the glandular mass in the breast volume.

MeSH terms

  • Breast / diagnostic imaging*
  • Cone-Beam Computed Tomography*
  • Female
  • Humans
  • Monte Carlo Method
  • Phantoms, Imaging
  • Radiation Dosage*
  • Radiometry