Technical note: Skin thickness measurements using high-resolution flat-panel cone-beam dedicated breast CT.

Area of Science:

• Radiological Physics
• Medical Imaging
• Biomedical Engineering

Background:

• Accurate breast skin thickness is essential for precise radiation dosimetry in mammography.
• Dedicated breast CT (bCT) offers high-resolution imaging for detailed anatomical measurements.
• Previous studies have established reference values, but validation in diverse populations and with advanced imaging is needed.

Purpose of the Study:

• To determine the mean and range of location-averaged breast skin thickness using high-resolution dedicated breast CT.
• To provide data for Monte Carlo-based estimation of normalized glandular dose coefficients.
• To assess the influence of breast pathology on skin thickness measurements.

Main Methods:

• Retrospective analysis of 137 dedicated breast CT datasets from 136 women.
• Utilized an algorithm to calculate location-averaged mean breast skin thickness.
• Investigated variations in skin thickness based on pathology results (benign, malignant, hyperplasia).
• Evaluated the impact of surface fitting for breast curvature.

Main Results:

• The mean breast skin thickness was 1.44 ± 0.25 mm, with a range of 0.87–2.34 mm.
• Measurements showed excellent agreement with prior research.
• No statistically significant differences in skin thickness distributions were found across different pathologies (benign, malignant, hyperplasia).

Conclusions:

• The established mean breast skin thickness of 1.44 mm is appropriate for breast dosimetry, consistent across different systems and populations.
• Breast pathology did not significantly alter location-averaged mean breast skin thickness in this cohort.
• Accurate estimation of breast skin thickness requires consideration of breast curvature.