MRI-based volumetric assessment of cardiac anatomy and dose reduction via active breathing control during irradiation for left-sided breast cancer

Cardiac MRI demonstrated a significant reduction in LV myocardium irradiated with the use of ABC. The correlation between reduction in V22.5 values for LV wall and CT-defined whole heart suggests that CT is adequate for determining which patients are likely to benefit from ABC treatment, but inaccuracies inherent to standard CT dictate that more detailed imaging studies such as MRI are required for accurate cardiotoxicity assessment.