Effect of BMI-related Noise on Liver Fat Quantification and Coronary Artery Calcium Scoring in Electromagnetic X-ray Computed Tomography Images

This study investigated the effects of body mass index (BMI)-related noise simulation on coronary artery calcium score (CACS) and liver fat quantification in coronary artery computed tomography (CT) images, which are acquired using X-ray-based electromagnetic radiation. Noise maps extracted from obese patients were added to normal-weight images to generate virtual high-BMI conditions, allowing assessment of noise effects independent of anatomical differences. CACS was evaluated at four locations, and liver fat was quantified using liver attenuation, liver-to-spleen (L/S) ratio, and L/S difference. Across the virtual high-BMI datasets, approximately 71% of cases showed increased CACS and 57% demonstrated upward changes in risk rank. Liver fat assessment decreased by up to 1.98%, 6.69%, and 19.02% in liver attenuation, L/S ratio, and L/ S difference, respectively. These findings indicate that BMI-related noise, arising from increased attenuation of electromagnetic X-ray photons, can influence quantitative CT metrics and should be considered in clinical CT interpretation.