TU‐G‐204‐08: Investigation of Volume Adjustment Techniques in Low Dose CT Lung Densitometry

TL;DRAbstract

Purpose: Low dose CT for lung densitometry has shown utility in evaluating severity and progression of pulmonary emphysema in patients with chronic obstructive pulmonary disease (COPD). Effort is underway at QIBA to standardize measurement protocols based on published longitudinal studies on non‐diseased subjects. The purpose of this report is to assess an important component of the densitometry CT data interpretation: the volume adjustment necessary to reduce the effect of respiration on density. Methods: The 15 percentile density scores (Perc 15), defined as a threshold HU containing 15% lowest density in the attenuation histogram of the whole lung, were compiled for 30 subjects obtained from the National Lung Cancer Trial database with baseline and repeat scans one year apart. A model assuming an adapted sponge model, where the relationship between volume (V) and density (rho) is given by m=rhoV^s (Staring et al, Med. Phys. 41, 021905 (2014)). s can be obtained for each subject, and

Chat with Paper

AI Agents for this Paper