Figure 2: Micro-CT analysis of effect of PTX on RILF. (a) Representative micro-CT images of irradiated or nonirradiated rats with or without PTX administration. PTX administration ameliorated the fibrotic changes including increased lung density (white arrowheads), decreased lung volume, and structural distortion of heart (white star) and lung lobes in irradiated rats. (b–d) Lung density (b), lung area (c), and cardiac right-lateral shift (d) of control (Cont) and irradiated (IR) rats at 16 weeks after irradiation. Data are expressed as the mean ± SEM . versus control group; versus IR group. Micro-CT, micro-computed tomography; PTX, pentoxifylline; RILF, radiation-induced lung fibrosis; HU, Hounsfield units.