PET/CT images and their quantitative analysis and the pictorial representation of IBAT. (a) Quantitative analysis of PET/CT images for IBAT volume in the four studied groups. Data are mean ± SD; p < 0.001 as compared to the control (asterisk), cold-exposed (dagger), and propanolol-treated (double dagger) rats. (b) 3-D PET images of IBAT: ventral, dorsal, and caudal views. (c) Pictorial representation of the lateral and dorsal views of IBAT showing a bilateral structure where the medial portions (a) are located near or between T3 and T4 and extends posteriorly and bifurcates (b) and tapers until T6.