Computed tomography of the lungs of healthy captive red-footed tortoises (Chelonoidis carbonaria)

Abstract

Respiratory tract diseases of various origins are commonly diagnosed in captive testudines. In tortoises, computed tomography is considered the method of choice for evaluation of the lung. Our objective was to describe the anatomy of the lung parenchyma of red-footed tortoises (Chelonoidis carbonaria) using computed tomography to estimate the normal radiodensity of the lung and lung volume. We selected 10 healthy adult red-footed tortoises of similar size. Computed tomography images were obtained using lung window settings and multiplanar reconstructions for quantitative evaluation using the histogram method. The tortoises were not sedated and were allowed to maintain their head and limbs retracted during the exam. Data were expressed in mean and standard deviation. In testudines, the lung is divided into left and right, and there are no lobes. There is a main bronchus in each lung. Mean values for radiodensity and lung volume were −811.30 ± 19.82 Hounsfield units and 942.12 ± 189.29 cm³, respectively. These findings can be useful as a normal range for evaluating red-footed tortoises in a clinical setting. It also serves as a basis for future studies regarding specific patterns in lung disease.