Computed tomography and three dimensional anatomical study of the liver in the chinchilla (Chinchilla lanigera)

Few instances of neoplastic formations in the liver of chinchillas have been found, even though the species is widely used in different scientific experiments. In the present article we investigate the anatomical features of the chinchilla's liver using CT and three dimension (3D) imaging. For the trials we used 12 (six males and six females) clinically healthy chinchillas all at 18 months of age. The animals were positioned in dorsal recumbency. We used Th8 to L2 vertebrae and the sternum as bone markers for the transverse CT study. The investigated anatomical landmarks for the CT coronal study were the vertebrae, costal arch, soft abdominal wall, diaphragm, stomach and the right kidney. 3D reconstructions were accomplished with a specific imaging software. On transverse and coronal CT images, the chinchilla's liver was composed of lobus hepatis sinister lateralis, 'middle lobe'-without proper Latin term in NAV 2017, lobus hepatis dexter and lobus caudatus. The 'middle lobe' was separated into the 'left middle lobe' and the 'right middle lobe'. Lobus hepatis dexter consisted of lobus hepatis dexter medialis and lobus hepatis dexter lateralis. There was an anatomical relation between the liver, fundus ventriculi and corpus ventriculi. Proc. caudatus was in close contact with the right kidney. Vesica fellea was elongated and ellipsoid. 3D reformatted images confirmed the results obtained by transverse and coronal CT studies. The CT density of the liver in HU was 195.6 ± 73.1. The CT and 3D reconstructed images were visualized at high resolution. This data could be used as a basis for further morphological and imaging studies.

Spontaneous pneumomediastinum and macklin effect: Three rare case reports with computed tomography findings

Spontaneous pneumomediastinum (SPM) is defined as free air or gas in the mediastinum that is not associated with an obvious cause such as chest trauma. The SPM results from acutely elevated intra-alveolar pressure: The high-pressure gradient between the distal alveoli and the pulmonary interstitium leads to alveolar rupture. This causes free gas to separate through the peribronchovascular fascial sheaths (interstitial emphysema) into the hilum and then into the mediastinum. Once the gas is in the mediastinum, it can travel up to the cervical soft tissues (even the retroperitoneum) producing subcutaneous emphysema. The Macklin effect appears on thoracic computed tomography (CT) as linear air collections adjacent to bronchovascular sheaths. This case report presents CT findings of SPM due to the Macklin effect in three cases and a brief literature review on this subject.