Cordella Alessia, Saunders Jimmy H, Stock Emmelie
Department of Morphology, Imaging, Orthopedics, Rehabilitation and Nutrition, Gent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
Vet Sci. 2023 Mar 4;10(3):192. doi: 10.3390/vetsci10030192.
The thymus is a lymphatic mediastinal organ that is largely subject to changes with age. In human patients, the CT characteristics of the thymus in children and adults is well described. Furthermore, it is known in human medicine that stress can lead to a reduction in the size of the thymus, followed by a phase of hyperplasia (called the 'rebound effect'). The visualization of thymic tissue in the cranial mediastinum of adult dogs with neoplasia is possible and could be related to a similar effect. In this study, we aimed to describe the CT characteristics of the thymus in adult dogs with neoplasia and to compare the aspect of the thymus in these dogs to juvenile dogs with a presumed normal thymus. A total of 11 adult dogs with neoplasia and 20 juvenile dogs were included. Several CT features of the thymus were evaluated, including the size, shape, and pre- and post-contrast attenuation values. The overall appearance was lobulated in all of the adult dogs and homogeneous in all of the juvenile dogs; it was left-sided in all of the adult dogs, while it was located in the midline in a few of the juvenile dogs (right-sided only in one). The thymus was less attenuating in adult dogs, in some cases with negative minimum pre-contrast attenuation values. In some dogs with neoplasia, the thymus can be detected at CT examination despite their age.
胸腺是一种纵隔淋巴器官，其大小在很大程度上会随年龄变化。在人类患者中，儿童和成人胸腺的CT特征已有详尽描述。此外，在人类医学中已知，压力会导致胸腺体积缩小，随后进入增生期（称为“反弹效应”）。成年患肿瘤犬颅纵隔内胸腺组织的显影是可能的，这可能与类似效应有关。在本研究中，我们旨在描述成年患肿瘤犬胸腺的CT特征，并将这些犬的胸腺表现与假定胸腺正常的幼年犬进行比较。总共纳入了11只成年患肿瘤犬和20只幼年犬。对胸腺的几个CT特征进行了评估，包括大小、形状以及增强前后的衰减值。所有成年犬的胸腺整体外观呈分叶状，所有幼年犬的胸腺呈均匀一致；所有成年犬的胸腺位于左侧，而部分幼年犬的胸腺位于中线（仅1只位于右侧）。成年犬的胸腺衰减较低，在某些情况下，平扫时最小衰减值为负值。在一些患肿瘤的犬中，尽管其年龄较大，但在CT检查时仍可检测到胸腺。
