Computed tomography and magnetic resonance imaging are potential noninvasive methods for evaluating the cisterna chyli in cats.

Abstract

OBJECTIVE: There is limited information on the normal appearance of the cisterna chyli (CC) in cats on CT and MRI. The aim of this retrospective study was to describe the CT and MRI characteristics of the CC in a group of cats without lymphatic system pathology. SAMPLE: A total of 31 CT and 63 MRI images were obtained of client-owned cats between January 2017 and March 2022. METHODS: The presence, location, shape, maximum width, MRI-signal intensity, mean attenuation, and contrast enhancement of the CC were recorded from CT and MRI scans. RESULTS: The CC was identified in all the CT scans and in 60 MRI studies. The CC was located level with the cranial mesenteric artery in 56 of 91 cases. It was crescent shaped in 34 of 54 cases. On precontrast CT images, the mean attenuation of the CC was 17 HU, and the mean postcontrast attenuation was 28 HU. On T2-weighted sequences, the CC was isointense to CSF and hyperintense to the muscles, while on T1-weighted images, it was isointense to the muscles. Contrast enhancement was variable in both techniques. CLINICAL RELEVANCE: CT and MRI have the potential for noninvasive evaluation of CC in cats.