CT findings of thymic cysts with different densities and their pathological basis
QIU Liyan1, JIN Zhonggao2, JIA Xiupeng3, HU Bibo1, JIN Yinhua1, ZHENG Jianjun1
1.Department of Radiology, Ningbo Hwa mei Hospital, University of Chinese Academy of Sciences, Ningbo NO.2 Hospital, Ningbo 315010, China; 2.Department of Radiology, Ningbo NO.7 Hospital, Ningbo 315010, China; 3.Ningbo Diagnostic Pathology Center, Ningbo 315021, China
QIU Liyan,JIN Zhonggao,JIA Xiupeng, et al. CT findings of thymic cysts with different densities and their pathological basis[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2020, 50(2): 154-157.
Abstract:Objective: To explore the CT manifestations of thymic cysts with different densities and their pathological basis. Methods: The CT findings and pathological changes of 45 cases of thymic cysts with solid density and 23 thymic cysts with liquid density confirmed by operation and pathology were retrospectively analyzed. Results: There was a correlation between the density of thymic cysts and the distribution of size (P<0.01). The shape of the solid density cysts was regular, while the liquid density cyst was irregularly shaped along the large vessel gap. There was a significant difference between different groups (P<0.01). However, tear droplets and triangles were found in both groups without significant difference in the distribution between the two groups (P>0.05). Compared with the liquid density cysts, the solid density cysts were mostly not herniated outside the thymus profile, and the difference was statistically significant (P<0.01). The pathologic features of solid density thymic cysts included pseudostratified ciliated columnar epithelium or ciliated columnar epithelium with secretory function, dense arrangement of the epithelial cells of the cyst wall, and turbid cystic fluid. The surface of the liquid density thymic cysts was composed mainly of non-secretory flattened or columnar epithelium, sparse or even absent, the weak base layer and usually clear cystic fluid. There was significant difference between cyst density and epithelial type (P<0.05). Conclusion: The imaging findings of the solid density thymic cysts were different from liquid density thymic cysts. Their pathologic basis was helpful to understand the different manifestations of thymic cysts.
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