Imaging Features of Primary Mediastinal Cysts

Objective To study the imaging features of primary mediastinal cysts,and to improve the diagnostic ability of these diseases.Methods The imaging findings of primary mediastinal cysts proved by pathlolgy in 42 cases were retrospectively.All of cases underwent posteroanterior and lateral views of chest.The plain and contrast-enhanced CT scans were performed in 28 and 15 cases.MRI examination was done in 6 cases.The location,size,shape,density,edge,wall and adjacent structures of the primary mediastinal cysts were observed.According to imaging features all of cases was divided into typical group and atypical group.Results The mediastinal cysts were located in anterior mediastinum in 28 cases,in middle mediastinum in 7 cases,in posterior mediastinum in 7cases.Bronchogenic cyst was in 9 cases.Cystic lymphangioma was in 4 cases.Thymic cyst was in 11 cases.Pericardial cyst was in 5 cases.Mature cystic teratoma was in 13 cases.The typical group was in 38 cases.The atypical group was in 4 cases.Conclusion 90% of the typical primary mediastinal cysts can be diagnosed.The final diagnosis of the atypical group desponds on pathology.