Magnetic resonance imaging of thymic cyst

(A) Axial, balanced steady-state free precession sequence chest magnetic resonance image shows a sharply marginated, thin-walled, high-signal mass in the retrosternal, anterior mediastinal region (arrow). (B) Sagittal, single-shot, fast-spin echo, breath-hold sequence confirms the anterior mediastinal, retrosternal, high-signal, cystic mass (arrow).