Preferred Label : herniated mediastinal pleural sac sign;
Definition : Crescent-shaped lucency crossing the midline into a partially collapsed lung on a
frontal radiograph. Suggests pneuomothorax; gas-containing sac extends from mediastinal
pleural space to contralateral side, often with mediastinal shift.;
Source : Eisenberg, Ronald L. Atlas of Signs in Radiology.;
Origin ID : RID35269;
Associated condition(s)
Crescent-shaped lucency crossing the midline into a partially collapsed lung on a
frontal radiograph. Suggests pneuomothorax; gas-containing sac extends from mediastinal
pleural space to contralateral side, often with mediastinal shift.