This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory Radiology, Subject name: Radiology
Spinnaker sign is a feature of 
Select and explain. 
A. Pleural effusion, B. Pneumothorax, C. Pneumomediastinum, D. Fracture of bronchus
C: Pneumomediastinum
Answer: C: Pneumomediastinum 
Explanation: Thymic sail sign is the normal appearance of thymic shadow abutting the Hea shadow seen on Chest X ray of a normal Infant Spinnaker sail sign is the lifting of the Thymic shadow with the lucency of air between Thymus and Hea in cases Of Pneumomediastinum thymus sail sign- normal spinnaker sign