Wintrich's Sound Change

Wintrich's Sound Change, in percussion of the chest, occurs when there is a cavity communicating with a bronchus, and consists of the fact that when the patient breathes with an open mouth, the percussion tone increases, and when the mouth is closed, it decreases. The presence of Wintrich's sign is a reliable indicator for diagnosing a cavity, provided that open pneumothorax, inflammatory infiltration of the corresponding lobe of the lung, or its compression by a limited pleural exudate can be excluded, as it is also observed in these conditions. Unlike Williams' tracheal tone (see), Wintrich's sound change is noted in both superficial and deep percussion. It is explained by the acoustic law, according to which open hollow bodies, when their walls are vibrated, produce a higher tone than closed ones.