What Causes Hyperresonance?

What Causes Hyperresonance? Hyperresonant sounds may also be heard when percussing lungs hyperinflated with air, such as may occur in patients with COPD, or patients having an acute asthmatic attack. An area of hyperresonance on one side of the chest may indicate a pneumothorax. Tympanic sounds are hollow, high, drumlike sounds. What does Hyperresonance mean