hyperresonant

Hyperresonant is an adjective used to describe a percussion sound that is abnormally loud and lower pitched compared with normal resonance. In clinical examination, a hyperresonant percussion note suggests increased air content in the examined tissue or space, such as hyperinflated lungs, or a space where tissue is reduced or absent. The sound is typically described as booming and is often noted on one side or region of the chest.

In medical practice, hyperresonance is most commonly associated with conditions that increase air in the lungs or pleural space. Pneumothorax, particularly when air accumulates rapidly, can produce unilateral hyperresonance with diminished breath sounds. Chronic obstructive pulmonary disease and asthma can also show bilateral hyperresonance due to hyperinflation of the lungs. By contrast, conditions that involve fluid or solid tissue, such as pneumonia or pleural effusion, usually yield dull or flat percussion notes rather than hyperresonant ones.

Limitations include the subjective nature of percussion and the influence of technique, patient body habitus, and examiner experience. Hyperresonance alone is not diagnostic and should be interpreted in conjunction with other findings such as auscultation, imaging, and clinical presentation.

Outside of medicine, hyperresonant can occasionally appear in acoustics or engineering to describe a system with an amplified resonant response at certain frequencies, though this usage is less common in clinical contexts.

Etymology derives from hyper- meaning excessive and resonant meaning producing a vibrating sound.