As the patient says '99' several times, distorted '99' auscultated sounds indicate healthy lung areas. A clear nasal ‘99” indicates an area of density. Use the slider to reveal the lungs with the normal area highlighted.
Skin and Ribs

Blended View


Move slider to reveal lungs

Ask the patient to say "99" several times while auscultating the chest walls. Over healthy lung areas, "99" is not understandable. This is because sound is impeded in normal lungs.

Compare this voiced breath sound to the recording in the "Bronchophony - Abnormal" lesson.