Acoustic rhinometry: a new diagnostic procedure--experimental and clinical experience.

The diagnostic value of transnasal acoustic reflection measurements (Rhinoklack) was investigated in an experimental and clinical study. Within the range of nasal and epipharyngeal dimensions, in vitro and in vivo measurements showed satisfactory reproducibility. A simple maneuver helps to identify the transition from the rigid nasal cavity to the movable epipharynx. The location and the amount of nasal obstruction can be verified and traced back to their morphologic correlative. The effect of decongestion on nasal volume was measured for normal mucosa (41% enlargement) and mucosa altered by scar formation after septoplasty and turbinoplasty (21% enlargement). After maxillomandibulary advancement of 10 mm for obstructive sleep apnea, the EV index representing epipharyngeal volume (EV) showed an average increase of 6 cm3.