Coupling Pressure Sensing with Optical Coherence Tomography to Evaluate the Internal Nasal Valve

Purpose: To evaluate endoscopic long-range optical coherence tomography system combined with a pressure sensor to concurrently measure internal nasal valve cross-sectional area and intraluminal pressure. Methods: A pressure sensor was constructed using an Arduino platform and calibrated using a limiter-controlled vacuum system and industrial absolute pressure gauge. Long-range optical coherence tomography imaging and pressure transduction were performed concurrently in the naris of eight healthy adult subjects during normal respiration and forced inspiration. The internal nasal valve was manually segmented using Mimics software and cross-sectional area was measured. Internal nasal valve cross-sectional area measurements were correlated with pressure recordings. Results: Mean cross-sectional area during forced inspiration was 6.49 mm(2). The mean change in pressure between normal respiration and forceful inspiration was 12.27 mmHg. The direct correlation between pressure and cross-sectional area as measured by our proposed system was reproducible among subjects. Conclusions: Our results demonstrate a direct correlation between internal nasal valve cross-sectional area and nasal airflow during inspiration cycles. Endoscopic long-range optical coherence tomography coupled with a pressure sensor serves as a useful tool to quantify the dynamic behavior of the internal nasal valve.