Image Evaluation of Nasopharyngeal Mucosa Physical Change of Laryngopharyngeal Reflux Disease

Abstract

Objectives: Evaluate a picture of narrow band imaging (NBI) examination for a diagnosis of laryngopharyngeal reflux disease (LPRD) using the image processing analysis objectively. Methods: Ten patients who underwent NBI were studied. Eight patients were LPRD and 2 patients were non-LPRD patients. We performed image processing for pictures after NBI examination by using the application software of a perfect translation invariance complex discrete wavelet transform (PTI-CDWT) developed at Toyohashi University of Technology and MATLAB (The MathWorks, Inc.). We looked into the nasopharyngeal mucosa physical changes that were detected by PTI-CDWT and analyzed by MATLAB. Results: Images with LPRD showed many round opaque dots mostly consistent with round wavelet transform. On the contrary, images without LPRD represented a small number of linear lines, and any other area showed no feature. Morphologic operation by MATLAB distinguished the difference of nasopharyngeal mucosa physical exchange between LPRD and non-LPRD. Conclusions: Though LPRD is a common disease for otolaryngologists to see, it may not yet be a definite diagnosis like gastroesophageal reflux disease. We have presented a correlation between LPRD and nasopharyngeal mucosa examination as mackerel cloud pattern at American Academy of Otolaryngology—Head and Neck Foundation annual meetings. We showed the possibility of image processing to diagnose LPRD with PTI-CDWT last year. Images which were implemented morphological operation by MATLAB may show representative for each nasopharyngeal mucosa physical change. MATLAB characterized images which were modified using PTI-CDWT. To use PTI-CDWT and MATLAB is not only useful in diagnosing LPRD but may possibly allow one to develop image diagnosis or an analysis instrument.