Image evaluation of nasopharyngeal mucosa physical changes
of Laryngopharyngeal reflux disease (LPRD)
Hideo Niwa, MD, PhD1, Satoshi Horihata PhD2, Chong Huei Shan3, Zhong Zhang3, Yasuhide Makiyama, MD, PhD1
Nihon University School of Dentistry at Matsudo Department of 1Head and Neck Surgery, 2Mathematical Science
3
Toyohashi University of Technology instrumentation System Laboratory
Objectives
To evaluate a picture of Narrow Band Image (NBI) examination for a diagnosis of LPRD
using the image processing analysis objectively.
Methods and Materials
Five patients who underwent NBI were utilized. Three patients were LPRD patients
and two 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 wavelet transform complex discrete wavelet transform
(PTI-CDWT) developed at Toyohashi University of Technology and MATLAB® (The
MathWorks,Inc.). We looked into the feature of nasopharyngeal mucosa physical
changes which were detected by PTI-CDWT and analyzed by MATLABR.
Results
Images with LPRD showed many round opaque dots consitstent with round wavelet
transform mostly. On the contrary, Images without LPRD represented small number
of linear line and any other area showed nothing feature. Morphological operation by
MATLAB® distinguished the difference of nasopharyngeal mucosa physical exchange
between LPRD and Non-LPRD.
Conclusion
Though LPRD is a common disease for otolaryngologist, it may not be still a definite
diagnosis like GERD so far. We have presented a correlation between LPRD and
nasopharyngeal mucosa examination as mackerel cloud pattern at AAOHNS annual
meetings. We showed possibility of image processing to diagnose LPRD with PTICDWT 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 by using PTI-CDWT. To use PTICDWT and MATLAB® is not only useful to diagnose LPRD but may have possibility to
develop image diagnosis or analysis instrument.
Five patients who underwent NBI examination were
utilized. Three pictures were LPRD patients and Two
pictures were non-LPRD patients.
All pictures after NBI examination were performed imageprocessing with the application software of a perfect
translation invariance complex wavelet transform complex
discrete wavelet transform (PTI-CDWT) developed at
Toyohashi University of Technology and analyzed with
MATLAB2013®application software (The MathWorks,
Inc.) .
 We looked into the feature of nasopharyngeal mucosa
physical changes which were detected by PTI-CDWT
(Figure 1 to 5) and analyzed by MATLAB® morphological
operation (Figure 6 to 10).
Level-
Level- LevelLH 3
HH3
HL
Level-2
Level-2
LH
HH
Level1
LH
 LPRD (Laryngopharyngeal reflux disease) is very common
disease. However, LPRD is still hard to diagnose due to poor
objective findings without specific features with fiberscope
examination of larynx.
 We have reported a specific correlation between
nasopharyngeal mucosa epithelial change and LPRD
patients by using NBI (Narrow band imaging) examination at
AAO HNS.
1
 To analyze NBI digital pictures, we studied NBI digital
pictures which were represented nasopharyngeal mucosa of
LPRD with MATLAB® application software.
Fig. 2. Exchange to grey-scale
Fig. 3.2D-CDWT
Fig. 14.LPRD case 2
HL
Level1
HH
Fig. 4. Sharpness
Fig. 5. Noise reduction
Fig. 6.Binarization
Fig. 15.LPRD case 3
Fig.7.Diagonal
fill
to
eliminate 8-connectivity
of the background
 NBI is getting more recognized as an early cancer detection
tool but also NBI has a possibility for diagnosis of benign
disease such as inflammation and capillary disease as well.
 Analysis of NBI digital pictures focused on morphological
changes of nasopharyngeal mucosa epithelial underlined
one feature of LPRD with the perfect translation invariance
complex wavelet transform complex discrete wavelet
transform (PTI-CDWT). PTI-CDWT advocates an image
processing such as noise reduction, enhancement, and
detention.
Fig. 12.Normal nasopharyngeal mucosa
Fig. 13.LPRD case 1
Level-2
LevelFig.
HL 3 1. NBI digital picture
 First of all, I would like to modify and correct it with
presentation, as submitted abstract is different.
Fig. 11.Normal nasopharyngeal mucosa
Fig. 8.Bridges unconnected
pixels
Fig.10.Shrinks objects to
points. It removes pixels
so that objects without
holes shrink to a point,
and objects with holes
shrink to a connected ring
halfway between each
hole and the outer
boundary.
Fig. 9.Sets a pixel to 1 if
five or more pixels in
neighborhood are 1s;
otherwise, it sets the
pixel to 0.
 All of Image processing pictures of LPRD showed many round
opaque dots which consitstent with polyhedral cells and a
superficial row of rounded cells of nasopharyngeal cells which
we call this distinctive pattern mackerel cloud pattern. On the
contrary, Non-LPRD pictures represented small number of linear
line and any other area showed nothing feature (Figure.11 to15).
 Morphological operation by MATLAB® distinguished the differene
of particular nasopharyngeal mucosa physical exchange between
LPRD and non-LPRD.
 Image processing information on part of light reflex of NBI pictures
could not be detected though PTI-CDWT are applied for image
processing.
 We have presented a correlation between LPRD and nasopharyngeal mucosa examination as mackerel cloud pattern through NBI examination. Image
processing which were implemented morphological operation by MATLAB® showed representative for a status of nasopharyngeal mucosa physical
change. MATLAB® characterized images which were modified with PTI-CDWT. We are currently finding out the best way to deal with the loss of image
processing information on the part of light reflex of NBI pictures. However, a utilization of PTI-CDWT and MATLAB® is not only useful to diagnose
LPRD but may have possibility to develop image diagnosis or analysis instrument.
Contact
<your name> HIDEO NIWA MD, PhD
<your organization> Nihon University School of Dentistry Department of Head and Neck Surgery
Email:[email protected]
Phone:81-47-360-9341
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