liu.seSearch for publications in DiVA
Change search
ReferencesLink to record
Permanent link

Direct link
In vitro tympanic membrane position identification with a co-axial fiber optic otoscope
Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
Linköping University, Department of Clinical and Experimental Medicine, Oto-Rhiono-Laryngology and Head & Neck Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of ENT - Head and Neck Surgery UHL.
Linköping University, Department of Biomedical Engineering, Biomedical Instrumentation. Linköping University, The Institute of Technology.
2011 (English)In: Journal of Biomedical Optics, ISSN 1083-3668, Vol. 16, no 9, 097002- p.Article in journal (Refereed) Published
Abstract [en]

Otitis media diagnosis can be assisted by measuring the shape of the tympanic membrane. We have developed an ear speculum for an otoscope, including spatially distributed source and detector optical fibers, to generate source-detector intensity matrices (SDIMs), representing the curvature of surfaces. The surfaces measured were a model ear with a latex membrane and harvested temporal bones including intact tympanic membranes. The position of the tympanic membrane was shifted from retracted to bulging by air pressure and that of the latex membrane by water displacement. The SDIM was normalized utilizing both external (a sheared flat plastic cylinder) and internal references (neutral position of the membrane). Data was fitted to a two-dimensional Gaussian surface representing the shape by its amplitude and offset. Retracted and bulging surfaces were discriminated for the model ear by the sign of the Gaussian amplitude for both internal and external reference normalization. Tympanic membranes were separated after a two-step normalization: first to an external reference, adjusted for the distance between speculum and the surfaces, and second by comparison with an average normally positioned SDIM from tympanic membranes. In conclusion, we have shown that the modified otoscope can discriminate between bulging and retracted tympanic membranes in a single measurement, given a two-step normalization. (C) 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.3622486]

Place, publisher, year, edition, pages
SPIE - International Society for Optical Engineering, 2011. Vol. 16, no 9, 097002- p.
Keyword [en]
otitis media, acute otitis media, tympanic membrane, surface shape
National Category
Engineering and Technology
URN: urn:nbn:se:liu:diva-13011DOI: 10.1117/1.3622486ISI: 000296707100033OAI: diva2:17661
Funding agencies|Swedish Agency for Innovation Systems (VINNOVA) through the Swedish National Center of Excellence for NonInvasive Medical Measurements (NIMED)||Available from: 2008-03-20 Created: 2008-03-20 Last updated: 2011-12-02
In thesis
1. Optical Methods for Tympanic Membrane Characterisation: Towards Objective Otoscopy in Otitis Media
Open this publication in new window or tab >>Optical Methods for Tympanic Membrane Characterisation: Towards Objective Otoscopy in Otitis Media
2008 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Otitis media, which is an upper respiratory tract infection that affect the middle ear, is the second most common disease in childhood, outnumbered in prevalence only by the common cold. Diagnosis of middle ear inflammation is often performed in the primary healthcare where the normal procedure involves anamnesis and physical examination of the tympanic membranes (TM) of the patient, usually be means of otoscopy. The general aim of this thesis was to develop optical methods that enable quantification of TM characteristics associated with otitis media. Diffuse reflectance spectroscopy was applied to quantify TM erythema using previously suggested erythema detection algorithms. Healthy TM:s were significantly distinguished from TM:s with induced erythema (p < 0.01) and from TM:s in ears with mucous middle ear effusion (p < 0.05). A new technique for surface shape assessment based on an on-axis dual fibre array incorporated in an otoscope was developed and evaluated in ear models and on tympanic membranes from harvested temporal bones. The technique utilises the combined effects of source-detector fibre separation and fibre-to-sample distance on the detected light intensity.

Optical phantoms, both polyacetal plastic solids and latex membranes, were utilised to demonstrate the ability of the surface shape assessment technique to differentiate between convex and concave surfaces – as a bulging tympanic membrane is typically associated with acute otitis media whereas a retracted eardrum is associated with otitis media with effusion. Monte Carlo simulations of the surface shape data were performed in order to validate the experimental results with a theoretical model that are consistent with light transport theory. Retracted and bulging tympanic membranes from harvested temporal bones could be separated with a single measurement, given that variations in measurement distance were accounted for and that measurement from normally positioned tympanic membranes were used for signal normalization. In conclusion, the studies implicate that for individual otitis diagnosis, the hyperaemic tympanic membrane was separated from the healthy by application of erythema indices using diffuse reflectance spectroscopy. Moreover, bulging and retracted positions of the tympanic membrane were separable by means of the source-detector intensity matrix. For further clinical studies it is reasonable to assume that data from both methods are needed for diagnosis.

Place, publisher, year, edition, pages
Institutionen för medicinsk teknik, 2008. 97 p.
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1173
Optical Methods, Spectroscopy, Surface Curvature, Monte Carlo, Tympanic Membrane, Otitis Media
National Category
Medical Laboratory and Measurements Technologies
urn:nbn:se:liu:diva-11246 (URN)978-91-7393-933-1 (ISBN)
Public defence
2008-04-11, Berzeliussalen, Ingång 65, plan 9, Campus US, Linköpings universitet, Linköping, 13:00 (English)
Available from: 2008-03-20 Created: 2008-03-20 Last updated: 2009-05-14

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Peebo, MarkusStrömberg, Tomas
By organisation
Department of Biomedical EngineeringThe Institute of TechnologyOto-Rhiono-Laryngology and Head & Neck SurgeryFaculty of Health SciencesDepartment of ENT - Head and Neck Surgery UHLBiomedical Instrumentation
In the same journal
Journal of Biomedical Optics
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 345 hits
ReferencesLink to record
Permanent link

Direct link