Optical methods for tympanic membrane colour and shape assessment
2004 (English)Licentiate thesis, comprehensive summary (Other academic)
Otitis media is one of the most common diseases of childhood. Increasing antibiotic resistance has lead to awareness of the importance of the diagnostic accuracy in otitis media. The recommended treatment of acute otitis media (AOM) involves antibiotics whereas in otitis media with effusion (OME) it does not. Hence, there is a need for new technology that can help separating between the two (and healthy conditions). The work in this thesis suggests a combination of diffuse reflectance spectroscopy and a new technique for surface-curvature measurement as a tool for assisted diagnosis in otitis media.
Diffuse reflectance spectroscopy was applied to estimate the degree of tympanic membrane erythema by means of two erythema detection algorithms from the literature. Measurements were performed in children with otitis media with effusion (15 ears) and in a healthy reference group (15 ears). The children with OME were scheduled for tympanostomy tube placement, which involves perforation of the tympanic membrane. Spectroscopic recordings were performed before and after perforation of the tympanic membrane in the OME group and once in the healthy reference group. Significant differences between the erythema estimates were present between the groups (p < 0.05).
A new surface-curvature measurement system, consisting of two parallel optical fibre arrays, was designed and tested using convex and concave polyacetal plastic (delrin) objects. By sequentially illuminating the surface and detecting the backscattered light intensity, a source-detector intensity matrix was formed. A simplified mathematical model for light scattering showed similar shape and amplitude of the source-detector matrices as did the experimental results. The surface-curvature measurement system distinguishes correctly between convex and concave surfaces.
Place, publisher, year, edition, pages
Linköping: Linköpings universitet , 2004. , 45 p.
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 1098
, LiU-TEK-LIC, 27
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-22164Local ID: 1283ISBN: 91-7373-973-1OAI: oai:DiVA.org:liu-22164DiVA: diva2:242477
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