Noninvasive optical diagnosis of bacteria causing otitis media

Currently, the identification of the bacteria responsible for acute otitis media requires a painful invasive procedure: tympanocentesis. To develop a rapid and noninvasive technique for bacterial diagnosis, the fluorescence profiles of four common pathogens and the optical characteristics of the tympanic membrane have been investigated. Each bacterium produces a unique in vitro fluorescence profile when measured in a saline suspension. Also, spectrally resolved transmission measurements from the chinchilla tympanic membrane demonstrate an optical window that will transmit sufficient light for in vivo measurement of the fluorescence profiles. Thus, we have established the precept for a fluorescence-based bacterial diagnosis technique to be used in otitis media. This paper presents the theory, optical data, and a discussion of the device engineering involved in the technique.