Direct Analysis of Pathogenic Structures Affixed to the Tympanic Membrane during Chronic Otitis Media

Abstract

Objective To characterize otitis media-associated structures affixed to the mucosal surface of the tympanic membrane (TM) in vivo and in surgically recovered in vitro samples. Study Design Prospective case series without comparison. Setting Outpatient surgical care center. Subjects and Methods Forty pediatric subjects scheduled for tympanostomy tube placement surgery were imaged intraoperatively under general anesthesia. Postmyringotomy, a portable optical coherence tomography (OCT) imaging system assessed for the presence of any biofilm affixed to the mucosal surface of the TM. Samples of suspected microbial infection-related structures were collected through the myringotomy incision. The sampled site was subsequently reimaged with OCT to confirm collection from the original image site on the TM. In vitro analysis based on confocal laser scanning microscope (CLSM) images of fluorescence in situ hybridization-tagged samples and polymerase chain reaction (PCR) provided microbiological characterization and verification of biofilm activity. Results OCT imaging was achieved for 38 of 40 subjects (95%). Images from 38 of 38 (100%) of subjects observed with OCT showed the presence of additional microbial infection-related structures. Thirty-four samples were collected from these 38 subjects. CLSM images provided evidence of clustered bacteria in 32 of 33 (97%) of samples. PCR detected the presence of active bacterial DNA signatures in 20 of 31 (65%) of samples. Conclusion PCR and CLSM analysis of fluorescence in situ hybridization-stained samples validates the presence of active bacteria that have formed into a middle ear biofilm that extends across the mucosal layer of the TM. OCT can rapidly and noninvasively identify middle ear biofilms in subjects with severe and persistent cases of otitis media.

Assessing the Effect of Middle Ear Effusions on Wideband Acoustic Immittance Using Optical Coherence Tomography

“…In general, biofilms tend to exhibit a stronger (brighter) OCT signal than the TM, and frequently appear as a distinct, additional, and layered structure affixed to the TM, based on OCT A-scan profiles ( Guder et al 2015 ; Nguyen et al 2010 , 2012 ). Nonetheless, in this study, the presence of MEEs and/or biofilm has not been biologically confirmed via invasive sampling as in the study from Monroy et al (2018) . Subjects in this study were outpatients who did not undergo any surgical procedure at the time of the visit.…”

Economical and compact briefcase spectral-domain optical coherence tomography system for primary care and point-of-care applications

“…Our group has previously used high-end 800-nm OCT systems for TM imaging, which has led to several new findings. [17][18][19]44 Here, we have shown representative skin images to test the applicability and feasibility of our system. The presented system, however, was not fully optimized for TM imaging, and efforts are being made to do so.…”

Non-Invasive Optical Screening of Streptococcus Pneumonia Based Inflammatory Changes of the Tympanic Membrane and Mastoid Mucosa in Guinea Pig Otitis Media Using Optical Coherence Tomography

“…Several successful middle ear-related OCT studies have been conducted, and have shown the exceptional capabilities of OCT in aiding the identification of sub-surface tissue differentiation and localization of critical structures [21]- [23]. Moreover, the thickness of the TM membrane can be visualized and quantitatively analyzed using OCT to delineate the relevant morphological structures [24]- [26]. Pre-identification of these morphological changes in vivo at an early stage not only offers a value from a research point of view, but may also be beneficial to understanding the changes that occur during the process of infection.…”