Noninvasive in vivo optical detection of biofilm in the human middle ear

Abstract

Otitis media (OM), a middle-ear infection, is the most common childhood illness treated by pediatricians. If inadequately treated, OM can result in long-term chronic problems persisting into adulthood. Children with chronic OM or recurrent OM often have conductive hearing loss and communication difficulties and require surgical treatment. Tympanostomy tube insertion, the placement of a small drainage tube in the tympanic membrane (TM), is the most common surgical procedure performed in children under general anesthesia. Recent clinical studies have shown evidence of a direct correspondence between chronic OM and the presence of a bacterial biofilm within the middle ear. Biofilms are typically very thin and cannot be recognized using a regular otoscope. Here we report the use of optical coherent ranging techniques to noninvasively assess the middle ear to detect and quantify biofilm microstructure. This study involves adults with chronic OM, which is generally accepted as a biofilm-related disease. Based on more than 18,537 optical ranging scans and 742 images from 13 clinically infected patients and 7 normal controls using clinical findings as the gold standard, all middle ears with chronic OM showed evidence of biofilms, and all normal ears did not. Information on the presence of a biofilm, along with its structure and response to antibiotic treatment, will not only provide a better fundamental understanding of biofilm formation, growth, and eradication in the middle ear, but also may provide much-needed quantifiable data to enable early detection and quantitative longitudinal treatment monitoring of middle-ear biofilms responsible for chronic OM.optical coherence tomography | primary care imaging | low-coherence interferometry | otoscopy | otolaryngology O titis media (OM) is a middle-ear infection often caused by bacteria growth between the tympanic membrane (TM) and the inner ear. Middle-ear infections occur in approximately 75% of children by age 3 y, and ear infections are the most common childhood illness treated by pediatricians (1, 2). Young children often acquire ear infections after upper respiratory tract infections or allergic reactions to foods or environmental allergens. Adults account for almost 20% of the annual visits for OM (3). Characterization of middle-ear infections is currently based on symptoms, duration, otoscopic observation, and physical diagnosis. The most common type is acute OM (AOM), a rapid-onset infection with one or more symptoms including otalgia, fever, and irritability. In AOM, physicians often see an abnormal-appearing TM on pneumatic otoscopy, including bulging, opacity, effusion, and decreased mobility. Most cases of AOM clear in 1 or 2 w, and antibiotics are frequently used. Recurrent AOM and OM with effusion are considered chronic OM. These diseases often cause long-term or permanent ear damage, which is linked to hearing loss and speech delay in small children if inadequately treated. Most cases of chronic OM do not respond to antibiotic treatment (4, 5), and thus surg...

Full-Field Thickness Distribution of Human Tympanic Membrane Obtained with Optical Coherence Tomography

“…This combination of properties makes OCT a highly suitable imaging modality for in situ and in vivo applications in middle ear research. To date, the only reports of in vivo OCT measurements in middle ear research consist of preliminary tests that investigate its applicability in a clinical setup as a means to detect structural abnormalities in human TMs (Djalilian et al 2008;Nguyen et al 2012). These reports provide mainly qualitative descriptions of the measured TM thickness and include few quantitative measurements.…”

“…Recently, several successful feasibility studies on optical coherence tomography (OCT) in middle ear research, both ex vivo (Pitris et al 2001;Bibas et al 2004) and in vivo (Djalilian et al 2008;Just et al 2009;Nguyen et al 2012) have prompted us to conduct preliminary tests to measure full-field thickness variations of several rabbit and human TMs with OCT . Though successful, it was clear that additional hardware and software modifications to the measurement setup were required in order to measure full membranes.…”

In vivo imaging of middle-ear and inner-ear microstructures of a mouse guided by SD-OCT combined with a surgical microscope

“…In particular, OCT has become a commercialized product in ophthalmologic fields and is used to diagnose diseases missed by conventional equipment [5][6][7][8]. Recently, imaging studies in otolaryngology using OCT technology have been performed by various research groups all over the world [9][10][11][12][13][14]. In addition to anatomical studies using an OCT system, functional analyses such as the vibrations of middle-ear structures and the cochlear mechanics of the inner ear have been actively investigated by using optical Doppler tomography (ODT) and laser Doppler Vibrometry (LDV) [15][16][17].…”

Computational optical coherence tomography [Invited]

“…Since its introduction in the early 1990s, optical coherence tomography (OCT) has become an invaluable modality with widespread biomedical applications [1][2][3][4][5][6][7][8]. In particular, it is now a standard of clinical care in ophthalmology [9].…”