David Lee, M.D., Washington University in St. Louis; Optical Coherence Tomography of Inner Ear Structures: Using Novel Imaging Technology to Investigate Meniere's Disease and Sudden Sensorineural Hearing Loss
University of Southern California Received a 2022 NIH Grant for $516,925 for Mechanisms of cochlear synaptopathy after noise or blast trauma. The principal investigator is John Oghalai. Below is a summary of the proposed work. About 15% of Americans have hearing loss due to noise exposure. The classical explanation is trauma to the cochlear hair cells. An additional mechanism of noise-induced hearing loss is cochlear synaptopathy. There are no effective treatments used clinically to prevent hearing loss via either mechanism after traumatic noise exposure. Recently, we identified that endolymphatic hydrops occurs after blast or noise trauma, and that endolymphatic ...
Massachusetts Eye and Ear Infirmary Received a 2022 NIH Grant for $488,619 for Measuring and Modeling the Cochlear Motions that Drive the Inner and Outer Hair Cells and Produce Otoacoustic Emissions. The principal investigator is Sunil Puria. Below is a summary of the proposed work. Our knowledge of cochlear mechanics is currently undergoing a revolution. While the basilar membrane (BM) has long been considered the principal structure in cochlear motion, new techniques such as optical coherence tomography (OCT) have instead revealed not only that the reticular lamina (RL) moves in a different pattern from the BM, but that it ...
Medical College of Wisconsin received a 2022 NIH Grant for $576,383 for Otitis Media Diagnosis and Treatment. The principal investigator is Joseph Kerchner. Below is a summary of the proposed work. Otitis media (OM) is the most common diagnosis in pediatric patients seen for illness in the United States (1,2), affects 90% of all children (3,4) and is the most common indication for antimicrobial therapy and surgery (5) in young children. Despite many attempts to improve diagnosis, treatment, and prevention, OM continues its highly prevalent impact on children and substantial ongoing morbidity (1,3,6-30). OM continues ...
University of Southern California received a 2022 NIH Grant for $586,520 for Optical Imaging Technologies to Identity Residual Cholesteatoma and Improve Ossiculplasty Outcomes. The principal investigator is Brian Applegate. Below is a summary of the proposed work. There are a number of diseases and conditions in the middle ear that cause hearing loss in both children and adults. In children it is particularly important to expedite interventions to restore hearing since it negatively impacts language development and academic performance. An example is cholesteatoma, a benign lesion due to abnormal skin growth in the middle ear which facilitates erosion of ...
Vibrations of the tympanic membrane (TM) play a key role in the diagnosis of the middle ear in hearing research. The thickness is one of the factors that determines performance analysis of the TM and plays an important role in forming vibration patterns. When the thickness of TM is changed for various reasons, the vibration pattern is also changed, which interferes with sound transmission. The previously reported studies of measuring TM obtained the response of the entire or at a single point to understand the characteristics of the TM, which is limited to providing detailed information for the region of ...
Several studies have shown that in recent years incidence of acute otitis media (AOM) has declined worldwide. However, related medical, social, and economic problems for patients, their families, and society remain very high. Better knowledge of potential risk factors for AOM development and more effective preventive interventions, particularly in AOM-prone children, can further reduce disease incidence. However, a more accurate AOM diagnosis seems essential to achieve this goal. Diagnostic uncertainty is common, and to avoid risks related to a disease caused mainly by bacteria, several children without AOM are treated with antibiotics and followed as true AOM cases. The main ...
PhotoniCare, Inc.—a company revolutionizing frontline care with the OtoSight Middle Ear Scope that uses OCT technology to increase the objective accuracy of fluid assessment in the middle ear—announced that they have successfully completed their ISO 13485:2016 certification today. ISO 13485:2016 is an internationally recognized quality standard that specifies requirements for a quality management system used by an organization demonstrating its ability to provide medical devices and related services that consistently meet strict regulatory and customer requirements. The Quality Management System PhotoniCare utilizes to design, manufacture, and service OtoSight Middle Ear Scopes has officially been audited and ...
It is a common belief that the mammalian cochlea achieves its exquisite sensitivity, frequency selectivity, and dynamic range through an outer hair cell-based active process, or cochlear amplification. As a sound-induced traveling wave propagates from the cochlear base toward the apex, outer hair cells at a narrow region amplify the low level sound-induced vibration through a local feedback mechanism. This widely accepted theory has been tested by measuring sound-induced sub-nanometer vibrations within the organ of Corti in the sensitive living cochleae using heterodyne low-coherence interferometry and optical coherence tomography. The aim of this short review is to summarize experimental findings ...
Objectives/hypothesis: To establish the utility of anatomic optical coherence tomography (aOCT) in evaluating internal nasal valve (INV). Study design: Anatomic specimen imaging study. Methods: Fresh-harvested human specimen heads were evaluated using both computed tomography (CT) imaging as well as using aOCT. Scans were performed at three time points: 1) After septoplasty for cartilage harvest, 2) after placement of butterfly graft (BFG), and 3) after placement of bilateral spreader grafts (SG). Imaging data were then converted into 3D models of the nasal airway. CT- and aOCT-generated models were compared by both static volumetric analysis and computational fluid dynamics (CFD) to ...
Intra organ of Corti (OC) vibrations differ from those measured at the basilar membrane (BM), with higher amplitudes and a wide-band nonlinearity extending well below a region’s best frequency. The vibrations are boosted by the cochlear amplifier, the active processes within the mammalian hearing organ, and are thus sensitive to metabolic or pharmacological manipulation. We introduced salicylate, a known blocker of outer hair cell (OHC) based electromotility, into the perilymphatic space by applying sodium salicylate onto the round window membrane. Vibration patterns of an area of the OC were mapped with phase sensitive optical coherence tomography before and after ...
After acoustic trauma, there can be loss of synaptic connections between inner hair cells and auditory neurons in the cochlea, which may lead to hearing abnormalities including speech-in-noise difficulties, tinnitus, and hyperacusis. We have previously studied mice with blast-induced cochlear synaptopathy and found that they also developed a build-up of endolymph, termed endolymphatic hydrops. In this study, we used optical coherence tomography to measure endolymph volume in live CBA/CaJ mice exposed to various noise intensities. We quantified the number of synaptic ribbons and postsynaptic densities under the inner hair cells 1 week after noise exposure to determine if they ...
Exposure to loud noise, such as a firecracker or an ear-splitting concert, is the most common preventable cause of hearing loss. Research suggests that 12% or more of the world population is at risk for noise-induced loss of hearing. Loud sounds can cause a loss of auditory nerve cells in the inner ear, which are responsible for sending acoustic information to the brain, resulting in hearing difficulty. However, the mechanism behind this hearing loss is not fully understood.
The aim of this study is to understand the diagnostic applications for this imaging technology and identify particular disorders to target for future clinical investigations. Images obtained with the Ossiview device will be correlated to other standard of care (SoC) testing including microscopic otoscopy, CT scans, MRIs, audiologic testing results, and surgical and pathology reports.
This free, live event will take place on October 6 th, 10 EDT (4 PM CET) and will include an interactive Q&A session. For information and to register please visit this link. After the event a recorded version will be available at www.thorlabs.com/webinars . Abstract: Drs. Elizabeth Olson and Elliott Strimbu from Columbia University will highlight Phase Sensitive Spectral Domain Optical Coherence Tomography as it relates to nanoscale vibrometry. They will cover in detail the performance parameters of a Thorlabs Telesto for nanoscale displacement measurements in the cochlea and leverage their years of experience in the field ...
Sensorineural hearing loss (SNHL) is one of the most profound public health concerns of the modern era, affecting 466 million people today, and projected to affect 900 million by the year 2050. Advances in both diagnostics and therapeutics for SNHL have been impeded by the human cochlea's inaccessibility for in vivo imaging, resulting from its extremely small size, convoluted coiled configuration, fragility, and deep encasement in dense bone. Here, we develop and demonstrate the ability of a sub-millimeter-diameter, flexible endoscopic probe interfaced with a micro-optical coherence tomography (μOCT) imaging system to enable micron-scale imaging of the inner ear's ...
Significance: The human vocal fold (VF) oscillates in multiple vectors and consists of distinct layers with varying viscoelastic properties that contribute to the mucosal wave. Office-based and operative laryngeal endoscopy are limited to diagnostic evaluation of the VF epithelial surface only and are restricted to axial-plane characterization of the horizontal mucosal wave. As such, understanding of the biomechanics of human VF motion remains limited. Aim: Optical coherence tomography (OCT) is a micrometer-resolution, high-speed endoscopic imaging modality which acquires cross-sectional images of tissue. Our study aimed to leverage OCT technology and develop quantitative methods for analyzing the anatomy and kinematics of ...
It’s a perennial pediatric problem: more than 80 percent of children will have at least one ear infection by their third birthday. Beyond the pain and irritability that an ear infection can bring — for both children and their parents alike — untreated or recurring infections can result in hearing loss, which may affect the development of speech and language skills. With nearly 20 million estimated cases of acute middle ear infections each year in the United States, the annual cost associated with this condition is estimated to exceed $4 billion. “It’s a universally understood misery, this issue of chronic ...
Methods and apparatus for identifying microbiological constituents in the middle ear. A spectrometer receives Raman-scattered light from the region of the tympanic membrane and resolves spectral features of the Raman-scattered light. A processor receives the interferometry signal and the Raman signal, and generates a Raman spectrum of the tympanic membrane and material adjacent thereto. In some embodiments of the invention, low-coherence light and substantially monochromatic excitation light are directed onto a tympanic membrane of the ear of a person via an otoscopic tip that abuts the ear canal. An interferometer combines scattered low-coherence light from the ear tissue with a ...
We describe an optical coherence tomography and vibrometry system designed for portable hand-held usage in the otology clinic on awake patients. The system provides clinically relevant point-of-care morphological imaging with 14-44 µm resolution and functional vibratory measures with sub-nanometer sensitivity. We evaluated various new approaches for extracting functional information including a multi-tone stimulus, a continuous chirp stimulus, and alternating air and bone stimulus. We also explored the vibratory response over an area of the tympanic membrane (TM) and generated TM thickness maps. Our results suggest that the system can provide real-time in vivo imaging and vibrometry of the ear and ...
Oregon Health & Science University Receives a 2021 NIH Grant for $593,243 for The Mechanical and Ionic Roles of Cochlear fluids in Hearing and Hearing Loss. The principal investigator is Alfred Nuttal. Below is a summary of the proposed work. A goal of the cochlear physiology laboratory is to understand how the components of the organ of Corti tune the sound induced vibration of the organ of Corti. A process known as cochlear amplification (CA), now the subject of intense work around the world, has critical components not yet studied. Two questions of broad interest that this proposal address are ...
University of Illinois at Urbana-Champaign Receives a 2021 NIH Grant for $653,667 for Integration of Raman Spectroscopy and Optical Coherence Tomography (RS-OCT) for In-Vivo Identification of Bacterial Otitis Media. The principal investigator is Yan Li. Below is a summary of the proposed work. Otitis media (middle ear infection) is a highly prevalent disease, especially in young children. It has been documented that more than 75% of children will have at least one episode of otitis media (OM) by age 3, and many children will have recurrent or chronic OM. In most cases, diagnosis of an ear infection is performed ...
University of Southern California Receives a 2021 NIH Grant for $625,265 for Cochlear Mechanics in the Mouse. The principal investigator is John Oghalai. Below is a summary of the proposed work. Sound pressure produces force across the mammalian cochlear partition, ultimately creating a vibratory traveling wave that propagates longitudinally up the cochlear duct. The key feature distinguishing this process from the non-mammalian cochlea is amplification, whereby forces produced by thousands of outer hair cells (OHCs) sharpen and amplify the traveling wave. Our overarching objective is to understand how the complex biomechanics of the 3D multi-cellular and acellular arrangement that ...
Studying the in-vivo mechanical and electrophysiological cochlear responses in several species helps us to have a comprehensive view of the sensitivity and frequency selectivity of the cochlea. Different species might use different mechanisms to achieve the sharp frequency-place map. The outer hair cells (OHC) play an important role in mediating frequency tuning. In the present work, we measured the OHC-generated local cochlear microphonic (LCM) and the motion of different layers in the organ of Corti using optical coherence tomography (OCT) in the first turn of the cochlea in guinea pig. In the best frequency (BF) band, our observations were similar ...
