1. Articles in category: Otolaryngology

    1-24 of 272 1 2 3 4 ... 10 11 12 »
    1. Effect of tissue frozen on quantitative optical properties using optical coherence tomography

      Effect of tissue frozen on quantitative optical properties using optical coherence tomography

      The purpose is to demonstrate the optical charactering concerning nasopharyngeal tissue of pig by fresh sections and frozen correlating sections with optical coherence tomography (OCT). After being imaged on a fresh specimen, samples are then stored in low temperature refrigerators ( − 80 ° C −80°C ) for one year for the second OCT measurement. The OCT structure of the epithelium, lamina propria, and the basement membrane are still resolvable; the median scattering coefficients and anisotropy factors fitting from OCT images based on the multiple scattering effects for epithelium are 27.6    mm − 1 27.6  mm−1 [interquartile range (IQR) 23.6 ...

      Read Full Article
    2. Optical Coherence Tomography for Quantitative Diagnosis in Nasopharyngeal Carcinoma

      Optical Coherence Tomography for Quantitative Diagnosis in Nasopharyngeal Carcinoma

      We tried to quantitative diagnosis the intrinsic differences in the optical properties of nasopharyngeal carcinoma (NPC) from normal tissue by OCT. The scattering coefficients and anisotropies are extracted by fitting the average a-scan attenuation curves based on the multiple scatter effect. The median scattering coefficients of epithelium are 2.2 mm−1 (IQR 1.5 to 2.5 mm−1) for normal versus 3.8 mm−1 (IQR 2.0 to 3.3 mm−1) for cancer tissue; of lamina propria are 2.9 mm−1 (IQR 1.5 to 2.5 mm−1) for normal versus 1.3 mm ...

      Read Full Article
    3. ELHnet: a convolutional neural network for classifying cochlear endolymphatic hydrops imaged with optical coherence tomography

      ELHnet: a convolutional neural network for classifying cochlear endolymphatic hydrops imaged with optical coherence tomography

      Detection of endolymphatic hydrops is important for diagnosing Meniere’s disease, and can be performed non-invasively using optical coherence tomography (OCT) in animal models as well as potentially in the clinic. Here, we developed ELHnet, a convolutional neural network to classify endolymphatic hydrops in a mouse model using learned features from OCT images of mice cochleae. We trained ELHnet on 2159 training and validation images from 17 mice, using only the image pixels and observer-determined labels of endolymphatic hydrops as the inputs. We tested ELHnet on 37 images from 37 mice that were previously not used, and found that the ...

      Read Full Article
    4. University of Southern California Receives NIH Grant for Influence of Hair Bundle Properties on Cochlear Mechanics

      University of Southern California Receives NIH Grant for Influence of Hair Bundle Properties on Cochlear Mechanics

      University of Southern California Receives a 2017 NIH Grant for $37,696 Influence of Hair Bundle Properties on Cochlear Mechanics. The principal investigator is James Dewey. The program began in 2017 and ends in 2020. Below is a summary of the proposed work. Normal hearing depends on the delicate mechanotransduction apparatus of inner ear hair cells – the stereociliary hair bundle. Cochlear vibrations deflect the hair bundle, which converts mechanical stimulation to electrical signals via gating of mechanosensitive ion channels. Hair bundle transduction is critical for hearing, as it is required for afferent signaling by inner hair cells, and for activation ...

      Read Full Article
    5. University of Southern California Receives NIH Grant for Optical Coherence Tomography for 3D Measures of Cochlear Mechanics In Vivo.

      University of Southern California Receives NIH Grant for Optical Coherence Tomography for 3D Measures of Cochlear Mechanics In Vivo.

      University of Southern California Receives a 2017 NIH Grant $317,544 for Optical Coherence Tomography for 3D Measures of Cochlear Mechanics In Vivo. The principal investigator is John Oghalai. The program began in 2015 and ends in 2020. Below is a summary of the proposed work. The function of the cochlea is to transduce complex sound pressure waves into electrical signals. Organ of Corti vibration is based upon a complex interplay between passive mechanical structures and active OHC- based processes. While laser Doppler vibrometry has added tremendously to our understanding of cochlear physiology, this technique is limited. Only motion from ...

      Read Full Article
    6. Recent Developments in FullField Thickness Measurements of the Human Eardrum

      Recent Developments in FullField Thickness Measurements of the Human Eardrum

      Recently, we published several full-field human tympanic membrane data sets that were obtained using a modified high-resolution optical coherence tomography setup. In this short communication letter, we provide an overview of the active research fields in which these data have been used or in which human tympanic membrane thickness measurements play an instrumental role. These applications include finite element modeling of the middle ear system, medical diagnosis of middle ear pathology and the design of tympanic membrane grafts.

      Read Full Article
    7. UIUC Receives a NIH Grant for Partnership for Primary Care Imaging of the Ear

      UIUC Receives a NIH Grant for Partnership for Primary Care Imaging of the Ear

      University of Illinois at Urbana-Champaign Receives a 2017 NIH Grant for $454,301 for Partnership for Primary Care Imaging of the Ear. The principal investigator is Stepen Boppart. The program began in 2011 and ends in 2019. Below is a summary of the proposed work. Biofilms in the human middle-ear are known to be directly associated with chronic otitis media (OM), and the bacteria that reside within these protective biofilms are likely responsible for contributing to the persistence and re-seeding of the infection despite repeated doses of antibiotics. While prior sampling of human middle-ear biofilms was performed invasively during a ...

      Read Full Article
    8. Motion of intracochlear structures measured with a commercial optical coherence tomography (OCT) system

      Motion of intracochlear structures measured with a commercial optical coherence tomography (OCT) system

      Most knowledge of the motion of cochlear structures has been limited to measurements through the round window at the extreme base of the cochlea or through a hole made in the cochlear capsule, which can modify cochlear mechanics. Optical coherence tomography (OCT) provides the ability to measure shape or motion of structures through a thin layer of tissue or bone. The motion of cochlear structures has been measured in the mouse cochlear apex without making an opening into the cochlea, using a custom OCT system. Here we describe intracochlear vibrometry using a commercial OCT system. Specimens were prepared by opening ...

      Read Full Article
      Mentions: Thorlabs
    9. Integrating optical coherence tomography with laryngeal videostroboscopy

      Integrating optical coherence tomography with laryngeal videostroboscopy

      During clinical voice assessment, laryngologists and speech-language pathologists rely heavily on laryngeal endoscopy with videostroboscopy to evaluate pathology and dysfunction of the vocal folds. The cost effectiveness, ease of use, and synchronized audio and visual feedback provided by videostroboscopic assessment serve to maintain its predominant clinical role in laryngeal imaging. However, significant drawbacks include only two-dimensional spatial imaging and the lack of subsurface morphological information. A novel endoscope will be presented that integrates optical coherence tomography that is spatially and temporally co-registered with laryngeal videoendoscopic technology through a common path probe. Optical coherence tomography is a non-contact, micron-resolution imaging technology ...

      Read Full Article
    10. Stanford University Receives NIH Grant for Cochlear Mechanics in the Mouse

      Stanford University Receives NIH Grant for Cochlear Mechanics in the Mouse

      Stanford University Receives a 2017 NIH Grant for $307,982 for Cochlear Mechanics in the Mouse. The principal investigator is John Oghalai. The program began in 2015 and ends in 2020. 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 ...

      Read Full Article
    11. Stanford Receives NIH Grant for Optical Coherence Tomography for 3D Measures of Cochlear Mechanics In Vivo

      Stanford Receives NIH Grant for Optical Coherence Tomography for 3D Measures of Cochlear Mechanics In Vivo

      Stanford University Receives a 2017 NIH Grant for $364,249 for Optical Coherence Tomography for 3D Measures of Cochlear Mechanics In Vivo. The principal investigator is John Oghalai. The program began in 2015 and ends in 2020. Below is a summary of the proposed work. The function of the cochlea is to transduce complex sound pressure waves into electrical signals. Organ of Corti vibration is based upon a complex interplay between passive mechanical structures and active OHC- based processes. While laser Doppler vibrometry has added tremendously to our understanding of cochlear physiology, this technique is limited. Only motion from one ...

      Read Full Article
    12. Stanford Receives NIH Grant f for Influence of Hair Bundle Properties on Cochlear Mechanics

      Stanford Receives NIH Grant f for Influence of Hair Bundle Properties on Cochlear Mechanics

      Stanford University Receives a 2017 NIH Grant for $56,694 for Influence of Hair Bundle Properties on Cochlear Mechanics. The principal investigator is James Dewey. The program began in 20-17 and ends in 2020. Below is a summary of the proposed work. Normal hearing depends on the delicate mechanotransduction apparatus of inner ear hair cells – the stereociliary hair bundle. Cochlear vibrations deflect the hair bundle, which converts mechanical stimulation to electrical signals via gating of mechanosensitive ion channels. Hair bundle transduction is critical for hearing, as it is required for afferent signaling by inner hair cells, and for activation of ...

      Read Full Article
    13. In vivo 3D imaging of the human tympanic membrane using a wide-field diagonal-scanning optical coherence tomography probe

      In vivo 3D imaging of the human tympanic membrane using a wide-field diagonal-scanning optical coherence tomography probe

      A wide-field optical coherence tomography (OCT) probe was developed that adapts a diagonal-scanning scheme for three-dimensional (3D) in vivo imaging of the human tympanic membrane. The probe consists of a relay lens to enhance the lateral scanning range up to 7 mm. Motion artifacts that occur with the use of handheld probes were found to be decreased owing to the diagonal-scanning pattern, which crosses the center of the sample to facilitate entire 3D scans. 3D images could be constructed from a small number of two-dimensional OCT images acquired using the diagonal-scanning technique. To demonstrate the usefulness and performance of the ...

      Read Full Article
    14. Seeing, understanding how we hear

      Seeing, understanding how we hear

      Cutting-edge technology is giving QEII Health Sciences Centre clinicians a close up look at the inner workings of the human ear. “We are the only place in the world that has managed to measure ear vibrations in humans. We are definitely the furthest ahead,” says Dr. Manohar Bance, QEII ear surgeon. When it comes to middle ear dysfunctions, surgeries to cut open the tympanic membrane, or eardrum, are frequently conducted on patients in attempt to identify problems and restore vibrating connections. Anything that can block the passage of vibrations will lead to hearing loss. Fluid is one thing, which is ...

      Read Full Article
    15. Intraoperative assessment of laryngeal pathologies with optical coherence tomography integrated into a surgical microscope

      Intraoperative assessment of laryngeal pathologies with optical coherence tomography integrated into a surgical microscope

      Objective Endoscopic examination followed by tissue biopsy is the gold standard in the evaluation of lesions of the upper aerodigestive tract. However, it can be difficult to distinguish between healthy mucosa, dysplasia, and invasive carcinoma. Optical coherence tomography (OCT) is a non-invasive technique which acquires high-resolution, cross-sectional images of tissue in vivo . Integrated into a surgical microscope, it allows the intraoperative evaluation of lesions simultaneously with microscopic visualization. Study Design In a prospective case series, we evaluated the use of OCT integrated into a surgical microscope during microlaryngoscopy to help differentiating various laryngeal pathologies. Methods 33 patients with laryngeal pathologies ...

      Read Full Article
    16. Extratympanic imaging of middle and inner ear structures of mouse and rat using optical coherence tomography

      Extratympanic imaging of middle and inner ear structures of mouse and rat using optical coherence tomography

      ackground and Objective: Noninvasive middle and inner ear imaging using optical coherence tomography (OCT) presents some unique challenges for real-time, clinical use in animals and humans. The goal of this study was to investigate whether OCT provides information about the middle and inner ear microstructures by examining extratympanic structures. Materials and Methods: Five mice and rats were included in the experiment, and the swept-source OCT system was tested to identify the middle and inner ear microstructures and to measure the length or thickness of various structures. Results: It was possible to see middle ear structures through the tympanic membrane with ...

      Read Full Article
    17. Signal competition in optical coherence tomography and its relevance for cochlear vibrometry

      Signal competition in optical coherence tomography and its relevance for cochlear vibrometry

      The usual technique for measuring vibration within the cochlear partition is heterodyne interferometry. Recently, spectral domain phase microscopy (SDPM) was introduced and offers improvements over standard heterodyneinterferometry. In particular, it has a penetration depth of several mm due to working in the infrared range, has narrow and steep optical sectioning due to using a wideband light source, and is able to measure from several cochlear layers simultaneously. However, SDPM is susceptible to systematic error due to “phase leakage,” in which the signal from one layer competes with the signal from other layers. Here, phase leakage is explored in vibration measurements ...

      Read Full Article
      Mentions: Christine Hendon
    18. Low-cost hand-held probe for depth-resolved low-coherence interferometry

      Low-cost hand-held probe for depth-resolved low-coherence interferometry

      We report on the development of a low-cost hand-held low-coherence interferometric imaging system based on the principle of linear optical coherence tomography (Linear OCT), a technique which was first proposed in the early 2000s as a simpler alternative to the conventional time-domain and Fourier-domain OCT. A bench-top implementation of the proposed technique is first presented and validated. The axial resolution, SNR, and sensitivity roll-of of the system was estimated to be 5.2 μm and 80 dB, and 3.7 dB over a depth of 0.15 mm, respectively. After validating the bench-top system, two hand-held probe implementations for contact-based ...

      Read Full Article
    19. Experimental Visualization of Labyrinthine Structure with Optical Coherence Tomography

      Experimental Visualization of Labyrinthine Structure with Optical Coherence Tomography

      Introduction: Visualization of inner ear structures is a valuable strategy for researchers and clinicians working on hearing pathologies. Optical coherence tomography (OCT) is a high-resolution imaging technology which may be used for the visualization of tissues. In this experimental study we aimed to evaluate inner ear anatomy in well-prepared human labyrinthine bones. Materials and Methods: Three fresh human explanted temporal bones were trimmed, chemically decalcified with ethylenediaminetetraacetic acid (EDTA), and mechanically drilled under visual control using OCT in order to reveal the remaining bone shell. After confirming decalcification with a computed tomography (CT) scan, the samples were scanned with OCT ...

      Read Full Article
    20. Mesenchymal stem cell-laden hybrid scaffold for regenerating subacute tympanic membrane perforation

      Mesenchymal stem cell-laden hybrid scaffold for regenerating subacute tympanic membrane perforation

      ympanic membrane (TM) perforation is one of the most common otology complications. To date, there has not been reported TM regeneration using bioprinted scaffold. The purpose of this study was to evaluate the efficacy and feasibility of bioprinted polycaprolactone/collagen/alginate-mesenchymal stem cell (PCAMSC) scaffolds for the regeneration of subacute TM perforation. Sprague-Dawley rats were used in an animal model of subacute TM perforation. In the experimental group (n = 7), bioprinted 3D PCAMSC scaffold was placed on the perforation. The control group (n = 7) were treated with polycaprolactone/collagen/alginate (PCA) scaffold. Healing time, acoustic-mechanical properties, and morphological analysis were ...

      Read Full Article
      Mentions: Byeong Ha Lee
    21. Dynamic nanomechanical analysis of the vocal fold structure in excised larynges

      Dynamic nanomechanical analysis of the vocal fold structure in excised larynges

      Objectives/Hypothesis Quantification of clinical outcomes after vocal fold (VF) interventions is challenging with current technology. High-speed digital imaging and optical coherence tomography (OCT) of excised larynges assess intact laryngeal function, but do not provide critical biomechanical information. We developed a protocol to quantify tissue properties in intact, excised VFs using dynamic nanomechanical analysis (nano-DMA) to obtain precise biomechanical properties in the micrometer scale. Study Design Experimental animal study. Methods Three pig larynges were bisected in the sagittal plane, maintaining an intact anterior commissure, and subjected to nano-DMA at nine locations with a 250-μm flat-tip punch and frequency sweep ...

      Read Full Article
    22. Human ex-vivo oral tissue imaging using spectral domain polarization sensitive optical coherence tomography

      Human ex-vivo oral tissue imaging using spectral domain polarization sensitive optical coherence tomography

      We report the use of spectral domain polarization sensitive optical coherence tomography for ex-vivo imaging of human oral mandibular tissue samples. Our results show that compared to the changes observed in the epithelium thickness and the decay constant of A-scan intensity profile, a much larger degree of change was observed in the phase retardation for tissue sites progressing from normal to the malignant state. These results suggest that monitoring of tissue retardance can help in better differentiation of normal and cancerous oral tissue sites.

      Read Full Article
    23. Doppler optical coherence tomography as a promising tool for detecting fluid in the human middle ear

      Doppler optical coherence tomography as a promising tool for detecting fluid in the human middle ear

      The treatment of otitis media requires classifying the effusion in the tympanic cavity for choosing appropriate therapeutic strategies. Otoscopic examination of the middle ear depends on the expertise of the physician and is often hampered in case of inflammatory alterations of the tympanic membrane. In otologic research, optical coherence tomography is an innovative non-invasive imaging technique utilized for visualizing the tympanic membrane. This ex vivo study presents the possibility of OCT and Doppler-OCT for the detection of effusions in the tympanic cavity. Structural OCT imaging allows the direct visualization of scattering fluids behind the tympanic membrane. In addition, the measurement ...

      Read Full Article
    1-24 of 272 1 2 3 4 ... 10 11 12 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Popular Articles

  3. Organizations in the News

    1. (2 articles) University of Southern California
    2. (1 articles) Stanford University
    3. (1 articles) National Institutes of Health
    4. (1 articles) Texas A&M University
  4. People in the News

    1. (1 articles) John S. Oghalai
    2. (1 articles) Brian E. Applegate