MRI scanning generates high levels of acoustic noise that cannot only pose a safety hazard, but also impair communication between staff and patient. In this article we present active noise control (ANC) techniques that introduce antiphase noise to destructively interfere with the MRI noise and with the aim of producing a zone of quiet around the patient's ears. Using noise recorded from a 1.0 Tesla midfield MR scanner the acoustic noise generated by three standard MR imaging sequences was replayed to a real time two channel ANC system. The results obtained show a useful attenuation of low-frequency periodic acoustic noise components. Therefore, in combination with standard passive ear protection, this suggests that MR generated acoustic noise can be effectively attenuated at both low and high frequencies leading to improved patient comfort.
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http://dx.doi.org/10.1016/s0730-725x(96)00337-2 | DOI Listing |
Eur Arch Otorhinolaryngol
January 2025
Motion Sickness and Human Performance Laboratory, The Israel Naval Medical Institute, IDF Medical Corps, Haifa, Israel.
Purpose: Acute acoustic trauma (AAT) is a sudden sensorineural hearing loss (SNHL) due to exposure to high intensity impulse noise. There are no acceptable treatment guidelines, although several studies showed steroids could be effective in restoring hearing levels. A recent report suggested that steroids combined with hyperbaric oxygen therapy (HBOT) are a superior regiment for AAT.
View Article and Find Full Text PDFLife (Basel)
December 2024
Neuromodulation Center and Center for Clinical Research Learning, Spaulding Rehabilitation Hospital, Massachusetts General Hospital, Harvard Medical School, 1575 Cambridge Street, Cambridge, MA 02115, USA.
Background: This study aimed to explore the potential associations between voice metrics of patients with PD and their motor symptoms.
Methods: Motor and vocal data including the Unified Parkinson's Disease Rating Scale part III (UPDRS-III), Harmonic-Noise Ratio (HNR), jitter, shimmer, and smoothed cepstral peak prominence (CPPS) were analyzed through exploratory correlations followed by univariate linear regression analyses. We employed these four voice metrics as independent variables and the total and sub-scores of the UPDRS-III as dependent variables.
Micromachines (Basel)
January 2025
Key Laboratory of Instrumentation Science and Dynamic Measurement Ministry of Education, North University of China, Taiyuan 030051, China.
A Hz level narrow linewidth all-optical microwave oscillator based on the torsional radial acoustic modes (TR) of a single-mode fiber (SMF) is proposed and validated. The all-optical microwave oscillator consists of a 20 km SMF main ring cavity and a 5 km SMF sub ring cavity. The main ring cavity provides forward stimulated Brillouin scattering gain and utilizes a nonlinear polarization rotation effect to achieve TR mode locking.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Otolaryngology-Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America.
Objective: What we hear may influence postural control, particularly in people with vestibular hypofunction. Would hearing a moving subway destabilize people similarly to seeing the train move? We investigated how people with unilateral vestibular hypofunction and healthy controls incorporated broadband and real-recorded sounds with visual load for balance in an immersive contextual scene.
Design: Participants stood on foam placed on a force-platform, wore the HTC Vive headset, and observed an immersive subway environment.
Proc Natl Acad Sci U S A
January 2025
Department of Neurobiology, Harvard Medical School, Boston, MA 02115.
The sense of hearing originates in the cochlea, which detects sounds across dynamic sensory environments. Like other peripheral organs, the cochlea is subjected to environmental insults, including loud, damage-inducing sounds. In response to internal and external stimuli, the central nervous system directly modulates cochlear function through olivocochlear neurons (OCNs), which are located in the brainstem and innervate the cochlear sensory epithelium.
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