Immediate and delayed cochlear neuropathy after noise exposure in pubescent mice.

Moderate acoustic overexposure in adult rodents is known to cause acute loss of synapses on sensory inner hair cells (IHCs) and delayed degeneration of the auditory nerve, despite the completely reversible temporary threshold shift (TTS) and morphologically intact hair cells. Our objective was to determine whether a cochlear synaptopathy followed by neuropathy occurs after noise exposure in pubescence, and to define neuropathic versus non-neuropathic noise levels for pubescent mice. While exposing 6 week old CBA/CaJ mice to 8-16 kHz bandpass noise for 2 hrs, we defined 97 dB sound pressure level (SPL) as the threshold for this particular type of neuropathic exposure associated with TTS, and 94 dB SPL as the highest non-neuropathic noise level associated with TTS.

Loss of osteoprotegerin expression in the inner ear causes degeneration of the cochlear nerve and sensorineural hearing loss.

Osteoprotegerin (OPG) is a key regulator of bone remodeling. Mutations and variations in the OPG gene cause many human diseases that are characterized by not only skeletal abnormalities but also poorly understood hearing loss: Paget's disease, osteoporosis, and celiac disease. To gain insight into the mechanisms of hearing loss in OPG deficiency, we studied OPG knockout (Opg(-/-)) mice.

Phonosurgery of vocal fold polyps, cysts and nodules is beneficial.

Introduction: This study reports our experience with microscopic phonosurgery (PS) of benign lesions of the vocal folds.

Material And Methods: During the five-year period from 2003 to 2007, a total of 97 patients had PS for vocal fold polyps (n = 63), vocal fold cysts (n = 17), vocal fold nodules (n = 12) or vocal fold oedema (n = 5). Their average age was 41 years; 62% were women and 69% were smokers.