the-mouse-round-window-approach-for-ototoxic-agent-delivery-rapid

The Mouse Round-window Approach for Ototoxic Agent Delivery: A Rapid and Reliable Technique for Inducing Cochlear Cell Degeneration

Investigators have utilized a wide array of animal models and investigative techniques to study the mammalian auditory system. Much of the basic research ...

Medical University of South Carolina

Age-related hearing loss (presbyacusis) is the most common type of hearing impairment. One of the most consistent pathological changes seen in presbyacusis is the loss of spiral ganglion neurons (SGNs). Defining the cellular and molecular basis of SGN degeneration in the human inner ear is critical to gaining a better understanding of the pathophysiology of presbyacusis. However, information on age-related cellular and molecular alterations in the human spiral ganglion remains scant, owing to the very limited availably of human specimens suitable for high resolution morphological and molecular analysis. This study aimed at defining age-related alterations in the auditory nerve in human temporal bones and determining if immunostaining for myelin basic protein (MBP) can be used as an alternative approach to electron microscopy for evaluating myelin degeneration. For comparative purposes, we evaluated ultrastructural alternations and changes in MBP immunostaining in aging CBA/CaJ mice. We then examined 13 temporal bones from 10 human donors, including 4 adults aged 38-46 years (middle-aged group) and 6 adults aged 63-91 years (older group). Similar to the mouse, intense immunostaining of MBP was present throughout the auditory nerve of the middle-aged human donors. Significant declines in MBP immunoreactivity and losses of MBP(+) auditory nerve fibers were observed in the spiral ganglia of both the older human and aged mouse ears. This study demonstrates that immunostaining for MBP in combination with confocal microscopy provides a sensitive, reliable, and efficient method for assessing alterations of myelin sheaths in the auditory nerve. The results also suggest that myelin degeneration may play a critical role in the SGN loss and the subsequent decline of the auditory nerve function in presbyacusis.

Age-related changes of myelin basic protein in mouse and human auditory nerve.

Identify cells supporting cochlear lateral wall regeneration.

Heptanol application to the mouse round window: a model for studying cochlear lateral wall regeneration.

(1) To describe a validated algorithm for measuring tegmen thickness on computed tomography scans. (2) To compare the tegmen thickness in 3 groups: patients with spontaneous cerebrospinal fluid (CSF) leaks, obese controls, and nonobese controls.

Novel radiographic measurement algorithm demonstrating a link between obesity and lateral skull base attenuation.

This article aims to review relevant implications of obesity and associated comorbid conditions for the otology and neurotology surgical subspecialties.

Obesity related complications in surgery.

Length of stay is a marker of quality and efficiency of health care delivery. The objective of this study was to identify preoperative, intraoperative, and postoperative variables that impact length of stay after lateral skull base surgery. Methods/Procedures: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) databases from 2009-2012 were analyzed, and patients undergoing elective lateral skull base surgery for benign lesions of cranial nerves were identified. The primary outcome measure of interest was length of hospital stay. Protracted length of stay was defined as ≥75th percentile of length of stay for all patients. The impact of demographic factors, intraoperative variables, and postoperative complications on length of stay was assessed.

The Relation between Obesity and Hospital Length of Stay after Elective Lateral Skull Base Surgery: An Analysis of the American College of Surgeons National Surgical Quality Improvement Program.

1) Stratify malignant otitis externa into severe and nonsevere disease categories. 2) Predict treatment courses and outcomes based on this stratification.

Article	Year
Age-related changes of myelin basic protein in mouse and human auditory nerve. PloS one\| PubMed ID: 22496821	2012
Heptanol application to the mouse round window: a model for studying cochlear lateral wall regeneration. Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery\| PubMed ID: 24436465	2014
Novel radiographic measurement algorithm demonstrating a link between obesity and lateral skull base attenuation. Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery\| PubMed ID: 25450407	2015
Obesity related complications in surgery. Current opinion in otolaryngology & head and neck surgery\| PubMed ID: 26339964	2015
The Relation between Obesity and Hospital Length of Stay after Elective Lateral Skull Base Surgery: An Analysis of the American College of Surgeons National Surgical Quality Improvement Prog... ORL; journal for oto-rhino-laryngology and its related specialties\| PubMed ID: 26360829	2015
Malignant Otitis Externa: A Novel Stratification Protocol for Predicting Treatment Outcomes. Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology\| PubMed ID: 26375971	2015

Shawn M. Stevens

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