Debra G. Weinberger

A bovine acellular scaffold for vocal fold reconstruction in a rat model

With a rat model of vocal fold injury, this study examined the in vivo host response to an acellular xenogeneic scaffold derived from the bovine vocal fold lamina propria, and the potential of the scaffold for constructive tissue remodeling. Bilateral wounds were created in the posterior vocal folds of 20 rats, and bovine acellular scaffolds were implanted into the wounds unilaterally, with the contralateral vocal folds as control. The rats were humanely sacrificed after 3 days, 7 days, 1 month, and 3 months, and the coronal sections of their larynges were examined histologically. Expressions of key matrix proteins including collagen I, collagen III, elastin, fibronectin, hyaluronic acid, and glycosaminoglycans (GAGs) were quantified with digital image analysis. Significant infiltration of host inflammatory cells and host fibroblasts in the scaffold implant was observed in the acute stage of wound repair (3 days and 7 days postsurgery). The mean relative densities of collagen I, collagen III, and GAGs in the implanted vocal folds were significantly higher than those in the control after 3 days, followed by gradual decreases over 3 months. Histological results showed that the scaffolds were apparently degraded by 3 months, with no fibrotic tissue formation or calcification. These preliminary findings suggested that the bovine acellular scaffold could be a potential xenograft for vocal fold regeneration.

Surgical anatomy and variations of the onodi cell

Onodi cells are posterior ethmoid cells superolateral to the sphenoid sinus that is intimately associated with the optic nerve. Embryologically, they are derived from ethmoid cells that have undergone dedifferentiation. The anatomic relationship of the Onodi cell to the optic nerve and the internal carotid artery has not been clearly documented in the literature. Forty-four sagittal sections of cadaver heads and 83 CT scans of the sinuses were examined. Case studies of three patients with Onodi cell sinusitis are presented. Two patients underwent endoscopic sinus surgery, and the other chose conservative medical management. The cadaver specimens revealed Onodi cells in 14% (6/44 sections). They were located lateral, superior, or superolateral to the sphenoid sinus. These relationships were further delineated by studying CT scans of the sinuses of 76 patients. Six patients (8%) had Onodi cells. Four of them had a dehiscence of the optic nerve adjacent to the Onodi cell. Twelve patients (16%) demonstrated a dehiscence of the internal carotid artery. These findings have important implications in endoscopic sinus surgery. The anatomic variability of the posterior ethmoids, sphenoid sinus, internal carotid artery, and optic nerve makes this surgical approach particularly challenging.

Hypopharyngeal Surgery in Obstructive Sleep Apnea Practice Patterns, Perceptions, and Attitudes

Objective To characterize factors that surgeons perceive as affecting selection of procedures designed to treat hypopharyngeal obstruction in adults with obstructive sleep apnea (OSA) and to compare those factors among 2 groups of American Academy of Otolaryngology—Head and Neck Surgery (AAO-HNS) member surgeons. Study Design Cross-sectional online survey. Subjects and Methods AAO-HNS members with a self-identified subspecialty interest either in sleep medicine or general otolaryngology were asked to complete an online survey, each respondent rated (5-point Likert scale) the perceived quality of their education and training and the role of specific factors in selection, both for procedure categories (eg, all hypopharyngeal) and individual procedures. Responses were examined for the entire group and for subgroups. Results Response rate was 27% (163/610). Sixty-five percent of respondents rated their surgical OSA education and training during postgraduate continuing medical education (CME) courses as of high quality, compared with 39% for residency/fellowship and 4% for medical school (P < 0.01). For individual hypopharyngeal procedures, over 40% of respondents reported limited training (except for tongue radiofrequency), and over 30% raised concerns about scientific evidence and reimbursement. Surgeon personal experience suggested treatment benefits without clearly favoring individual procedures. Respondents noted that patients were reluctant to undergo procedures, despite treatment recommendations, particularly maxillomandibular advancement. The sleep medicine subgroup reported higher ratings for education and training quality, research evidence, and personal experience with hypopharyngeal procedures. Concerns about adequate education and training, the quality of research evidence, and reimbursement issues were major factors in procedure selection. Conclusion Multiple factors affect procedure selection. Surgeons identify concerns regarding education and training and research evidence.

Controlled release of hepatocyte growth factor from a bovine acellular scaffold for vocal fold reconstruction

A bovine acellular scaffold was found to facilitate tissue remodeling in a rat model of vocal fold injury, whereas hepatocyte growth factor (HGF) has been shown to have an antiscarring effect in the larynx. This study examined the loading and release kinetics of HGF in vitro, and the potential of the acellular scaffold as a timed-release system for the delivery of HGF in vivo. Bilateral wounds were created in the posterior vocal folds of 20 rats, with HGF-loaded acellular scaffolds implanted into the wounds unilaterally, and scaffolds without HGF implanted into the contralateral vocal folds as control. The rats were humanely sacrificed after 3, 7, 30, and 90 days and their larynges were examined histologically and immunohistochemically. Expressions of key matrix proteins in the vocal fold coronal sections were quantified by digital image analysis. Results demonstrated a gradual, sustained release of HGF for at least 7 days in vitro, consistent with the detection of glycosaminoglycans inherent of the scaffold. In rat vocal folds implanted with HGF-loaded scaffolds, apparently fewer inflammatory cells were observed 3 days after surgery when compared to the control. The mean relative densities of collagen III and hyaluronic acid were significantly lower than those of the control 7 days after surgery. Scaffold implants were apparently degraded by 3 months in all animals, with no evidence of fibrosis or calcification. These data suggested that the bovine acellular scaffold could be promising for the exogenous delivery of select growth factors in vivo.

Roller blade falls - A new cause of temporal bone fractures: Case reports

Skating on wheels-in-line skates (roller blading) is an increasingly popular activity. We present two cases of temporal bone fractures from roller blading falls, and review the literature on temporal bone fractures resulting from recreational activities. Since trauma from roller blading may result in significant morbidity, the use of helmets is strongly recommended.

Localization of laminin isoforms in the guinea pig cochlea

Objective: To elucidate the pathogenesis of inner ear disorders by examining the distribution of a major component of basement membranes, the glycoprotein laminin.

P012: Consonant and Vowel Acquisition in Cochlear Implant Children

OBJECTIVES: Determine predictors of the final outcome of persistent perforation after removal of long-stay ventilation tubes, and whether the time for the perforation to heal was related to the initial size of the perforation and the time from intial insertion to removal. METHODS: Twenty patients and 23 ears studied. Study period, 2003 to 2006. Variables recorded included size of the perforations as percentage of drum area, and time taken to heal in months. A Kaplan-Meier analysis was done stratifying by the intial size of perforation. Logrank test & Cox’s proportional hazard model were used to analyse the relationship between the predictors and outcome. RESULTS: The Kaplan-Meier analysis appeared to show patients with larger perforations took longer to heal (median time to heal of 104 days in patients with less than 10% size, compared with 274 days in those with 15-20% perforations). Using Logrank test with size of the perforation as the predictor variable, the relationship between initial size of perforation and time to heal was shown to be stastically significant (P 0.03). Cox’s proportional hazard model with length of time ventilation tube remained in place as predictor variable also showed the longer the tube was left in, the longer it took to heal (P 0.026). CONCLUSIONS: The intial size of the perforation will predict the length of time taken for the perforation to heal. Although tubes that have been in place longer are associated with longer healing time, the size of this effect is marginal.