Noise-induced hearing threshold shift among US adults and implications for noise-induced hearing loss: National Health and Nutrition Examination Surveys.

The objective of this study was to estimate the prevalence and evaluate the associated risk factors of the noise-induced hearing threshold shift (NITS) in the US adult population based on the National Health and Nutrition Examination Surveys (NHANES). The study population consisted of 5,418 individuals aged 20-69 years who had complete audiologic data from the NHANES database. Stringent criteria were used to define NITS. Prevalence of unilateral, bilateral, and total NITS and their association with several socio-demographic and hearing-related factors were evaluated. The prevalence of unilateral, bilateral, and total NITS was 9.4, 3.4 and 12.8%, respectively. Prevalence of bilateral NITS was higher in subjects with older age, male gender, white (non-Hispanic) and Hispanic ethnicities, education level less than or equal to high school diploma, married/living with partner status, Mexico as country of birth, service in armed forces, smoking history, diabetes, and different kinds of noise exposure. Odds of NITS were only higher in older people, males, and smokers. This study provides comprehensive information on the prevalence of NITS in the US adult population and its associated risk factors. More targeted interventions may be done for educational, preventative, and screening purposes.

Transmastoid approach to temporal bone cerebrospinal fluid leaks.

PURPOSE: The aim of the study was to evaluate various presentations and treatment options for spontaneous cerebrospinal fluid (CSF) leakage originating in the temporal bone. MATERIALS AND METHODS: Clinical data and imaging results for 18 ears (15 patients) presenting with spontaneous CSF leakage originating in the temporal bone were reviewed. Average follow-up period was 13.5 months. The main outcome measure was presence of persistent CSF leak postoperatively. A standard postauricular mastoidectomy was performed. RESULTS: Fifteen patients diagnosed with spontaneous CSF leakage over an 8-year period including 3 treated for bilateral disease were included in the study. The age ranged between 33 and 83 years. Presenting symptoms included serous otitis media (44%), persistent otorrhea after tympanostomy tube placement (28%), and meningitis (28%). Preoperative diagnosis was made using imaging studies and was substantiated by observation of CSF leakage and dural herniation intraoperatively. Treatment was eustachian tube plugging (5%), mastoidectomy with fat obliteration (61%), middle fossa approach with extradural (17%), intradural repair (5%), or combined middle fossa and transmastoid (TM) approach (11%). Successful treatment was obtained in 17 of the 18 cases. The last 9 patients in the series underwent TM approach alone for repair with no treatment failures. CONCLUSIONS: Repair of defects in tegmen mastoideum and posterior fossa can be successfully achieved on an outpatient basis without regard to size and multitude of defects via TM approach. This approach obviates the need for a craniotomy or lumbar drain.

Laser treatment of scars.

Recent advances in optical technologies have produced laser systems capable of optimizing the appearance of scars from various etiologies. Laser treatment can commence as early as the time of the initial injury and as late as several years after the injury. Optimal results can now be attained with minimal down time. Herein, we review several available optical technologies for treatment of surgical, traumatic, and inflammatory scars, based upon our clinical experience.

Porcine cartilage model for simulation of nasal tip aesthetics and mechanics.

BACKGROUND: The aesthetics of the human nose is highly dependent on the complex structure of the lower lateral cartilages (LLC). Understanding optimum shape and mechanical properties of the LLC is pivotal to achieving satisfactory results in nasal tip rhinoplasty. OBJECTIVE: The authors introduce an ex vivo animal model to replicate the shape and mechanics of human nasal LLC as a tool for research and surgical education. METHODS: Seven fresh pig heads were obtained from a local butcher shop. Nasal cartilage was harvested in a replicable manner and fashioned into appropriate shapes and dimensions based on the authors' human cadaver studies. Sutures were placed to approximate the cartilage pairs into appropriate human anatomical position. RESULTS: The porcine cartilage model replicated analogous structures, including the medial crura and the lateral crura, with appropriate cephalic orientation and domal angles. The anterior-posterior dimensions of the medial crura, intermediate crura, and lateral crura were 4 mm, 6 mm, and 10 mm, respectively. Cartilage thickness was approximately 1 mm throughout the specimen. Cephalic orientation of the lateral crura was sculpted to 45°. The average angle of divergence was 54° and varied according to the physiological shape of the porcine nasal vault (range, 43-74°). Average interdomal distance was 13.3 mm (range, 9-18 mm), and average domal width was 6.2 mm (range, 5-7 mm). CONCLUSIONS: This novel porcine model mimics human LLC and is inexpensive, easy to construct, and highly replicable. This model can be used as a valuable educational resource for training novice surgeons in the principles of nasal tip rhinoplasty. Additionally, our construct has broad applications in studying LLC geometry and mechanics.

Similar histologic features and immunohistochemical staining in microcystic and macrocystic lymphatic malformations.

BACKGROUND: Lymphatic malformations are benign but potentially life-threatening lesions mostly found in the head and neck. They can be classified into two types: microcystic and macrocystic. Microcystic lesions are more difficult to treat. In this study, we describe the histologic features and expression of lymphatic endothelial markers in microcystic and macrocystic lymphatic malformations and correlate clinical data with histologic and immunohistochemical data. METHODS AND RESULTS: This is a retrospective study of clinical data and tissue specimens which were collected from 18 children who underwent surgical excision of lymphatic malformations. The clinical data were analyzed with descriptive statistics. Microcystic and macrocystic lesion specimens were examined with Movat pentachromic stain and immunohistochemistry for lymphatic endothelial markers. Patients with microcystic lesions were more likely to have mucosal involvement, recurrence, and higher stages of disease, compared with those with macrocystic lesions. Microcystic and macrocystic lesions stained similarly with Movat pentachromic stain and for lymphatic endothelial cell markers. CONCLUSIONS: Although microcystic and macrocystic lesions have different clinical behavior, they have indistinguishable histological features and immunohistochemical staining for markers of lymphatic endothelium. These findings suggest that both microcystic and macrocystic lesions are derived from similar tissue but may behave differently based on their anatomic microenvironment.

Facial nerve anatomy, dissection and preservation in lymphatic malformation management.

OBJECTIVE: To describe facial nerve anatomy and surgical techniques used for safe lymphatic malformation resection of malformation involving the facial nerve. METHODS DESIGN: retrospective case series. SETTING: tertiary pediatric hospital. SUBJECTS: record review of lymphatic malformation patients after facial nerve dissection, from 1996 to 2005. Data collected included: facial nerve function, relationship of lymphatic malformation to facial nerve, facial nerve anatomy, dissection extent and clinical outcome. RESULTS: Sixteen patients who met inclusion criteria underwent a total of 21 facial nerve dissections. Mean age at dissection was 48 months (range 1-72 months). Mean follow-up was 38 months (range 8-144 months). Pre-operative lymphatic malformation stage by patient: II=7/16, III=4/16, IV=2/16 and V=3/16. Higher stage lymphatic malformations required more extensive dissections (p=0.026). Pre-operative facial nerve function was House-Brackmann grade (HBG)-1 in 20, and HBG-6 in 1. Eight months postoperatively, facial nerve function was HBG-1 in 18, HBG-2 in 1, and HBG-6 in 2. The facial nerve was surrounded by lymphatic malformation in 10/21, deep to the lymphatic malformation in 5/21, superficial to the lymphatic malformation in 4/21, and not identified in 2/21. Imaging studies predicted facial nerve position in 15/21 procedures. Antegrade nerve dissection was performed in 10/21, retrograde in 7/21 and not done in 2/21. Abnormally elongated facial nerve was identified in 11/21 cases and required more extensive dissection (p=0.040). Facial nerve monitoring was used in 15/21 dissections. Clinical outcomes were felt to be good in 19/21 dissections. CONCLUSIONS: In lymphatic malformation surgery, the facial nerve is often abnormally elongated and encompassed by malformation. Pre-operative imaging, facial nerve identification and dissection allow excellent postoperative facial nerve function.

The prevalence and characteristics of tinnitus in the youth population of the United States.

OBJECTIVES/HYPOTHESIS: To evaluate the prevalence, characteristics, and associated risk factors of tinnitus in U.S. adolescents. STUDY DESIGN: Cross-sectional analyses of U.S. representative demographic and audiometric data, the National Health and Nutrition Examination Survey (NHANES) 2005 to 2008. METHODS: The study population consisted of 3,520 individuals aged 12 to 19 years with complete tinnitus-related data. Tinnitus was defined as the presence of ringing or buzzing in the ears lasting for at least 5 minutes during the preceding 12 months. In addition, we defined a chronic tinnitus subgroup as being bothered by tinnitus for more than 3 months. Demographic and other data regarding tinnitus, smoking, body mass index (BMI), anemia, hypertension, history of ear infections, tympanostomy tube placement, otoscopy, tympanometry and hearing thresholds, history of firearm use, and recreational and occupational exposure to noise were extracted and analyzed. RESULTS: Overall, tinnitus lasting 5 minutes or more in the preceding 12 months was reported by 7.5% of the 12- to 19-year-old population. This represents about 2.5 million adolescents in the United States. The prevalence of chronic tinnitus was 4.7%, corresponding to about 1.6 million adolescents in the United States. Multivariable-adjusted analysis revealed that both overall and chronic tinnitus were associated with female gender, low income, exposure to passive smoking, type A tympanogram, and occupational and recreational noise exposure. History of ≥ 3 ear infections and history of tympanostomy tube placement were associated only with overall tinnitus. CONCLUSIONS: Tinnitus afflicts a substantial portion of the youth population. Further investigation of the association between tinnitus and the identified risk factors is warranted.

Systematic assessment of noise amplitude generated by toys intended for young children.

OBJECTIVE: To systematically evaluate the noise generated by toys targeted for children and to compare the results over the course of 4 consecutive holiday shopping seasons. STUDY DESIGN: Experimental study. SETTING: Academic medical center. SUBJECTS AND METHODS: During 2008-2011, more than 200 toys marketed for children older than 6 months were screened for loudness. The toys with sound output of more than 80 dBA at speaker level were retested in a soundproof audiometry booth. The generated sound amplitude of each toy was measured at speaker level and at 30 cm away from the speaker. RESULTS: Ninety different toys were analyzed. The mean (SD) noise amplitude was 100 (8) dBA (range, 80-121 dBA) at the speaker level and 80 (11) dBA (range, 60-109 dBA) at 30 cm away from the speaker. Eighty-eight (98%) had more than an 85-dBA noise amplitude at speaker level, whereas 19 (26%) had more than an 85-dBA noise amplitude at a 30-cm distance. Only the mean noise amplitude at 30 cm significantly declined during the studied period (P < .001). There was no significant difference in mean noise amplitude of different toys specified for different age groups. CONCLUSION: Our findings demonstrate the persistence of extremely loud toys marketed for very young children. Acoustic trauma from toys remains a potential risk factor for noise-induced hearing loss in this age group, warranting promotion of public awareness and regulatory considerations for manufacture and marketing of toys.

In vivo electromechanical reshaping of ear cartilage in a rabbit model: a minimally invasive approach for otoplasty.

OBJECTIVE: To report the first successful study to date of in vivo electromechanical reshaping of ear cartilage in a rabbit model. METHODS: Ears of New Zealand white rabbits were reshaped using percutaneous needle electrode electromechanical reshaping (5 V for 4 minutes) and were then bolstered for 4 weeks. Ten ears were treated, with 2 undergoing sham procedures and serving as controls. The treatment was performed using a platinum array of electrodes consisting of 4 parallel rows of needles inserted across the region of flexures in the ear. After 4 weeks, the animals were killed, and the ears were photographed and sectioned for conventional light microscopy and confocal microscopy (live-dead fluorescent assays). RESULTS: Significant shape change was noted in all the treated ears (mean, 102.4°; range, 87°-122°). Control ears showed minimal shape retention (mean, 14.5°; range, 4°-25°). Epidermis and adnexal structures were preserved in reshaped ears, and neochondrogenesis was noted in all the specimens. Confocal microscopy demonstrated a localized zone of nonviable chondrocytes (<2.0 mm in diameter) surrounding needle sites in all the treated ears. CONCLUSIONS: Electromechanical reshaping can alter the shape of the rabbit auricle, providing good creation and retention of shape, with limited skin and cartilage injury. Needle electrode electromechanical reshaping is a viable technique for minimally invasive tissue reshaping, with potential applications in otoplasty, septoplasty, and rhinoplasty. Further studies to refine dosimetry parameters will be required before clinical trials.

Mechanical analysis of the effects of cephalic trim on lower lateral cartilage stability.

OBJECTIVE: To determine how mechanical stability changes in the lower lateral cartilage (LLC) after varying degrees of cephalic resection in a porcine cartilage nasal tip model. METHODS: Alar cartilage was harvested from fresh porcine crania (n = 14) and sectioned to precisely emulate a human LLC in size and dimension. Flexural mechanical analysis was performed both before and after cephalic trims of 0 (control), 4, and 6 mm. Cantilever deformation tests were performed on the LLC models at 3 locations (4, 6, and 8 mm from the midline), and the integrated reaction force was measured. An equivalent elastic modulus of the crura was calculated assuming that the geometry of the LLC model approximated a modified single cantilever beam. A 3-dimensional finite element model was used to model the stress distribution of the prescribed loading conditions for each of the 3 types of LLC widths. RESULTS: A statistically significant decrease (P = .02) in the equivalent elastic modulus of the LLC model was noted at the most lateral point at 8 mm and only when 4 mm of the strut remained (P = .05). The finite element model revealed that the greatest internal stresses was at the tip of the nose when tissue was flexed 8 mm from the midline. CONCLUSION: Our results provide the mechanical basis for suggested clinical guidelines stating that a residual strut of less than 6 mm can lead to suboptimal cosmetic results owing to poor structural support of the overlying skin soft-tissue envelope by an overly resected LLC.

Tympanomastoidectomy with otoendoscopy.

A cadaveric study was performed to test the hypothesis that intact-canal-wall mastoidectomy (ICWM) with otoendoscopy allows for equal or better visualization of the middle ear cavity structures when compared with canal-wall-down mastoidectomy (CWDM) with microscopy. Ten temporal bones were prepared with a reversible canal-wall-down tympanomastoidectomy technique. Five anatomic sites in each middle ear cavity (lateral epitympanum, posterior crus of the stapes, the sinus tympani, eustachian tube orifice, and round window niche) were marked with paint. Two otolaryngologists blinded to the purpose of the study viewed the temporal bones with the microscope. Following replacement of the posterior canal walls, the bones were then viewed with a 30° and a 70° otoendoscope. All visualized paint marks for each viewing were recorded and compared. We found that ICWM with 30° or 70° otoendoscopy provided significantly better visualization of the sinus tympani than did CWDM (p ≤ 0.001). There was no significant difference among the three methods in visualization of the lateral epitympanum, posterior crus of the stapes, and round window niche. With respect to the eustachian tube orifice, one of the observers reported significantly better visualization with CWDM (p = 0.036). With adjunctive otoendoscopy, it is not necessary to remove the posterior canal wall to adequately visualize or remove disease from various areas of the middle ear cleft. The use of otoendoscopy during cholesteatoma surgery may allow for more frequent preservation of the posterior canal wall and reduced rates of residual cholesteatoma, given the equal or better visualization of the middle ear cavity.

Use of lasers in acute management of surgical and traumatic incisions on the face.

This article is a clinically practical review structured around the specific applications of laser technologies used in acute management of soft tissue injuries in surgical incisions and trauma. Surgical and traumatic incisions and injuries provide the clinician with the unique opportunity to follow the progression and maturation of the wound healing response from a very early stage. There has been a recent interest in early cosmetic optimization of surgical and traumatic wounds on the face using optical technologies. Early clinical results for acute laser intervention starting immediately after suture removal or the first several weeks after repair have been very promising.

Airway procedures and hemangiomas: treatment patterns and outcome in U.S. pediatric hospitals.

OBJECTIVE: Characterize and compare care in children with hemangiomas, who do or do not undergo airway procedures. METHODS: National retrospective cohort study of patients aged 0-18 with hemangiomas, from 33 freestanding United States pediatric hospital discharge records, 2001-2005. The main outcome measures were therapy, readmission and mortality. RESULTS: Of 2890 patients diagnosed with hemangiomas, 337 (12%) underwent airway procedures. Most airway procedures were for patients between ages 1 and 11 months. Patients with hemangiomas and airway procedures had more steroid use (80%), increased readmission (30%), and increased mortality (2%) compared to hemangioma patients without airway procedures. Procedures (i.e. laser, open surgery, tracheotomy) and age over 4 months in airway procedure patients were associated with decreased readmission. Increased readmissions were associated with systemic steroid administration. CONCLUSION: Hemangioma patients who undergo airway procedures experience increased medical and surgical therapy compared to those who do not. Readmission is increased in patients with hemangiomas and airway procedures, but surgical intervention and age greater than 4 months decreased readmission.

Facial nerve mapping and monitoring in lymphatic malformation surgery.

OBJECTIVE: Establish the efficacy of preoperative facial nerve mapping and continuous intraoperative EMG monitoring in protecting the facial nerve during resection of cervicofacial lymphatic malformations. METHODS: Retrospective study in which patients were clinically followed for at least 6 months postoperatively, and long-term outcome was evaluated. Patient demographics, lesion characteristics (i.e., size, stage, location) were recorded. Operative notes revealed surgical techniques, findings, and complications. Preoperative, short-/long-term postoperative facial nerve function was standardized using the House-Brackmann Classification. Mapping was done prior to incision by percutaneously stimulating the facial nerve and its branches and recording the motor responses. Intraoperative monitoring and mapping were accomplished using a four-channel, free-running EMG. Neurophysiologists continuously monitored EMG responses and blindly analyzed intraoperative findings and final EMG interpretations for abnormalities. RESULTS: Seven patients collectively underwent 8 lymphatic malformation surgeries. Median age was 30 months (2-105 months). Lymphatic malformation diagnosis was recorded in 6/8 surgeries. Facial nerve function was House-Brackmann grade I in 8/8 cases preoperatively. Facial nerve was abnormally elongated in 1/8 cases. EMG monitoring recorded abnormal activity in 4/8 cases--two suggesting facial nerve irritation, and two with possible facial nerve damage. Transient or long-term facial nerve paresis occurred in 1/8 cases (House-Brackmann grade II). CONCLUSIONS: Preoperative facial nerve mapping combined with continuous intraoperative EMG and mapping is a successful method of identifying the facial nerve course and protecting it from injury during resection of cervicofacial lymphatic malformations involving the facial nerve.