Context. Classical Be stars are rapid rotators of spectral type late O to early A and luminosity class V-III, which exhibit Balmer emission lines and often a near infrared excess originating in an ...equatorially concentrated circumstellar envelope, both produced by sporadic mass ejection episodes. The causes of the abnormal mass loss (the so-called Be phenomenon) are as yet unknown. Aims. For the first time, we can now study in detail Be stars outside the Earth’s atmosphere with sufficient temporal resolution. We investigate the variability of the Be Star CoRoT-ID 102761769 observed with the CoRoT satellite in the exoplanet field during the initial run. Methods. One low-resolution spectrum of the star was obtained with the INT telescope at the Observatorio del Roque de los Muchachos. A time series analysis was performed using both cleanest and singular spectrum analysis algorithms to the CoRoT light curve. To identify the pulsation modes of the observed frequencies, we computed a set of models representative of CoRoT-ID 102761769 by varying its main physical parameters inside the uncertainties discussed. Results. We found two close frequencies related to the star. They are 2.465 cd-1 (28.5 μHz) and 2.441 cd-1 (28.2 μHz). The precision to which those frequencies were found is 0.018 cd-1 (0.2 μHz). The projected stellar rotation was estimated to be 120 kms-1 from the Fourier transform of spectral lines. If CoRoT-ID 102761769 is a typical Galactic Be star it rotates near the critical velocity. The critical rotation frequency of a typical B5-6 star is about 3.5 cd-1 (40.5 μHz), which implies that the above frequencies are really caused by stellar pulsations rather than star’s rotation.
Abstract Objective Establish the time to safely and efficiently perform cochlear implantation (CI) in a university-based academic center. Study Design Case series with chart review. Setting Academic ...neurotologic referral center. Patients 424 patients who underwent CI surgery between 2002 and 2010. Intervention Unilateral, bilateral or revision CI using commercially available devices approved for use in the United States. Main outcome measures: mean surgical duration (SD) and mean total operative room time (TORT). Results Overall mean SD for all 424 patients was 83 ± 30 min (min) whereas the mean TORT was 135 ± 56 min. The mean SD for unilateral CI was 84 ± 18 min for the first implant and 82 ± 22 min for the second implant (p = 0.55). The SD for primary and revision CI was 83 ± 18 min and 85 ± 36 min, respectively (p = 0.51). The mean SD for pediatric and adult CI was 83 ± 21 min and 83 ± 18 min, respectively (p = 0.92). The mean SD without resident assistance was 74 ± 14 min whereas with the assistance of a resident the mean SD was 84 ± 20 min (p = 0.02). When ossification was encountered the mean SD was 90 ± 32 min compared to 82 ± 19 min when absent (p < 0.001). An association was found between TORT or SD, and the year of surgery, presence of ossification and the involvement of an assistant. Conclusion In a university-based academic center, CI surgery can be safely and efficiently performed, supporting future cost-effectiveness analysis of its current practice.
Menière's disease (MD) is characterized by episodes of vertigo, tinnitus, and sensorineural hearing loss. In the setting of bilateral deafness due to MD alone or contralateral pathology, cochlear ...implantation (CI) improves hearing. Active MD is characterized by fluctuating auditory symptoms and vertigo; whereas remittance of vertiginous symptoms and severe, permanent sensorineural hearing loss characterizes the inactive disease state. This study evaluates outcomes for MD patients compared with the general CI population and assesses if disease activity affects implant outcomes.
Retrospective chart review.
Tertiary referral center.
Twenty-four patients with MD that received CI (7 active, 16 inactive, and 1 Probable Menière's), and 24 age-matched controls.
Cochlear implantation.
Word Recognition Score, Sentence Recognition Score (SRS), and Speech Reception Threshold.
Best-aided preoperative and postoperative audiometric data were compared per ear between MD patients and controls and stratified by disease status using descriptive statistics with mixed-effects modeling. Patients with MD derived significantly more benefit from CI than controls when comparing differences between preoperative and postoperative levels for Word Recognition Score (12.2%, p = 0.0236), SRS (12.8%, p = 0.0375), and Speech Reception Threshold (-14.4 dB, p = 0.0188). Active disease status does not negatively impact CI outcomes and patients with active MD may benefit from greater gains in SRS (23.5%, p = 0.0107).
CI provides greater gains in functional hearing for patients with MD compared with age-matched controls. Patients with active MD seem to perform better with respect to SRS following CI than patients with inactive status.
Objective: Chronic tympanic membrane perforations are a common problem in the United States. A high number of these cases results from placement of pressure equalization tubes. These perforations may ...initially be treated with paper patch techniques and although safe and well tolerated, the procedure demonstrates poor efficacy. The ideal treatment for small perforations should be rapid, minimally invasive, and efficacious. Calcium alginate‐based tissue engineered tympanic membrane patches represent an attractive option, but in vivo data are required.
Methods: A controlled prospective study of tympanic membrane perforation repair using a well‐known chinchilla model of chronic tympanic membrane perforation was performed. Calcium alginate‐based tympanic membrane patches were created using computer‐aided design techniques. A previously described chinchilla model of chronic tympanic membrane perforations was used to create stable perforations ranging from 2 to 5 mm. Ears with chronic perforations were divided into three groups: control (no patch), paper patch, and calcium alginate plugs. At 10 weeks postimplantation, all animals were killed and inspected both grossly and histologically for healing.
Results: In the chinchilla model, the alginate grafts demonstrated significantly improved healing rates over both the untreated control group (spontaneous repair) and the paper patch group; nine of 13 healed in the alginate group versus two of nine healed in the paper patch group (P < .05) versus one of 11 healed in the control group (P < .05).
Conclusion: Calcium alginate tympanic membrane perforation patches offer a significant advantage in the repair of chronic perforations over traditional techniques in the chinchilla perforation model and may offer attractive opportunities in the clinical setting.
Abstract Congenital labyrinthine cholesteatoma can cause varying degrees of hearing loss and vertigo. Hearing preservation is not always possible when treatment involves total labyrinthectomy. Since ...1969, there have been several case reports and case series documenting hearing preservation following surgical treatment of congenital labyrinthine cholesteatoma. However, none of the case reports or case series documents the patients’ vestibular complaints after surgery. Herein, we report a case series of four patients who were treated with the goal of hearing preservation and resolution of vertigo after partial or complete removal of the bony labyrinth for congenital inner ear cholesteatoma. We will also discuss possible explanations for the mechanisms of preservation of hearing and vestibular function with a review of the current literature.
The endolymphatic sac tumor is a slow-growing, locally aggressive neoplasm that originates from the epithelium of the endolymphatic sac and duct. Disease progression can lead to profound ...sensorineural hearing loss, posterior fossa invasion, brainstem compression, drop metastasis, and eventual death. Early diagnosis and surgical attention are the primary objectives in the management of patients who have endolymphatic sac tumor. This article describes the latest rationale and techniques for hearing preservation surgery and a review of the latest developments surrounding this disease entity.
The pathophysiology of cholesteatoma Semaan, Maroun T; Megerian, Cliff A
Otolaryngologic clinics of North America,
12/2006, Letnik:
39, Številka:
6
Journal Article
Recenzirano
The pathogenesis of middle ear cholesteatoma continues to be highly debated. In recent years, there has been a substantial improvement in the understanding of the pathophysiology of this disease. ...This chapter provides a summary of the history and evolution of cholesteatoma and a review of the recent literature that pertains to the pathophysiology of congenital and acquired cholesteatoma. An emphasis is placed on the mechanism of osteolysis and the factors predictive of aggressiveness and recidivism.
To analyze audiometric outcomes after bilateral cochlear implantation in patients with isolated enlarged vestibular aqueduct (EVA) syndrome and associated incomplete partition (IP) malformations. ...Secondary objective was to analyze rate of cerebrospinal fluid (CSF) gusher in patients with IP-EVA spectrum deformities and compare this with the existing literature.
Retrospective chart review.
Thirty-two patients with EVA syndrome who received unilateral or bilateral cochlear implants between June 1999 and January 2014 were identified in the University Hospitals Case Medical Center cochlear implant database. Isolated EVA (IEVA) and Incomplete Partition Type II (IP-II) malformations were identified by reviewing high-resolution computed tomography (HRCT) imaging. Demographic information, age at implantation, surgical details, postimplantation audiometric data including speech reception thresholds (SRT), word, and sentence scores were reviewed and analyzed. Intra- and postoperative complications were analyzed as well and compared with the literature.
Seventeen patients (32 implanted ears) had pediatric cochlear implantation for EVA-associated hearing loss. Data from 16 controls (32 implanted ears) were used to compare audiometric and speech outcomes of EVA cohort. Mean age at implantation was 6.8 years for EVA cohort and 6.0 years for controls. There was no statistically significant difference in long-term postoperative SRT, monaurally aided word scores, and binaurally tested word scores between pediatric EVA group and controls. The EVA patients had a long-term mean sentence score of 85.92%. A subset of EVA patients implanted at mean age of 3.18 years (n = 15 ears) had similar audiometric outcomes to another control group with Connexin 26 mutations (n = 20 ears) implanted at a similar age. Further subset analysis revealed no significant differences in age at implantation, SRT, and word scores in patients with IEVA and IP-II malformation. There was no significant association between size of vestibular aqueduct and age at implantation. There was no CSF gusher or other intra- or postoperative complications reported in our series.
Bilateral sequential cochlear implantation can be performed safely in patients with EVA. Audiometric outcomes are excellent and comparable to pediatric cochlear implant patients with no malformations. CSF gusher rates can be minimized by trans-round window approach. Further long-term studies are needed to identify differences within IP-EVA spectrum deformities, audiometric outcomes, and proportions of EVA patients who will need cochlear implantation for hearing rehabilitation.
Summary
Background
A transparent and explicit reporting on authors’ contributions to the development of clinical practice guidelines and on panelists’ characteristics is essential for their ...credibility and trustworthiness. We did not find published studies on authorship or panel involvement in clinical practice guidelines.
Objective
To describe the approach to authorship in reports of clinical practice guidelines, and the characteristics of individual authors.
Methods
We conducted a cross‐sectional survey of guidelines listed in the National Guideline Clearing House (NGC) in 2016. We ed data on the general characteristics of the guidelines, report approach to authorship, and individual authors characteristics. Data ion was in duplicate and independent manner using standardised form. Data analyses were both descriptive and regression analyses.
Results
Overall, 139 eligible guidelines with published papers were identified. Of these, 48 (35%) included a group authorship statement in the author byline. A third of these guidelines (n = 45; 32%) reported on authors’ contributions, while about half of the guidelines (n = 74; 53%) reported who of the authors served as panel members. Around one‐fifth of the guidelines (n = 30; 22%) reported group membership (eg, content expert, patient representative) for at least 1 author. Less than one‐seventh of the eligible guidelines indicated who selected the panel members (n = 18; 13%), reported the types of panel members (n = 18; 13%) or the selection criteria (n = 12; 9%). Higher journal impact factor was associated with both “reporting of the author contributions” (OR = 1.07) and “the inclusion of a panel membership section in the guideline report” (OR = 1.21).
Conclusion
Low percentages of clinical practice guidelines report information on important aspects of authorship and characteristics of individual authors. Better reporting of some of these criteria was associated with journal impact factor.
Abstract Objectives To evaluate the long-term efficacy of endolymphatic sac shunt techniques with and without local steroid administration. Study design Retrospective case series and patient survey. ...Setting Tertiary university hospital. Patients Meniere's disease (MD) patients that failed medical therapy and subsequently underwent an endolymphatic sac shunt procedure. All patients had definitive or probable MD and at least 18-months of follow-up. Interventions Three variations on endolymphatic sac decompression with shunt placement were performed: Group A received no local steroids, Group B received intratympanic dexamethasone prior to incision, and Group C received dexamethasone via both intratympanic injection and direct endolymphatic sac instillation. Main outcome measure(s) Vertigo control, hearing results, and survey responses. Results Between 2002 and 2013, 124 patients with MD underwent endolymphatic sac decompression with shunt placement. 53 patients met inclusion criteria. Groups A, B, and C had 6 patients, 20 patients, and 27 patients, respectively. Mean follow-up was 56 months. Vertigo control improved in 66%, 83%, and 93% of Groups A, B, and C. Functional level improved for Group B (− 2.0) and Group C (− 2.2) but was unchanged in Group A. Pure-tone average and speech discrimination scores changed by + 22 dB and − 30%, + 6 dB and − 13%, and + 6 dB and − 5% in Groups A, B, and C. The long-term hearing results were significantly better with steroids (Groups B and C) according to the AAO-HNS 1995 criteria but did not meet significance on non-parametric testing. Conclusions Endolymphatic sac shunt procedures may benefit from steroid instillation at the time of shunt placement.
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