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Dive into the research topics where David R. Friedmann is active.

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Featured researches published by David R. Friedmann.


Laryngoscope | 2009

Clinical spectrum of patients with erosion of the inner ear by jugular bulb abnormalities

David R. Friedmann; B. Thuy Le; Bidyut K. Pramanik; Anil K. Lalwani

Anatomic variants of the jugular bulb (JB) are common; however, abnormalities such as large high riding JB and JB diverticulum (JBD) are uncommon. Rarely, the abnormal JB may erode into the inner ear. The goal of our study is to report a large series of patients with symptomatic JB erosion into the inner ear.


Otology & Neurotology | 2013

The effects of residual hearing in traditional cochlear implant candidates after implantation with a conventional electrode.

Maura Cosetti; David R. Friedmann; Zhu Bz; Selena E. Heman-Ackah; Fang Y; Keller Rg; William H. Shapiro; John T. Roland; Susan B. Waltzman

Objective To analyze the effects of residual hearing on postoperative speech performance in traditional cochlear implant (CI) patients implanted with a conventional electrode. Study Design Retrospective review. Setting Academic tertiary referral center. Patients A total of 129 adults implanted by a single surgeon at a tertiary care facility between June 2005 and November 2010 with measurable preoperative pure tone thresholds at any frequency were included. Intervention Cochlear implantation with a conventional electrode via an anterior inferior cochleostomy. Main Outcome Measure Speech perception using monosyllabic word scores in quiet and sentences in quiet and noise in the electric (CI-only) condition of the implanted ear. Preservation of hearing was defined as complete for postoperative thresholds within 10 dB of preimplant values and partial if greater than 11 dB. Pure tone audiometry and speech perception testing were performed preoperatively and at regular intervals postoperatively, with the 1-year evaluation being the final outcome period. Results Preservation at any frequency or level was not a factor in speech perception outcome, although preservation was more common in low frequencies. Hearing preservation was correlated with younger age at implantation, but was not related to length of hearing loss, cause of deafness, device type, sex, preoperative speech performance, or low-frequency pure-tone average. Conclusion Hearing can be preserved in traditional CI patients implanted with a conventional electrode. Although preservation of hearing may have implications for future technology, it is not currently correlated with speech performance in the CI-only condition.


Otology & Neurotology | 2011

Development of the Jugular Bulb: A Radiologic Study

David R. Friedmann; Jan Eubig; Megan Mcgill; James S. Babb; Bidyut K. Pramanik; Anil K. Lalwani

Objective: Jugular bulb (JB) abnormalities such as JB diverticulum and high-riding JBs of the temporal bone can erode into the inner ear and present with hearing loss, vestibular disturbance, and pulsatile tinnitus. Their cause and potential to progress remain to be studied. This comprehensive radiologic study investigates the postnatal development of the venous system from transverse sinus to internal jugular vein (IJV). Setting: Academic medical center. Patients, Intervention, Main Outcome Measure: Measurements of the transverse and sigmoid sinus, the JB, IJV, and carotid artery were made from computed tomographic scans of the neck with intravenous contrast in infants (n = 5), children (n = 13), adults (n = 35), and the elderly (n = 15). Results: Jugular bulbs were not detected in patients younger than 2 years, enlarged in adulthood, and remained stable in the elderly. The venous system was larger in men than in women. From transverse sinus to IJV, the greatest variation in size was just proximal and distal to the JB with greater symmetry observed as blood returned to the heart. Right-sided venous dominance was most common occurring in 70% to 80% of cases. Conclusion: The JB is a dynamic structure that forms after 2 years, and its size stabilizes in adulthood. The determinants in its exact position and size are multifactorial and may be related to blood flow. Improved understanding of this structures development may help to better understand the cause of the high-riding JB and JB diverticulum, both of which may cause clinical symptoms.


Otolaryngology-Head and Neck Surgery | 2011

Prevalence of Jugular Bulb Abnormalities and Resultant Inner Ear Dehiscence: a Histopathologic and Radiologic Study:

David R. Friedmann; Jan Eubig; Leon S. Winata; Bidyut K. Pramanik; Saumil N. Merchant; Anil K. Lalwani

Objective Jugular bulb abnormalities (JBA), including high-riding jugular bulb (HRJB) and jugular bulb diverticulum (JBD), can erode into the inner ear. In this study, the authors investigate the prevalence and consequences of JBA and their erosion into inner ear structures using temporal bone histopathology and computed tomography (CT). Study Design Cross-sectional study of temporal bone histopathology and radiology. Setting Academic medical center. Subjects and Methods In total, 1579 temporal bone specimens and 100 CT of the temporal bones (200 ears) were examined for JBA and any associated dehiscence of inner ear structures. Temporal bone specimens were examined for histological consequences of inner ear erosion. Jugular bulb dimensions were measured on axial CT scans and compared across groups. Accompanying demographic and clinical information were reviewed. Results High jugular bulbs were noted in 8.2% (130/1579) of temporal bone specimens and in 8.5% (17/200) of temporal bone CT. The prevalence of JBA increases during the first 4 decades of life and stabilizes thereafter. High-riding jugular bulbs eroded inner ear structures such as the vestibular aqueduct, vertical facial nerve, or posterior semicircular canal in 2.8% (44/1579) of cases histologically and 1.5% (3/200) radiologically. In most, jugular bulb–mediated inner ear dehiscence was clinically and radiologically silent. Conclusion Jugular bulb abnormalities are common. They are present in 10% to 15% individuals and are primarily acquired by the fourth decade of life. In 1% to 3% of cases, the HRJB erodes into the inner ear and most frequently involves the vestibular aqueduct.


Archives of Otolaryngology-head & Neck Surgery | 2012

A Clinical and Histopathologic Study of Jugular Bulb Abnormalities

David R. Friedmann; Jan Eubig; Leon S. Winata; Bidyut K. Pramanik; Saumil N. Merchant; Anil K. Lalwani

OBJECTIVE To further define the spectrum of clinical presentation and explore the histologic sequelae of jugular bulb abnormalities (JBAs). DESIGN Retrospective review. SETTING Academic medical center. PATIENTS Thirty patients with radiologic evidence of inner ear dehiscence by JBA. MAIN OUTCOME MEASURE Thirty patients with radiologic inner ear dehiscence by JBA and 1579 temporal bone specimens were evaluated for consequences from JBA. RESULTS We found that JBA-associated inner ear dehiscence could be identified on computed tomography of the temporal bone but not on magnetic resonance imaging scan. Jugular bulb abnormalities eroded the vestibular aqueduct most often (in 25 patients), followed by the facial nerve (5 patients) and the posterior semicircular canal (4 patients). Half of the patients (15) were asymptomatic. Results from vestibular evoked myogenic potential (VEMP) tests were positive in 8 of 12 patients with inner ear dehiscence. Histologically, only 2 of 41 temporal bones with dehiscence of the vestibular aqueduct demonstrated endolymphatic hydrops. CONCLUSIONS Jugular bulb abnormalities can erode into the vestibular aqueduct, facial nerve, and the posterior semicircular canal. While symptoms may include pulsatile tinnitus, vertigo, or conductive hearing loss, in contrast to earlier reports, half of the patients were asymptomatic. Dehiscence of vestibular aqueduct rarely leads to clinical or histologic hydrops. The VEMP testing was useful in confirming the presence of inner ear dehiscence due to JBAs. Because the natural history of JBAs is unknown, these patients should be followed closely to evaluate for progression of the JBA or development of symptoms.


Otology & Neurotology | 2016

Single-sided Deafness Cochlear Implantation: Candidacy, Evaluation, and Outcomes in Children and Adults.

David R. Friedmann; Omar H. Ahmed; Sean O. McMenomey; William H. Shapiro; Susan B. Waltzman; J. Thomas Roland

Objectives: Although there are various available treatment options for unilateral severe-to-profound hearing loss, these options do not provide the benefits of binaural hearing since sound is directed from the poorer ear to the better ear. The purpose of this investigation was to review our centers experience with cochlear implantation in such patients in providing improved auditory benefits and useful binaural hearing. Study Design: Retrospective chart review. Methods: Twelve adult patients and four pediatric patients with unilateral severe-to-profound hearing loss received an implant in the poorer ear. Outcome measures performed preoperatively on each ear and binaurally included consonant–nucleus–consonant (CNC) monosyllabic words and sentences in noise. The mean pure-tune average in the better ear was within normal range. Results: Test scores revealed a significant improvement in CNC and sentence in noise test scores from the preoperative to most recent postoperative evaluation in the isolated implant ear. All adult subjects use the device full-time. Conclusions: The data reveal significant improvement in speech perception performance in quiet and in noise in patients with single-sided deafness after implantation. Performance might depend on factors including length of hearing loss, age at implantation, and device usage.


Laryngoscope | 2012

Venous malformations of the temporal bone are a common feature in CHARGE syndrome

David R. Friedmann; Misha Amoils; John A. Germiller; Lawrence R. Lustig; Christine M. Glastonbury; Bidyut K. Pramanik; Anil K. Lalwani

CHARGE (Coloboma of the eye, Heart defects, Atresia of the choanae, Retardation of growth and/or development, Genital and/or urinary abnormalities, and Ear abnormalities and/or deafness) syndrome is a genetic disorder with prominent otolaryngologic features including choanal atresia and inner ear malformations. Recent experience with venous malformations during cochlear implant surgery prompted this study to define the spectrum of venous abnormalities in CHARGE and their surgical implications in otology.


Cytoskeleton | 2008

MYH9-siRNA and MYH9 mutant alleles: expression in cultured cell lines and their effects upon cell structure and function.

Yan Li; David R. Friedmann; Anand N. Mhatre; Anil K. Lalwani

MYH9 encodes a class II nonmuscle myosin heavy chain-A (NMHC-IIA), a widely expressed 1960 amino acid polypeptide, with translated molecular weight of 220 kDa. From studies of type II myosin in invertebrates and analogy with the skeletal and smooth muscle myosin II, NMHC-IIA is considered to be involved in diverse cellular functions, including cell shape, motility and division. The current study assessed the consequences of two separate, naturally occurring MYH9 dominant mutant alleles, MYH9(R702C) and MYH9(R705H) linked to syndromic and nonsyndromic hearing loss, respectively, upon diverse NMHC-IIA related functions in two separate cultured cell lines. MYH9-siRNA-induced inhibition of NMHC-IIA in HeLa cells or HEK293 cells resulted in alterations in their shape, actin cytoskeleton and adhesion properties. However, HeLa or HEK293 cells transfected with naturally occurring MYH9 mutant alleles, MYH9(R702C) or MYH9(R705H), as well as in vitro generated deletion derivatives, MYH9(DeltaN592) or MYH9(DeltaC570), were unaffected. The effects of MYH9-siRNA-induced suppression underline the critical role of NMHC-IIA in maintenance of cell shape and adhesion. However, the results also indicate that the NMHC-IIA mutants, R702C and R705H do not inactivate or suppress the endogenous wild type NMHC-IIA within the HeLa or HEK293 cell assay system.


Cochlear Implants International | 2015

Effects of loss of residual hearing on speech performance with the CI422 and the Hybrid-L electrode

David R. Friedmann; Robert Peng; Yixin Fang; Sean O. McMenomey; J. Thomas Roland; Susan B. Waltzman

Abstract Objective Preservation of residual low-frequency hearing has become a priority in cochlear implantation. The purpose of this study was to compare rates of hearing preservation and effects on performance of loss of low-frequency acoustic hearing with two different length electrodes. Study design Retrospective chart review. Setting Tertiary Care Hospital. Patients Twelve patients were implanted with the CI422 a slim-straight electrode; the second group consisted of 10 patients implanted with the Hybrid-L, a shorter hearing preservation electrode. Main outcome measure Audiometric thresholds and speech perception measures. Results At 1 year, 3/10 (30%) patients with the Hybrid-L and 7/12 (58%) patients with the CI422 lost residual acoustic hearing resulting in a profound hearing loss in the implanted ear. In comparing these patients in particular, mean CNC words in the implanted ear were 72% in the CI422 electrode group and 15% in the Hybrid-L electrode group at 1 year (P = 0.03). While hearing preservation rates with the Hybrid-L tended to be better, among recipients who lost residual hearing, speech perception was better in those with the longer CI422 electrode. Conclusions With emphasis on preservation of residual hearing, patients need to be counseled regarding possible outcomes and options should loss of residual hearing occur following implantation. While shorter electrodes may have better rates of hearing preservation, the patients with the longer straight electrode in our study had significantly better speech understanding following the loss of residual hearing.


Laryngoscope | 2013

Simulation‐based training in advanced airway skills in an otolaryngology residency program

Milan R. Amin; David R. Friedmann

Life‐support training emphasizes the primacy of airway management. Acquiring these skills requires practice and exposure to events. Otolaryngology residents lack standardized training in advanced airway skills. This project aimed to create such a program by using simulation‐based methodology evaluated using specific educationally based tools.

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Leon S. Winata

Massachusetts Eye and Ear Infirmary

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Saumil N. Merchant

Massachusetts Eye and Ear Infirmary

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