Faculty Bibliography

OBJECTIVES: To determine the efficacy of cochlear implantation (CI) in prelingually deafened adolescent children and to evaluate predictive variables for successful outcomes. DESIGN: Retrospective medical record review. PARTICIPANTS: Children aged 10 to 17 years with prelingual hearing loss (mean length of deafness, 11.5 years) who received a unilateral CI (mean age at CI, 12.9 years). Intervention Unilateral CI. MAIN OUTCOME MEASURES: Standard speech perception testing (Consonant-Nucleus-Consonant [CNC] monosyllabic word test and Hearing in Noise [HINT] sentence test) was performed preoperatively, 1 year postoperatively (year 1), and at the last follow-up/end of the study (EOS). RESULTS: There was a highly significant improvement in speech perception scores for both HINT sentence and CNC word testing from the preoperative testing to year 1 (mean change score, 51.10% and 32.23%, respectively; P < .001) and from the preoperative testing to EOS (mean change score, 60.02% and 38.73%, respectively; P < .001), with a significantly greater increase during the first year (P < .001). In addition, there was a highly significant correlation between improvements in performance scores on the CNC word and HINT sentence speech perception tests and both age at CI and length of deafness at the year 1 testing (P </=.009) but not from the year 1 testing to EOS testing. Adolescents with progressive deafness and those using oral communication before CI performed significantly better than age-matched peers. CONCLUSIONS: Adolescents with prelingual deafness undergoing unilateral CI show significant improvement in objective hearing outcome measures. Patients with shorter lengths of deafness and earlier age at CI tend to outperform their peers. In addition, patients with progressive deafness and those using oral communication have significantly better objective outcomes than their peers

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 structure's development may help to better understand the cause of the high-riding JB and JB diverticulum, both of which may cause clinical symptoms

As science continues to unravel the genetic basis of disease, an understanding of genetics has become increasingly critical to the practicing clinician. Otorhinolaryngology, a comprehensive specialty in which the physician is responsible for delivering both medical and surgical care within their scope of practice, requires the practitioner to have a fund of knowledge in genetics to effectively communicate and counsel patients. This introductory chapter highlights what is known about the complexity of the human genome and various applications of genetics throughout the field of otorhinolaryngology to be discussed in subsequent chapters. These entities include the genetics of hearing impairment, skull base tumors, molecular genetics in head and neck cancer and systemic diseases with otolaryngologic features

OBJECTIVES/HYPOTHESIS: 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. STUDY DESIGN: Retrospective review in an academic medical center. METHODS: Eleven patients with JB abnormality eroding into the inner ear were identified on computed tomography (CT) scan of the temporal bone. RESULTS: Age at presentation was from 5 years to 82 years with six males and five females. The large JB or JBD eroded into the vestibular aqueduct (n = 9) or the posterior semicircular canal (n = 4). The official radiology report usually identified the JB abnormality; however, erosion into these structures by the JB was not mentioned in all but one case. All patients were symptomatic with five having conductive hearing loss (CHL) and three complaining of pulsatile tinnitus. Those with pulsatile tinnitus and four of five with CHL had erosion into the vestibular aqueduct. Vestibular evoked myogenic potential (VEMP) findings in three of six patients were consistent with dehiscence of the inner ear. CONCLUSIONS: High riding large JB or JBD can erode into the inner ear and may be associated with CHL and/or pulsatile tinnitus. CT scan is diagnostic and should be examined specifically for these lesions. As patients with pulsatile tinnitus may initially undergo a magnetic resonance imaging scan, identification of JB abnormality should prompt CT scan or VEMP testing to evaluate for inner ear erosion

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. Cell Motil. Cytoskeleton 2008. (c) 2008 Wiley-Liss, Inc

The MHC-encoded cofactor DM catalyzes endosomal loading of peptides onto MHC class II molecules. Despite evidence from in vitro experiments that DM acts to selectively edit the repertoire of class II:peptide complexes, the consequence of DM expression in vivo, or a predictive pattern of DM activity in the specificity of CD4 T cell responses has remained unresolved. Therefore, to characterize DM function in vivo we used wild-type (WT) or DM-deficient (DM(-/-)) mice of the H-2(d) MHC haplotype and tested the hypothesis that DM promotes narrowing of the repertoire of class II:peptide complexes displayed by APC, leading to a correspondingly selective CD4 T cell response. Surprisingly, our results indicated that DM(-/-) mice do not exhibit a broadened CD4 T cell response relative to WT mice, but rather shift their immunodominance pattern to new peptides, a pattern associated with a change in class II isotype-restriction. Specifically, we found that CD4 T cell responses in WT mice were primarily restricted to the I-A class II molecule, whereas DM(-/-) mice recognize peptides in the context of I-E. The observed shift in isotype-restriction appeared to be due in part to a modification in the peripheral CD4 T cell repertoire available for peptide recognition.