The audiometric and mechanical effects of partial ossicular discontinuity

Objectives: Ossicular discontinuity may be complete, with no contact between the disconnected ends, or partial, where normal contact at an ossicular joint or along a continuous bony segment of an ossicle is replaced by soft tissue or simply by contact of opposing bones. Complete ossicular discontinuity typically results in an audiometric pattern of a large, flat conductive hearing loss. In contrast, in cases where otomicroscopy reveals a normal external ear canal and tympanic membrane, high-frequency conductive hearing loss has been proposed as an indicator of partial ossicular discontinuity. Nevertheless, the diagnostic utility of high-frequency conductive hearing loss has been limited due to gaps in previous research on the subject, and clinicians often assume that an audiogram showing high-frequency conductive hearing loss is flawed. This study aims to improve the diagnostic utility of high-frequency conductive hearing loss in cases of partial ossicular discontinuity by (1) making use of a control population against which to compare the audiometry of partial ossicular discontinuity patients and (2) examining the correlation between high-frequency conductive hearing loss and partial ossicular discontinuity under controlled experimental conditions on fresh cadaveric temporal bones. Furthermore, ear-canal measurements of umbo velocity and wideband acoustic immittance measurements were investigated to determine the usefulness regarding diagnosis of ossicular discontinuity. Design: The authors analyzed audiograms from 66 patients with either form of surgically confirmed ossicular discontinuity and no confounding pathologies. The authors also analyzed umbo velocity (n = 29) and power reflectance (n = 12) measurements from a subset of these patients. Finally, the authors performed experiments on six fresh temporal bone specimens to study the differing mechanical effects of complete and partial discontinuity. The mechanical effects of these lesions were assessed via laser Doppler measurements of stapes velocity. In a subset of the specimen (n = 4), wideband acoustic immittance measurements were also collected. Results: (1) Calculations comparing the air–bone gap (ABG) at high and low frequencies show that when high-frequency ABGs are larger than low-frequency ABGs, the surgeon usually reported soft-tissue bands at the point of discontinuity. However, in cases with larger low-frequency ABGs and flat ABGs across frequencies, some partial discontinuities as well as complete discontinuities were reported. (2) Analysis of umbo velocity and power reflectance (calculated from wideband acoustic immittance) in patients reveal no significant difference across frequencies between the two types of ossicular discontinuities. (3) Temporal bone experiments reveal that partial discontinuity results in a greater loss in stapes velocity at high frequencies when compared with low frequencies, whereas with complete discontinuity, large losses in stapes velocity occur at all frequencies. Conclusion: The clinical and experimental findings suggest that when encountering larger ABGs at high frequencies when compared with low frequencies, partial ossicular discontinuity should be considered in the differential diagnosis

Assessment of Sudden Sensorineural Hearing Loss After COVID-19 Vaccination

Importance: Emerging reports of sudden sensorineural hearing loss (SSNHL) after COVID-19 vaccination within the otolaryngological community and the public have raised concern about a possible association between COVID-19 vaccination and the development of SSNHL. Objective: To examine the potential association between COVID-19 vaccination and SSNHL. Design, Setting, and Participants: This cross-sectional study and case series involved an up-to-date population-based analysis of 555 incident reports of probable SSNHL in the Centers for Disease Control and Prevention Vaccine Adverse Events Reporting System (VAERS) over the first 7 months of the US vaccination campaign (December 14, 2020, through July 16, 2021). In addition, data from a multi-institutional retrospective case series of 21 patients who developed SSNHL after COVID-19 vaccination were analyzed. The study included all adults experiencing SSNHL within 3 weeks of COVID-19 vaccination who submitted reports to VAERS and consecutive adult patients presenting to 2 tertiary care centers and 1 community practice in the US who were diagnosed with SSNHL within 3 weeks of COVID-19 vaccination. Exposures: Receipt of a COVID-19 vaccine produced by any of the 3 vaccine manufacturers (Pfizer-BioNTech, Moderna, or Janssen/Johnson and Johnson) used in the US. Main Outcomes and Measures: Incidence of reports of SSNHL after COVID-19 vaccination recorded in VAERS and clinical characteristics of adult patients presenting with SSNHL after COVID-19 vaccination. Results: A total of 555 incident reports in VAERS (mean patient age, 54 years [range, 15-93 years]; 305 women [55.0%]; data on race and ethnicity not available in VAERS) met the definition of probable SSNHL (mean time to onset, 6 days [range, 0-21 days]) over the period investigated, representing an annualized incidence estimate of 0.6 to 28.0 cases of SSNHL per 100000 people per year. The rate of incident reports of SSNHL was similar across all 3 vaccine manufacturers (0.16 cases per 100000 doses for both Pfizer-BioNTech and Moderna vaccines, and 0.22 cases per 100 000 doses for Janssen/Johnson and Johnson vaccine). The case series included 21 patients (mean age, 61 years [range, 23-92 years]; 13 women [61.9%]) with SSNHL, with a mean time to onset of 6 days (range, 0-15 days). Patients were heterogeneous with respect to clinical and demographic characteristics. Preexisting autoimmune disease was present in 6 patients (28.6%). Of the 14 patients with posttreatment audiometric data, 8 (57.1%) experienced improvement after receiving treatment. One patient experienced SSNHL 14 days after receiving each dose of the Pfizer-BioNTech vaccine. Conclusions and Relevance: In this cross-sectional study, findings from an updated analysis of VAERS data and a case series of patients who experienced SSNHL after COVID-19 vaccination did not suggest an association between COVID-19 vaccination and an increased incidence of hearing loss compared with the expected incidence in the general population

Translation and Cross-Cultural Adaptation of English Version of Kiddy-KINDL to Filipino Language in Assessing the Children\u27s Health-Related Quality of Life (CHRQoL)

Background: Children\u27s health-related quality of life (CHRQoL) involves a child\u27s aim, expectations, standards, or concerns regarding overall health and its domains. The Kiddy-KINDL questionnaire is a tool to measure CHRQoL from information directly derived from children. It has been translated to various languages, except Filipino. This study would provide Filipino healthcare professionals with another functional tool for pediatric evaluation. Objective: To translate the English version of Kiddy-KINDL to Filipino and to determine its validity, test-retest reliability, and internal consistency of the Kiddy-KINDL in assessing the children\u27s health-related quality of life (CHRQoL). Methods: The study involved 3 Phases: Translation, Pilot Testing, and Reliability Phase. The English version of Kiddy-KINDL was cross-culturally adapted and translated into Filipino through a forward and backward translation process. Face validity was performed with 40 participants during the pilot testing phase. Test-retest reliability testing was performed with a total of 116 pairs of children, ages four to six, and their guardian living in Metropolitan Manila. Results: In phases 1 and 2, there were a total of 5 versions before the final Filipino version was considered acceptable. In phase 3, the test-retest reliability score of each dimension ranged from 0.18 to 0.98. The total reliability scores were 0.77 and 0.98 for adults and children, respectively. The internal consistency score was found to be acceptable in both questionnaires. Conclusion: The Filipino-translated Kiddy-KINDL has acceptable face validity results, test-retest reliability, and internal consistency scores

Expression, Purification, Structural and Functional Analysis of SycB: A Type Three Secretion Chaperone From Yersinia Enterocolitica

In Yersinia enterocolitica biovar 1B, a genome encoded TTSS designated as Ysa-Ysp system is used for virulence. SycB is an annotated chaperone to this system. SycB is soluble in presence of translocator YspC. SycB and its truncated form (DSycB(1–114)) exist as dimers. YspC forms a 1:1 complex with SycB. Homology model of SycB shows a flexible N-terminal may be required for solubility and dimerization; and concave core formed by antiparallel helices of TPRs. Far UV CD spectra confirm that SycB is predominantly alpha helical. Near UV CD spectra show that SycB has tertiary structure at pH 7.2 (native folded protein), which disappears at pH 5 (molten globule) and SycB releases YspC at pH 5. SycB has a cooperative melting behavior. At pH 7.2, SycB shows solvent accessible hydrophobic patches. Concave core in the model exhibits ANS binding within FRET distance of tyrosines in the TPR, allowing a range of interaction of SycB with its ligand