Regional and Chronological Variation of Chemosensory Dysfunction in COVID-19: a Meta-Analysis.

BACKGROUND: Olfactory and gustatory dysfunction are frequently reported in patients with coronavirus disease 2019 (COVID-19). However, the reported prevalence of olfactory and/or gustatory dysfunction varies widely, and the reason for the inter-study differences is unclear. Hence, in this meta-analysis, we performed subgroup analyses to investigate the factors that contribute to the inter-study variability in the prevalence of olfactory and gustatory dysfunction. METHODS: Out of 943 citations, we included 55 eligible studies with 13,527 patients with COVID-19 for a meta-analysis. Calculating the data extracted from each study, the weighted summary prevalence of olfactory and gustatory dysfunction was estimated using a Freeman-Tukey transformation with models based on random-effects assumptions. A meta-analysis of variance compared the prevalence of olfactory and gustatory dysfunction according to regional, chronological, demographic, and methodologic factors, respectively. RESULTS: The overall pooled prevalence rates of olfactory and gustatory dysfunction were 51.4% and 47.5%, respectively, in the random-effect model. In subgroup analyses, the prevalence rates of olfactory and gustatory dysfunction were significantly different among four geographical regions (both P < 0.001, respectively). Although the prevalence rates of olfactory and gustatory dysfunction did not significantly differ according to the time of enrollment, the subgroup analyses including only studies from the same geographical region (Europe) revealed a significant difference in olfactory dysfunction according to the time of enrollment. CONCLUSION: The regional and chronological differences in the prevalence rates of olfactory and gustatory dysfunctions partly explain the wide inter-study variability.

Lumbosacral and thoracolumbosacral cerebrospinal fluid volume changes in neonates, infants, children, and adolescents: A retrospective magnetic resonance imaging study.

BACKGROUND: The volume of cerebrospinal fluid can affect the pharmacokinetics and pharmacodynamics of local anesthetics for spinal anesthesia and other intrathecal medications. AIMS: The objective of this study was to estimate the lumbosacral cerebrospinal fluid volume and thoracolumbosacral cerebrospinal fluid volume using magnetic resonance images in pediatric patients from neonates and infants to adolescents. METHODS: Spinal magnetic resonance images of 500 pediatric patients (age <18 years) were reviewed. The lumbosacral cerebrospinal fluid volumes of 418 patients and thoracolumbosacral cerebrospinal fluid volumes of 248 patients were measured. The relationship between cerebrospinal fluid volumes and age, height, and weight were evaluated. The lumbosacral and thoracolumbosacral cerebrospinal fluid volumes per weight were calculated to elucidate developmental changes. RESULTS: The lumbosacral and thoracolumbosacral cerebrospinal fluid volumes showed linear correlations with height (r2  = 0.730 and r2  = 0.661, respectively), whereas they showed curvilinear correlations with age (r2  = 0.752 and r2  = 0.717, respectively) and weight (r2  = 0.734 and r2  = 0.734, respectively). The mean lumbosacral cerebrospinal fluid volume per weight (mL/kg) was 0.85 (standard deviation [SD]: 0.19, 95% confidence interval [CI]: 0.81-0.90) in neonates and infants, 0.86 (SD: 0.22, 95% CI: 0.83-0.89) in toddlers and preschoolers, 0.71 (SD: 0.26, 95% CI: 0.66-0.76) in schoolers, and 0.54 (SD: 0.20, 95% CI: 0.49-0.60) in adolescents. The mean thoracolumbosacral cerebrospinal fluid volume per weight (mL/kg) was 1.95 (SD: 0.37, 95% CI: 1.86-2.04) in neonates and infants, 1.82 (SD: 0.41, 95% CI: 1.75-1.88) in toddlers and preschoolers, 1.38 (SD: 0.40, 95% CI: 1.23-1.52) in schoolers, and 0.99 (SD: 0.34, 95% CI: 0.45-1.53) in adolescents. CONCLUSION: The lumbosacral and thoracolumbosacral cerebrospinal fluid volumes in pediatric patients were much smaller than previously presented values, showing linear correlations with height, and demonstrate curvilinear correlations with age and weight.

Genetic Load of Alternations of Transcription Factor Genes in Non-Syndromic Deafness and the Associated Clinical Phenotypes: Experience from Two Tertiary Referral Centers.

Sensorineural hearing loss is one of the most common inherited sensory disorders. Functional classifications of deafness genes have shed light on genotype- and mechanism-based pharmacological approaches and on gene therapy strategies. In this study, we characterized the clinical phenotypes and genotypes of non-syndromic deafness caused by transcription factor (TF) gene variants, one of the functional classifications of genetic hearing loss. Of 1280 probands whose genomic DNA was subjected to molecular genetic testing, TF genes were responsible for hearing loss in 2.6%. Thirty-three pathogenic variants, including nine novel variants, accounting for non-syndromic deafness were clustered in only four TF genes (POU3F4, POU4F3, LMX1A, and EYA4), which is indicative of a narrow molecular etiologic spectrum of TF genes, and the functional redundancy of many other TF genes, in the context of non-syndromic deafness. The audiological and radiological characteristics associated with the four TF genes differed significantly, with a wide phenotypic spectrum. The results of this study reveal the genetic load of TF gene alterations among a cohort with non-syndromic hearing loss. Additionally, we have further refined the clinical profiles associated with TF gene variants as a basis for a personalized, genetically tailored approach to audiological rehabilitation.

Effects of in vivo repositioning of slim modiolar electrodes on electrical thresholds and speech perception.

The slim modiolar electrode has been reported to ensure better modiolar proximity than previous conventional perimodiolar electrodes and consistently high scala tympani localization. Nonetheless, variability in modiolar proximity exists even among slim modiolar electrodes, still leaving room for further improvement of modiolar proximity, which may positively affect functional outcomes. Given this, the pull-back maneuver was reported to increase the modiolar proximity of slim modiolar electrodes in a cadaveric study, but in vivo repositioning effects remain to be established. Here we identified that the pull-back maneuver led to better modiolar proximity than conventional insertion while maintaining a similar angular insertion depth. Notably, the reduced electrode-modiolus distance from the pull-back maneuver was associated with significantly lower impedances across electrodes postoperatively as well as reduced intraoperative electrophysiological thresholds than conventional insertion. Among adult cochlear implant recipients, this maneuver resulted in significantly better sentence recognition scores at three months postoperatively when compared to those with a conventional insertion; however, this benefit was not observed at later intervals. Collectively, slim modiolar electrodes with the pull-back maneuver further enhance the modiolar proximity, possibly leading to better open-set sentence recognition, at least in the early postoperative stage.