Lobe specificity of iron binding to transferrin modulates murine erythropoiesis and iron homeostasis.

Transferrin, the major plasma iron-binding molecule, interacts with cell-surface receptors to deliver iron, modulates hepcidin expression, and regulates erythropoiesis. Transferrin binds and releases iron via either or both of 2 homologous lobes (N and C). To test the hypothesis that the specificity of iron occupancy in the N vs C lobe influences transferrin function, we generated mice with mutations to abrogate iron binding in either lobe (TfN-bl or TfC-bl). Mice homozygous for either mutation had hepatocellular iron loading and decreased liver hepcidin expression (relative to iron concentration), although to different magnitudes. Both mouse models demonstrated some aspects of iron-restricted erythropoiesis, including increased zinc protoporphyrin levels, decreased hemoglobin levels, and microcytosis. Moreover, the TfN-bl/N-bl mice demonstrated the anticipated effect of iron restriction on red cell production (ie, no increase in red blood cell [RBC] count despite elevated erythropoietin levels), along with a poor response to exogenous erythropoietin. In contrast, the TfC-bl/C-bl mice had elevated RBC counts and an exaggerated response to exogenous erythropoietin sufficient to ameliorate the anemia. Observations in heterozygous mice further support a role for relative N vs C lobe iron occupancy in transferrin-mediated regulation of iron homeostasis and erythropoiesis.

Cochlear implantation in children with single-sided deafness under the age of 5 years: a review of current literature.

PURPOSE OF REVIEW: Here we explore the current literature on cochlear implantation of pediatric patients under the age of 5 years with single-sided deafness (SSD). RECENT FINDINGS: Single-sided deafness has been noted to cause developmental delays in speech, language, and cognition because of loss of binaural hearing. Currently, cochlear implantation is the only intervention capable of restoring binaural hearing for pediatric patients with SSD. Young children have been shown to have the greatest neuroplasticity of the auditory cortex before 4 years of age. Currently, only children over the age of 5 years are approved by the United States Food and Drug Administration (FDA) to undergo cochlear implantation for SSD. Cochlear implantation for SSD in patients under the age of 5 years has been performed on a limited basis and has been shown to have excellent results. SUMMARY: Cochlear implantation is a well tolerated and effective treatment for pediatric patients under the age of 5 years with SSD. Receiving cochlear implantation under the age of 5 years is critical for child development as neuroplasticity decreases after this age.

Carotid-Threatening Penetrating Oropharyngeal Trauma in a Pediatric Patient: A Case Report and Literature Review.

Penetrating oropharyngeal injury is a relatively common occurrence in pediatric patients; however, cases involving close proximity to critical vascular structures, such as the internal carotid artery (ICA), are exceedingly rare and pose significant risks. This case report describes a seven-year-old male who sustained penetrating oropharyngeal trauma with startling proximity to the ICA after being pushed into a locker with a pencil in his mouth. Initial evaluation showed the wooden pencil protruding from the soft palate without active bleeding. CT angiography revealed that it was less than 1 mm from the left ICA, with no signs of extravasation or dissection. The pencil was removed atraumatically under ketamine sedation, and the puncture site was irrigated without complications. In patients presenting with penetrating oropharyngeal trauma, injury to the internal carotid or adjacent vessels with possible resulting extravasation or dissection should be considered. This is a single case report accompanied by a literature review.

Acute Onset of Delayed Facial Nerve Paralysis After an Uncomplicated Total Parotidectomy for an Oncocytoma.

Facial nerve injury is one of the most substantial potential sequelae of parotid surgery. Pulling, stretching, and otherwise disturbing the facial nerve during parotid surgery can lead to post-surgical neural paresis and consequential deficits in facial movement. Furthermore, transection of the main facial nerve trunk or its branches, either purposeful or incidental, can lead to complete paralysis of the related facial musculature. Facial nerve injury is often diagnosed immediately post-operatively as evident by deficits in ipsilateral facial motion on examination of the patient in the recovery unit or, at most, by one week post-operatively. Although delayed onset facial nerve paralysis is seen in traumatic injury and otologic surgery, it is uncommon that facial nerve paralysis presents late after parotid surgery in the absence of hematoma development, viral reactivation, or secondary insult. Here, we present the case of a 70-year-old man developing a delayed acute onset of hemi-facial paralysis 12 days after right-sided total parotidectomy for an oncocytoma; a facial nerve examination done immediately post-operatively and at the one-week post-operative follow-up was found to be normal. The patient was treated with two courses of high-dose oral steroids with close-to-complete resolution.

Otolaryngology Department and Society Leadership: Evaluation of Diversity in a Nationwide Study.

OBJECTIVES/HYPOTHESIS: Diversity in medicine positively influences healthcare delivery. As we aim to make otolaryngology more diverse, it is essential to analyze our current leadership. STUDY DESIGN: Observational study. METHODS: A total of 262 department chairs and chiefs, residency program directors, and assistant and associate directors from 117 otolaryngology residency programs as well as 92 society leaders from nine otolaryngology national societies from 2010 to 2020 in the United States are included in this study. The position, academic rank, name, gender, inferred race (based on name and image), and h-index are collected and recorded from publicly available data. Fisher's exact test, unpaired t tests, and analysis of variance tests are used. RESULTS: The ethno-racial breakdown of all otolaryngology residency leaders is as follows: 78.63% non-Hispanic (NH) White, 16.03% NH Asian, 2.29% Middle Eastern, 1.91% NH Black, and 1.15% Latinx. Male gender is found to be a predictor of full professorship title (P < .0001) with an odds ratio (OR) of 4.066. NH White male is also a predictor of full professorship (P < .0001) with an OR 3.05. When comparing h-index, males and females differ (P < .0001) across all residency leadership positions. There is a higher h-index among full professors compared to non-full professors (P < .0001). The ethno-racial breakdown of society leaders is 84% NH White, 11% NH Asian, 2% NH Black, 2% Latinx, and 1% Middle Eastern. CONCLUSIONS: In conclusion, otolaryngology leadership has an under-representation of women and certain ethno-racial groups. Continued efforts should be made to diversify our specialty's leadership. LEVEL OF EVIDENCE: NA Laryngoscope, 132:1729-1737, 2022.

FDA MAUDE database analysis of titanium middle ear prosthesis.

PURPOSE: Partial ossicular replacement (PORP) and total ossicular replacement prostheses (TORP) are used to restore ossicular chain function. Despite favorable auditory outcomes, these interventions have associated risks and complications. This study examines the FDA MAUDE database for ossicular chain prosthesis adverse events to highlight complications, interventions, and root cause analysis (RCA) findings. MATERIALS AND METHODS: The MAUDE database was searched for Medical Device Reports (MDRs) relating to PORPs and TORPs from 2010 to 2020. MDR event descriptions were reviewed, and adverse events were identified as a device issue, patient issue, and/or packaging issue that occurred intraoperatively or postoperatively. RESULTS: Our search identified 70 MDRs which included 110 reported adverse events. Events consisted of 63 device issues, often due to device breaks and displacements, 39 patient issues, including common complaints of hearing loss and erosion, and 8 packaging issues. When comparing PORPs and TORPs, TORPs had more reported device issues whereas PORPs had more packaging issues. Intraoperative device issues were commonly resolved by completing the procedure with a backup device and most postoperative device issues required additional surgery. For devices returned to the manufacturer, RCA determined that most breaks were caused by modification and/or mishandling or that the product met specifications with an undetermined cause for the break. CONCLUSION: Device issues were the most common adverse events and frequently required subsequent intervention. Displacement occurred more often with TORPs and was associated with changes in hearing or erosion. The findings of this study are purely descriptive and may not have direct clinical relevance.