Reconstruction of the External Auditory Canal for Spontaneous Temporomandibular Joint Herniation.

Spontaneous herniation of the temporomandibular joint into the external auditory canal is rare and generally results from inflammation or trauma but is rarely documented as a result of osteoradionecrosis. We report the novel surgical management of TMJ herniation by reconstructing the anterior EAC using conchal cartilage and a vascularized pedicled muscle flap in two patients. At follow-up, both had healing of the ear canal and TM without any evidence of joint herniation, with improved QOL and hearing. TMJ herniation due to an anterior EAC defect from osteoradionecrosis or trauma can be reconstructed with a cartilage graft and vascularized fascia flap. Laryngoscope, 2024.

Rapid imaging of intravenous gadolinium-based contrast agent (GBCA) entering ventricular cerebrospinal fluid (CSF) through the choroid plexus in healthy human subjects.

BACKGROUND: Pathways for intravenously administered gadolinium-based-contrast-agents (GBCAs) entering cerebrospinal-fluid (CSF) circulation in the human brain are not well-understood. The blood-CSF-barrier (BCSFB) in choroid-plexus (CP) has long been hypothesized to be a main entry-point for intravenous-GBCAs into CSF. Most existing studies on this topic were performed in animals and human patients with various diseases. Results in healthy human subjects are limited. Besides, most studies were performed using MRI methods with limited temporal resolution and significant partial-volume effects from blood and CSF. METHODS: This study employs the recently developed dynamic-susceptibility-contrast-in-the-CSF (cDSC) MRI approach to measure GBCA-distribution in the CSF immediately and 4 h after intravenous-GBCA administration in healthy subjects. With a temporal resolution of 10 s, cDSC MRI can track GBCA-induced CSF signal changes during the bolus phase, which has not been investigated previously. It employs a long echo-time (TE = 1347 ms) to suppress tissue and blood signals so that pure CSF signal is detected with minimal partial-volume effects. GBCA concentration in the CSF can be estimated from cDSC MRI. In this study, cDSC and FLAIR MRI were performed immediately and 4 h after intravenous GBCA administration in 25 healthy volunteers (age 48.9 ± 19.5 years; 14 females). Paired t-tests were used to compare pre-GBCA and post-GBCA signal changes, and their correlations with age were evaluated using Pearson-correlation-coefficients. RESULTS: At ~ 20 s post-GBCA, GBCA-induced cDSC signal changes were detected in the CSF around CP (ΔS/S = - 2.40 ± 0.30%; P < .001) but not in the rest of lateral ventricle (LV). At 4 h, significant GBCA-induced cDSC signal changes were observed in the entire LV (ΔS/S = - 7.58 ± 3.90%; P = .002). FLAIR MRI showed a similar trend. GBCA-induced CSF signal changes did not correlate with age. CONCLUSIONS: These results provided direct imaging evidence that GBCAs can pass the BCSFB in the CP and enter ventricular CSF immediately after intravenous administration in healthy human brains. Besides, our results in healthy subjects established a basis for clinical studies in brain diseases exploiting GBCA-enhanced MRI to detect BCSFB dysfunction.

Superior Canal Dehiscence and the Risk of Additional Dehiscences: A Retrospective CT Cohort Study.

OBJECTIVE: Determine if superior canal dehiscence (SCD) found on flat-panel CT increases the risk for other defects in the otic capsule. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary care center. PATIENTS: One hundred ears (50 with SCD and 50 matched controls without SCD). INTERVENTIONS: Flat-panel CT imaging. MAIN OUTCOME MEASURES: (1) Prevalence of other dehiscences in SCD ears, (2) dehiscences in controls, and (3) otic capsule thickness in other reported dehiscence locations (cochlea-carotid, lateral semicircular canal [SCC] and mastoid, facial nerve-lateral SCC, vestibular aqueduct, posterior SCC-jugular bulb, posterior SCC-posterior fossa). Between-group comparisons were considered significant at p < 0.007 after applying the Bonferroni correction for multiple comparisons. RESULTS: Not including the SCD, there was a mean of 0.04 additional dehiscences in the SCD group (n = 2/50, 4%) and 0.04 non-SCD dehiscences in the controls (n = 2/50, 4%, p > 0.007). In the SCD group, there was one dehiscence between the cochlea and carotid artery and one between the posterior SCC and posterior fossa. The control group had one enlarged vestibular aqueduct and one dehiscence between the facial nerve and lateral SCC. As a group, SCD ears had wider vestibular aqueducts (0.68 ± 0.20 vs 0.51 ± 0.30 mm, p < 0.007) and thinner bone between the posterior SCC and posterior fossa (3.12 ± 1.43 vs 4.34 ± 1.67 mm, p < 0.007). The bone between the facial nerve and lateral SCC was thicker in SCD ears (0.77 ± 0.23 vs 0.55 ± 0.27 mm, p < 0.007) and no different for cochlea-carotid, and lateral SCC and mastoid (p > 0.007). CONCLUSIONS: SCD does not increase the likelihood of a second dehiscence in the same otic capsule. SCD patients may have congenitally thinner otic capsule bones compared to controls, particularly near the posterior SCC, where the vestibular aqueduct may be enlarged.

Popularizing Surgical Cures: Walter Dandy and the Vestibular Neurectomy for Menière's Disease at the Johns Hopkins Hospital.

OBJECTIVES: To uncover the context that allowed for the vestibular neurectomy to grow in favor and practice at the Johns Hopkins Hospital in the early 20th century, and the reasons for its broad abandonment since. METHODS: The Walter E. Dandy (1905-1946) and Samuel J. Crowe collections (1905-1920) at the Alan Mason Chesney Medical Archives were reviewed, as well as the Samuel J. Crowe and Stacy Guild Temporal Bone Collection. RESULTS: Speculation on the etiology of Menière's disease (MD) has been countless, as have the medical and surgical interventions aimed at treating it. At the Johns Hopkins Hospital, Walter Dandy popularized the neurectomy for MD and performed 692 procedures from 1924 to 1946, believing it to be a curative therapy for vertigo. When he later modified the procedure from a total cranial nerve section to a partial vestibular neurectomy preserving auditory function, surgical candidacy expanded to include nearly any patient with vestibular symptoms. After his passing, trainees' attention shifted to traumatic injuries, likely influenced by WWII. This left the procedure scarcely used until third parties rekindled interest decades later. CONCLUSIONS: Neurectomy as the preferential treatment for MD at the Johns Hopkins Hospital was not driven by pure scientific reasoning but was rather contingent on historical context and sponsorship by a prominent figure like Walter Dandy. Appreciation of MD's natural history has since curtailed the favorability of destructive procedures in preference for conservative management.

SVPath: A Deep Learning Tool for Analysis of Stria Vascularis from Histology Slides.

INTRODUCTION: The stria vascularis (SV) may have a significant role in various otologic pathologies. Currently, researchers manually segment and analyze the stria vascularis to measure structural atrophy. Our group developed a tool, SVPath, that uses deep learning to extract and analyze the stria vascularis and its associated capillary bed from whole temporal bone histopathology slides (TBS). METHODS: This study used an internal dataset of 203 digitized hematoxylin and eosin-stained sections from a normal macaque ear and a separate external validation set of 10 sections from another normal macaque ear. SVPath employed deep learning methods YOLOv8 and nnUnet to detect and segment the SV features from TBS, respectively. The results from this process were analyzed with the SV Analysis Tool (SVAT) to measure SV capillaries and features related to SV morphology, including width, area, and cell count. Once the model was developed, both YOLOv8 and nnUnet were validated on external and internal datasets. RESULTS: YOLOv8 implementation achieved over 90% accuracy for cochlea and SV detection. nnUnet SV segmentation achieved a DICE score of 0.84-0.95; the capillary bed DICE score was 0.75-0.88. SVAT was applied to compare both the ears used in the study. There was no statistical difference in SV width, SV area, and average area of capillary between the two ears. There was a statistical difference between the two ears for the cell count per SV. CONCLUSION: The proposed method accurately and efficiently analyzes the SV from temporal histopathology bone slides, creating a platform for researchers to understand the function of the SV further.

A Deep Learning Framework for Analysis of the Eustachian Tube and the Internal Carotid Artery.

OBJECTIVE: Obtaining automated, objective 3-dimensional (3D) models of the Eustachian tube (ET) and the internal carotid artery (ICA) from computed tomography (CT) scans could provide useful navigational and diagnostic information for ET pathologies and interventions. We aim to develop a deep learning (DL) pipeline to automatically segment the ET and ICA and use these segmentations to compute distances between these structures. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary referral center. METHODS: From a database of 30 CT scans, 60 ET and ICA pairs were manually segmented and used to train an nnU-Net model, a DL segmentation framework. These segmentations were also used to develop a quantitative tool to capture the magnitude and location of the minimum distance point (MDP) between ET and ICA. Performance metrics for the nnU-Net automated segmentations were calculated via the average Hausdorff distance (AHD) and dice similarity coefficient (DSC). RESULTS: The AHD for the ET and ICA were 0.922 and 0.246 mm, respectively. Similarly, the DSC values for the ET and ICA were 0.578 and 0.884. The mean MDP from ET to ICA in the cartilaginous region was 2.6 mm (0.7-5.3 mm) and was located on average 1.9 mm caudal from the bony cartilaginous junction. CONCLUSION: This study describes the first end-to-end DL pipeline for automated ET and ICA segmentation and analyzes distances between these structures. In addition to helping to ensure the safe selection of patients for ET dilation, this method can facilitate large-scale studies exploring the relationship between ET pathologies and the 3D shape of the ET.

Case Presentation: Functional Assessment of a CASR Variant Identified in a Patient with Hypercalcaemia Confirms Familial Hypocalciuric Hypercalcaemia in the Patient and a Sister Previously Misdiagnosed with Primary Hyperparathyroidism.

Background: Primary hyperparathyroidism (PHPT) and familial hypocalciuric hypercalcaemia (FHH) are common causes of hypercalcaemia. Patients are mostly asymptomatic in the case of FHH and often so in the case of PHPT. In addition, biochemical parameters show considerable overlap, making differential diagnosis difficult. Genetic screening for inactivating variants in the calcium-sensing receptor (CASR) gene that are causative of FHH assists with the diagnosis since such variants are not generally associated with PHPT. However, novel CASR variants must undergo functional assessment before they can be definitively assigned a causative role in FHH. Case Presentations. We describe a 73-year-old female (patient A) who presented with mild parathyroid hormone (PTH)-dependent hypercalcaemia and a history of osteoporosis. Family history revealed that her sister (patient B) had presented a decade earlier with symptoms of PHPT including a history of mild hypercalcaemia and multiple renal calculi, prompting parathyroid surgery. However, a subtotal parathyroidectomy did not resolve her hypercalcaemia long term. On this basis, genetic screening was performed on patient A. This identified a heterozygous variant in the CASR, NM_000388.4:c.T101C: p.Leu34Pro (L34P). Functional analysis showed that the L34P variant was unable to produce mature, dimerized receptor and did not respond to Ca++ ions. Adopting American College of Medical Genetics-based guidelines, the variant was classified as 'Pathogenic (II)'. Patient B was subsequently found to carry the L34P variant heterozygously, confirming a diagnosis of FHH, not PHPT. Conclusion: This study shows the importance of examining patient's family history in providing clues to the diagnosis in isolated cases of hypercalcaemia. In this case, history of a sister's unsuccessful parathyroidectomy prompted genetic screening in a patient who might otherwise have undergone inappropriate parathyroid surgery. Screening detected an inactivating CASR variant, firming up a diagnosis of FHH. These studies reaffirm the requirement for functionally assessing novel CASR variants prior to assigning causality to FHH.

Patterns of Signal Intensity in CISS MRI of the Inner Ear and Eye.

BACKGROUND: Constructive interference in steady state (CISS) is a gradient echo magnetic resonance imaging (MRI) pulse sequence that provides excellent contrast between cerebrospinal fluid and adjacent structures but is prone to banding artifacts due to magnetic field inhomogeneities. We aimed to characterize artifacts in the inner ear and eye. METHODS: In 30 patients (60 ears/eyes) undergoing CISS sequence MRI, nine low-signal intensity regions were identified in the inner ear and compared to temporal bone histopathology. The number and angle of bands across the eye were examined. RESULTS: In the cochlea, all ears had regions of low signal corresponding to anatomy (modiolus (all), spiral lamina (n = 59, 98.3%), and interscalar septa (n = 50, 83.3%)). In the labyrinth, the lateral semicircular canal crista (n = 42, 70%) and utricular macula (n = 47, 78.3%) were seen. Areas of low signal in the vestibule seen in all ears may represent the walls of the membranous utricle. Zero to three banding artifacts were seen in both eyes (right: 96.7%, mean 1.5; left: 93.3%, mean 1.3). CONCLUSION: Low signal regions in the inner ear on CISS sequences are common and have consistent patterns; most in the inner ear represent anatomy, appearing blurred due to partial volume averaging. Banding artifacts in the eye are more variable.

Historical Therapies for Suspected Autonomic Dysregulation in Meniere's Disease.

OBJECTIVE: This narrative review examines how speculative belief that the autonomic nervous system causes Meniere's Disease (MD) led otolaryngologists to adopt invasive surgical procedures and medical treatments still offered today. DATA SOURCES: Google Scholar, PubMed. REVIEW METHODS: A comprehensive literature review (1860-2022) was performed using the terms "Meniere AND (sympathetic OR sympathectomy OR vasomotor OR cervical ganglion)," returning 5360 items. All abstracts were briefly reviewed, relevant publications selected for further study, and key articles discussed by all authors. As it became clear that betahistine was related to the historical narrative, an additional search was performed using "Betahistine AND Meniere AND (vasomotor OR sympathetic OR sympathectomy OR cervical ganglion OR autonomic)," which yielded 336 results. RESULTS: In the 19th and 20th centuries, growing knowledge of human anatomy led the scientific community to speculate that autonomic dysregulation caused many medical conditions. Excessive sympathetic mediated vasomotor changes were thought to cause hypertension, ischemia, and tissue damage. Clinicians applied the hypothesis to MD, assigning the sympathetic nervous system responsible for vertigo secondary to paroxysmal vasospasm and for hearing loss to poor cochlear nutrition. Despite limited animal experiments and isolated clinical observations, otolaryngologists performed sympathectomies, and, in the 1970s, replaced the procedure with betahistine as an alternative medical treatment. CONCLUSION: Premature excitement about a plausible hypothesis led to unnecessary and unwarranted operations. Despite absent evidence of sympathetic overactivation in MD, surgeons eagerly adopted sympathectomies, and later betahistine. Rigorous evaluation of the validity of these treatment practices is needed. LEVEL OF EVIDENCE: 5 Laryngoscope, 134:535-542, 2024.

Association Between Retinal Pathology and Hearing in Older Adults.

We investigated the association between retinal microvascular changes and hearing loss based on the hypothesis that both may result from shared microvascular pathology. Data from 536 older adults from the National Health and Nutritional Examination Survey 2005 to 2006 including sociodemographic and health characteristics, pure-tone hearing thresholds, and retinal pathologies were collected and analyzed. Associations between retinal and hearing pathologies were modeled with multivariable-adjusted linear regressions. 75% of participants had hearing loss and 15% of participants had retinopathy. The association between retinopathy, microaneurysms, and blot hemorrhages with better speech-frequency pure tone average was -2.81 (95% confidence interval [CI]: -5.72 to 0.10), -4.75 (95% CI: -8.73 to -0.78), and -5.34 (95% CI: -8.68 to -2.00), respectively. The presence of retinopathy, microaneurysms, and blot hemorrhages was inversely associated with hearing loss. Further studies are needed to better understand the potential relationship between microvascular pathologies of the eye and ear.

Longer duration entry mitigates nystagmus and vertigo in 7-Tesla MRI.

Introduction: Patients and technologists commonly describe vertigo, dizziness, and imbalance near high-field magnets, e.g., 7-Tesla (T) magnetic resonance imaging (MRI) scanners. We sought a simple way to alleviate vertigo and dizziness in high-field MRI scanners by applying the understanding of the mechanisms behind magnetic vestibular stimulation and the innate characteristics of vestibular adaptation. Methods: We first created a three-dimensional (3D) control systems model of the direct and indirect vestibulo-ocular reflex (VOR) pathways, including adaptation mechanisms. The goal was to develop a paradigm for human participants undergoing a 7T MRI scan to optimize the speed and acceleration of entry into and exit from the MRI bore to minimize unwanted vertigo. We then applied this paradigm from the model by recording 3D binocular eye movements (horizontal, vertical, and torsion) and the subjective experience of eight normal individuals within a 7T MRI. The independent variables were the duration of entry into and exit from the MRI bore, the time inside the MRI bore, and the magnetic field strength; the dependent variables were nystagmus slow-phase eye velocity (SPV) and the sensation of vertigo. Results: In the model, when the participant was exposed to a linearly increasing magnetic field strength, the per-peak (after entry into the MRI bore) and post-peak (after exiting the MRI bore) responses of nystagmus SPV were reduced with increasing duration of entry and exit, respectively. There was a greater effect on the per-peak response. The entry/exit duration and peak response were inversely related, and the nystagmus was decreased the most with the 5-min duration paradigm (the longest duration modeled). The experimental nystagmus pattern of the eight normal participants matched the model, with increasing entry duration having the strongest effect on the per-peak response of nystagmus SPV. Similarly, all participants described less vertigo with the longer duration entries. Conclusion: Increasing the duration of entry into and exit out of a 7T MRI scanner reduced or eliminated vertigo symptoms and reduced nystagmus peak SPV. Model simulations suggest that central processes of vestibular adaptation account for these effects. Therefore, 2-min entry and 20-s exit durations are a practical solution to mitigate vertigo and other discomforting symptoms associated with undergoing 7T MRI scans. In principle, these findings also apply to different magnet strengths.

Acoustic Noise Levels in High-field Magnetic Resonance Imaging Scanners.

7-Tesla (T) magnetic resonance imaging may allow for higher resolution images but may produce greater acoustic noise than 1.5- and 3-T scanners. We sought to characterize the intensity of acoustic noise from 7- versus 3-T scanners. A-weighted sound pressure levels from 5 types of pulse sequences used for brain and inner ear imaging in 3- and 7-T scanners were measured. Time-averaged sound level and maximum sound levels generated for each sequence were compared. Time-averaged sound levels exceeded 95 dB and reached maximums above 105 dB on the majority of 3- and 7-T scans. The mean time-averaged sound level and maximum sound level across pulse sequences were greater in 7- than 3-T (105.6 vs 91.4, P = .01; 114.0 vs. 96.5 dB, P < .01). 7- and 3-T magnetic resonance imaging scanners produce high levels of acoustic noise that exceed acceptable safety limits, emphasizing the need for active and passive noise protection.

Differential Volume Increase of Endolymphatic Compartments in Ménière's Disease Is Inversely Associated With Membrane Thickness.

OBJECTIVES: Our aim in this study was to characterize the morphology of the endolymphatic compartment on histopathology in individuals with Ménière's disease (MD) and to determine why hydrops of the saccule is more pronounced than that of other compartments of the inner ear in MD. METHODS: Temporal bones from 9 patients with idiopathic MD and from 10 individuals without MD/endolymphatic hydrops were examined. The inner ear fluid compartments in normal ears, and ears with MD were three-dimensionally reconstructed and their volume was calculated. The thickness of the membranes of the labyrinth was measured, and both ruptures of the membranes and patency of the utriculoendolymphatic (UEV; Bast's) valve were assessed. RESULTS: In ears with MD, the saccule and the cochlear duct were most frequently hydropic; the utricle was involved approximately half as frequently. In ears without MD, the Reissner's membrane and the membranous wall of the saccule were thinner than that of the utricle and of the lateral semicircular canal ( p < 0.01). The lateral semicircular canal did not show signs of hydrops. In all ears with MD in which the utricle exceeded the average volume of normals (6 of 12), the UEV was open or there was a rupture in the utricle. CONCLUSION: Increases in endolymphatic pressure may cause a primary swelling of the apical cochlear duct and saccule, both of which have relatively thin membranes. Hydrops in the utricle may occur less frequently because of a thicker wall, because of a functioning UEV, and when the saccule has already occupied most of the vestibular perilymphatic space.

Digenic Congenital Hypogonadotropic Hypogonadism Due to Heterozygous GNRH1 p.R31C and AMHR2 p.G445_L453del Variants.

A 28-year-old man with congenital hypogonadotropic hypogonadism (CHH) was found to be heterozygous for the GNRH1 p.R31C mutation, reported in the literature as pathogenic and dominant. The same mutation was found in his son at birth, but the testing of the infant at 64 days confirmed the hormonal changes associated with minipuberty. This led to further genetic sequencing of the patient and his son, which found a second variant, AMHR2 p.G445_L453del, in the heterozygous form, reported as pathogenic in the patient but not in his son. This suggests a digenic cause of the patient's CHH. Together, these mutations are postulated to contribute to CHH by the lack of anti-Müllerian hormone (AMH) signalling, leading to the impaired migration of gonadotrophin releasing hormone (GnRH) neurons, the lack of the AMH effect on GnRH secretion, and altered GnRH decapeptide with reduced binding to GnRH receptors. This led us to the conclusion that the observed GNRH1 mutation in the heterozygous state is not certain to be dominant or, at least, exhibits incomplete penetrance and variable expressivity. This report also emphasises the opportunity afforded by the time window of minipuberty in assessing the inherited genetic disorders of hypothalamic function.

Cochlear Aqueduct Morphology in Superior Canal Dehiscence Syndrome.

The cochlear aqueduct (CA) connects the scala tympani to the subarachnoid space and is thought to assist in pressure regulation of perilymph in normal ears, however, its role and variation in inner ear pathology, such as in superior canal dehiscence syndrome (SCDS), is unknown. This retrospective radiographic investigation compared CA measurements and classification, as measured on flat-panel computerized tomography, among three groups of ears: controls, n = 64; anatomic superior canal dehiscence without symptoms (SCD), n = 28; and SCDS, n = 64. We found that in a multinomial logistic regression adjusted for age, sex, and BMI, an increase in CA length by 1 mm was associated with a lower odds for being in the SCDS group vs. control (Odds ratio 0.760 p = 0.005). Hierarchical clustering of continuous CA measures revealed a cluster with small CAs and a cluster with large CAs. Another multinomial logistic regression adjusted for the aforementioned clinical covariates showed an odds ratio of 2.97 for SCDS in the small CA cluster as compared to the large (p = 0.004). Further, no significant association was observed between SCDS symptomatology-vestibular and/or auditory symptoms-and CA structure in SCDS ears. The findings of this study lend support to the hypothesis that SCDS has a congenital etiology.

Patulous Eustachian Tube Dysfunction Symptoms Following Balloon Dilation.

OBJECTIVE: Clinicians increasingly perform balloon dilation of the Eustachian tube (BDET) to treat obstructive Eustachian tube dysfunction (OETD) refractory to medical management. Reported complications have been limited and include patulous Eustachian tube dysfunction (PETD). This multicenter study investigates the incidence of PETD and associated factors. METHODS: Consecutive patients at three academic centers undergoing BDET (January 2014-November 2019) for OETD refractory to medical therapy were included. PETD was diagnosed by patient-reported symptoms of autophony of voice and/or breathing. Associated factors studied include age, sex, comorbidities, balloon size, duration of inflation, repeat BDET, and adjunctive procedures. RESULTS: BDET procedures (n = 295 Eustachian tubes) were performed on 182 patients. Mean age was 38.4 years (SD 21.0; range 7-78) and 41.2% were female. Twenty cases of PETD (6.8% of procedures; 9.3% of patients) occurred following BDET. Risk of PETD did not vary by institution, comorbidities, or adjunctive procedure. Age ≤18 years (adjusted risk ratio [RR] = 3.26; 95% confidence interval [CI]: 1.24, 8.54; p = 0.02), repeat BDET (RR = 3.26; 95% CI: 2.15, 4.96; p < 0.001), and severe preoperative Eustachian tube inflammation (RR = 2.83; 95% CI: 1.10, 7.28; p = 0.03) were associated with increased risk of developing PETD in the multivariable model. Most symptoms were reported as mild or intermittent. CONCLUSION: BDET caused PETD symptoms in approximately 7% of dilated Eustachian tubes in this study with increased risk for younger patients and those with severe inflammation or undergoing repeat dilations. Although most cases were self-limited, symptoms can persist. Awareness of risk factors may aid clinicians in limiting this complication. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:3152-3157, 2023.

Sex and Race Representation in Temporal Bone Histopathology Studies in the United States: A Systematic Review.

OBJECTIVES: The author's objective was to evaluate sex and race representation in temporal bone histopathology studies. DESIGN: PubMed, Embase, Cochrane, Web of Science, and Scopus were searched for studies written in English examining temporal bone histopathology specimens from U.S.-based institutions from January 1, 1947, to September 1, 2021. Two authors then performed "snowballing" by reviewing references from the initial search and included the studies that fulfilled the inclusion criteria. For each study, the following information was collected: publication details, study design, funding, institution from where temporal bone specimens were procured, number of study specimens, and donor demographical information. RESULTS: The authors found that out of 300 studies, 166 (55%) report sex while only 15 (5%) reported race information. Over the past 70 years, the ratio of studies reporting sex to those that do not has increased from 1.00 to 2.19 and the number of female temporal bone histopathology subjects relative to male has increased from 0.67 to 0.75. Over 90% of studies that do report this information feature participant racial compositions that do not reflect the diversity of the U.S. population. CONCLUSIONS: Studies of temporal bone histopathology often do not report participant sex or race. The reporting of participant sex and the inclusion of specimens from female donors have both increased over time. However, temporal bone histopathology study cohorts are not representative of the racial diversity of the U.S. population. The otolaryngology community must strive to build temporal bone histopathology libraries that are representative of the diverse U.S. population.

Vestibular Implantation Can Work Even After More Than 20 Years of Bilateral Vestibular Hypofunction.

OBJECTIVE: To determine whether prosthetic stimulation delivered via a vestibular implant can elicit artificial sensation of head movement despite long (23-yr) duration adult-onset ototoxic bilateral vestibular hypofunction (BVH). STUDY DESIGN: Case report. SETTING: Tertiary care center as part of a first-in-human clinical trial. PATIENTS: One. INTERVENTIONS: Unilateral vestibular implantation with an investigational multichannel vestibular implant in a 55-year-old man with a well-documented 23-year history of aminoglycoside-induced BVH. MAIN OUTCOME MEASURES: Electrically evoked vestibulo-ocular reflexes (eeVOR). RESULTS: Vestibular implant stimulation can drive stimulus-aligned eeVOR and elicit a vestibular percept 23 years after the onset of bilateral vestibulopathy. Prosthetic stimulation targeting individual semicircular canals elicited eye movements that approximately aligned with each targeted canal's axis. The magnitude of the eeVOR response increased with increasing stimulus current amplitude. Response alignment and magnitude were similar to those observed for implant recipients who underwent vestibular implantation less than 10 years after BVH onset. Responses were approximately stable for 18 months of continuous device use (24 h/d except during sleep). CONCLUSIONS: Vestibular implantation and prosthetic electrical stimulation of semicircular canal afferent nerves can drive canal-specific eye movement responses more than 20 years after the onset of ototoxic vestibular hypofunction.