Audiol. Res., Volume 13, Issue 6 (December 2023) – 14 articles

Usher syndrome (USH) is an autosomal recessive disorder characterized by sensorineural hearing loss (HL), retinopathy, and vestibular areflexia, with variable severity. Although a high prevalence of behavioural and mental disorders in USH patients has been reported, few studies on these psychiatric and psychological issues have been conducted. This work describes the case of a 16-year-old boy affected by congenital bilateral sensorineural HL, presenting a suddenly altered behaviour concomitant with a decrease in visual acuity. To establish a molecular diagnosis, Whole-Exome Sequencing analysis was performed, detecting a pathogenetic homozygous variant (c. 5985C>A, p.(Tyr1995*)) within the CDH23 gene. CDH23 is a known USH type 1 causative gene, recently associated with schizophrenia-like symptoms and bipolar disorders. To date, no studies have provided evidence of a direct genotype–phenotype correlation between USH patients carrying CDH23 variants and mental/behavioural issues; however, considering the multiple biological functions of CDH23, it can be hypothesised that it could have a pleiotropic effect. Overall, this study highlights the relevance of a continuous clinical evaluation of USH patients, to monitor not only the disease progression, but to early detect any psychological or behavioural alterations, thus allowing a rapid implementation of therapeutic strategies aimed at improving their quality of life and well-being. Full article

Cochlear synaptic loss (termed cochlear synaptopathy) has been suggested to contribute to suprathreshold hearing difficulties. However, its existence and putative effects in humans remain inconclusive, largely due to the heterogeneous methods used across studies to indirectly evaluate the health of cochlear synapses. There is a need to standardize proxies of cochlear synaptopathy to appropriately compare and interpret findings across studies. Early auditory evoked potentials (AEPs), including the compound action potential (AP)/Wave I of the auditory brainstem response are a popular proxy, yet remain variable based on technical considerations. This study evaluated one such consideration—electrode array (i.e., montage)—to optimize the use of early AEP waveforms. In 35 young adults, electrocochleography (ECochG) responses were collected using vertical and horizontal montages. Standard ECochG measures and AP/Wave I and Wave II peak-to-trough amplitudes and latencies were compared between montages. Vertical montage recordings consistently produced significantly larger AP/Wave I peak-to-trough amplitudes compared to horizontal recordings. These findings support the use of a vertical electrode montage for optimal recordings of peripheral cochlear nerve activity. As cochlear synaptopathy continues to be explored in humans, the methods highlighted here should be considered in the development of a standardized assessment. Full article

Migraine pathogenic pathways may selectively target the cochlea. A qualitative and quantitative analysis of cochlear symptoms in migraine patients without vestibular migraine and/or Méniere’s disease was conducted. We examined 60 consecutive patients with history of cochlear symptoms, including fullness, tinnitus, and hearing loss. Patients were divided into two groups based on migraine history: M (migraine) and nM (no migraine). The incidence of migraine was compared to a homogeneous control group with dysfunctional and inflammatory dysphonia without cochlear symptoms. The type, time of onset, recurrence, bilaterality of symptoms, and hearing threshold were analyzed. The incidence of migraine was significantly higher (p = 0.04) in patients with cochlear symptoms than in the control group. The onset of symptoms is significantly earlier (p < 0.05) in the presence of migraine. The fullness, recurrence, and bilaterality of symptoms are associated with migraine in a statistically significant way (p < 0.05). Pure tone audiometry shows a statistically significant increase in the hearing threshold (500–1000 Hz) in group M. Based on developing findings, cochlear migraine may be considered as a novel clinical entity, like vestibular migraine. It would be the expression, in the absence of vertiginous symptoms, of a selective suffering of the anterior labyrinth by known operating mechanisms of migraine. Full article

Hearing loss stands as the most prevalent sensory deficit among humans, posing a significant global health challenge. Projections indicate that by 2050, approximately 10% of the world’s population will grapple with disabling hearing impairment. While approximately half of congenital hearing loss cases have a genetic etiology, traditional interventions such as hearing aids and cochlear implants do not completely restore normal hearing. The absence of biological treatment has prompted significant efforts in recent years, with a strong focus on gene therapy to address hereditary hearing loss. Although several studies have exhibited promising recovery from common forms of genetic deafness in mouse models, existing challenges must be overcome to make gene therapy applicable in the near future. Herein, we summarize the primary gene therapy strategies employed over past years, provide an overview of the recent achievements in preclinical studies for genetic hearing loss, and outline the current key obstacles to cochlear gene therapy. Full article

Objective: Persistent postural–perceptual dizziness (PPPD) is a syndrome described as secondary, when it is the consequence of an organic disorder (s-PPPD), or primary, when no somatic triggers can be identified. We evaluated a group of patients diagnosed as s-PPPD, with Benign Positional Paroxysmal Vertigo (BPPV) as the main somatic trigger, with the aim of identifying the predictive clinical elements of evolution towards PPPD. Study Design: Retrospective case review. Setting: Tertiary referral center. Patients: We evaluated 126 patients diagnosed with PPPD; 54 patients were classified as p-PPPD (43%) and 72 as s-PPPD (57%). Of these, 51 patients had BPPV as a somatic trigger of PPPD, and in this group, we evaluated the prevalence of some clinical features (age, sex, latency between the onset of BPPV and the final diagnosis, recurrence of BPPV and the presence of migraine headache) for comparison with a group of patients who suffered from BPPV without an evolution towards PPPD (control group). Results: In the group with PPPD secondary to BPPV, we found a significantly higher mean age and a longer latency between the onset of BPPV and the final diagnosis compared to the control group. No difference between the two groups was found regarding sex, recurrence rate and the presence of migraine headache. Conclusions: The parameters most involved as potential precipitants of PPPD after BPPV were the age of the patients and a long latency between the onset of BPPV and the final diagnosis; the mean age of the subjects who developed PPPD following BPPV was significantly higher. These findings lead us to emphasize the importance of the early identification and treatment of BPPV, especially in older patients. Full article

Background. Trauma from adverse childhood experiences (ACEs) and serious traumatic events in adulthood is a significantly prevalent concern for public-health-hearing healthcare professionals. The pediatric and geriatric populations that audiologists often work with have been shown to be at an increased risk of experiencing traumatic events. Childhood and adult trauma can significantly impact the hearing and vestibular testing and treatment of these patients. Methods. This narrative review article discusses trauma-informed care (TIC) strategies that audiologists can use to recognize and respond to trauma in patients and prevent retraumatizing patients during their encounters in audiology clinics. Conclusions. This article will provide an overview of TIC and direct the reader to resources for their continued learning. Practical guidance on implementing trauma-informed practices in clinical audiology are also provided. Full article

Both auditory and vestibular primary afferent neurons can be activated by sound and vibration. This review relates the differences between them to the different receptor/synaptic mechanisms of the two systems, as shown by indicators of peripheral function—cochlear and vestibular compound action potentials (cCAPs and vCAPs)—to click stimulation as recorded in animal studies. Sound- and vibration-sensitive type 1 receptors at the striola of the utricular macula are enveloped by the unique calyx afferent ending, which has three modes of synaptic transmission. Glutamate is the transmitter for both cochlear and vestibular primary afferents; however, blocking glutamate transmission has very little effect on vCAPs but greatly reduces cCAPs. We suggest that the ultrafast non-quantal synaptic mechanism called resistive coupling is the cause of the short latency vestibular afferent responses and related results—failure of transmitter blockade, masking, and temporal precision. This “ultrafast” non-quantal transmission is effectively electrical coupling that is dependent on the membrane potentials of the calyx and the type 1 receptor. The major clinical implication is that decreasing stimulus rise time increases vCAP response, corresponding to the increased VEMP response in human subjects. Short rise times are optimal in human clinical VEMP testing, whereas long rise times are mandatory for audiometric threshold testing. Full article

Cartilage conduction is known widely as a third hearing transmission mechanism after the air and bone conduction methods, and transducers dedicated to the production of cartilage conduction sounds have been developed by several Japanese companies. To estimate the acoustic performance of the five cartilage conduction transducers selected for this study, both airborne sounds and cartilage conduction sounds were measured. Airborne sounds can be measured using a commercial condenser microphone; however, cartilage conduction sounds are impossible to measure using a conventional head and torso simulator (HATS), because the standard-issue ear pinna simulator cannot reproduce cartilage conduction sounds with the same spectral characteristics as the corresponding sounds measured in humans. Therefore, this study replaced the standard-issue simulator with a developed pinna simulator that can produce similar spectral characteristics to those of humans. The HATS manipulated in this manner realized results demonstrating that transducers that fitted the entrance to the external auditory canal more densely could produce greater cartilage conduction sounds. Among the five transducers under test, the ring-shaped device, which was not much larger than the entrance to the canal, satisfied the spectral requirements. Full article

Acute otitis media (AOM) is one of the most common ENT diseases in children. In the antibiotic/post-antibiotic era, facial paralysis is a very rare complication of AOM (0.004–0.005%). Despite the rarity of this complication, it should be known by all physicians for proper therapeutic management to avoid serious sequelae. The aim of this review is to provide a management guide based on the current literature. Materials and Methods: Fifteen studies published between 2000 and 2022 were selected, including 120 patients (62 M/58 F) with an average age of 4.96 years old (range = 4 months–16 years; SD: 4.2). The paralysis frequently has a sudden onset and is of a severe grade (medium House–Brackmann (HB) score at onset: 4.68; SD: 0.5); however, it tends to have an almost complete recovery in most patients (88.49% HB 1 at follow-up). Results: Its first-line treatment must be based on the use of antibiotics (beta-lactam antibiotics as penicillins or cephalosporins). Corticosteroids should be used concomitantly for their anti-inflammatory and neuroprotective actions; however, there is no unanimity between authors about their application. Myringotomy, with or without ventilation tube insertion, is indicated in cases where the tympanic membrane is intact. Other kinds of surgery should be performed only in patients who have a worsening of their AOM symptoms or a worsening in HB score even with clinical treatment. Conclusions: The obtained data show that a conservative treatment can be sufficient for complete recovery in most patients, and it is preferred as the first-line therapy. Mastoidectomy should be performed only in patients with acute mastoiditis and without symptom improvement after a conservative approach. There are insufficient data in the current literature to provide clear selection criteria for patients who need to undergo mastoidectomy with facial nerve decompression. The choice of this treatment is based on an individual center expertise. Further studies are needed to clarify the role of corticosteroids and the role of facial nerve decompression in this clinical scenario. Full article

Forty-nine children who started wearing cartilage conduction hearing aids (CC-HAs) before completing elementary school (17 with bilateral hearing loss and 32 with unilateral hearing loss) were followed-up and examined. The wearing and utilization status of the CC-HA and its progress to date were evaluated. In addition, 33 participants who purchased the CC-HAs were interviewed to assess the wearing effect. Eleven of seventeen children with bilateral hearing loss and 25 of 32 children with unilateral hearing loss continued to use the CC-HAs. In terms of wearing effect, a good wearing effect was reported, even by those with unilateral hearing loss. In cases where it was difficult to wear CC-HAs stably with pasting or ear tips, it was possible to fix them stably using commercially available hair bands and eyeglass vines. In two cases, the CC-HAs were worn from infancy. With ingenuity and appropriate educational and medical support, it is possible to wear CC-HAs from infancy. Full article

This study aimed to cross-culturally translate and adapt the Consumer Ear Disease Risk Assessment (CEDRA) questionnaire into Danish for remote ear, nose, and, throat assessments in adult, first-time hearing aid users when used in conjunction with audiometric measures and visual images of the tympanic membrane. Employing field-specific guidelines, the tool underwent a rigorous translation process. This was succeeded by field testing via cognitive debriefing with 30 intendent respondents and a pilot test involving 600 adult, potential first-time hearing aid users from 2020–2022. Test–retest reliability analysis in 113 respondents revealed high consistency and reproducibility, with most items showing Spearman’s correlation coefficients of 0.82 or higher and a Pearson’s correlation of 0.92 for the total score. The tool demonstrated moderate discriminative ability in identifying individuals at high and low risk of complicated hearing loss and targeted ear diseases, supported by an area under the curve of 0.82 on the receiver operating characteristics curve. Our findings suggest that the Danish-translated version of CEDRA is a reliable and effective screening instrument when used with audiometry and tympanometry, warranting further validation in a larger population. Full article

(1) Background: Usually, the majority of patients suffering from vertigo and dizziness can be identified in four major categories: acute spontaneous vertigo, episodic (recurrent) vertigo, recurrent positional vertigo, and chronic imbalance. Our purpose is to retrospectively evaluate the main causes of episodic vertigo and to find indications for a reliable clinical suspicion useful for a definitive diagnosis, comparing patients affected by different presenting symptomatology (acute vertigo, recurrent episodic vertigo, and imbalance). (2) Methods: we retrospectively evaluated the clinical records in a population of 249 consecutive patients observed for vertigo in our tertiary referral center in the period 1 January 2019–31 January 2020. On the basis of the reported clinical history, patients were divided into three groups: patients with their first ever attack of vertigo, patients with recurrent vertigo and dizziness, and patients with chronic imbalance. (3) Results: On the basis of the results of the instrumental examination, we arbitrarily divided (for each type of symptoms) the patients in a group with a normal vestibular instrumental examination and a group of patients in which the clinical–instrumental evaluation showed some pathological results; a highly significant difference (p: 0.157) was found between recurrent and acute vertigo and between recurrent vertigo and imbalance. (4) Conclusions: Patients with recurrent vertigo more frequently exhibit a negative otoneurological examination since they are often examined in the intercritical phase. A precise and in-depth research of the patient’s clinical history is the key to suspect or make a diagnosis together with the search for some instrumental or clinical hallmark, especially in cases where the clinical picture does not fully meet the international diagnostic criteria. Full article

Low-frequency air–bone gap (ABG) associated with pulsatile tinnitus (PT) and normal impedance audiometry represents a common finding in patients with third window syndromes. Other inner disorders, including Meniere’s disease (MD), perilymphatic fistula and intralabyrinthine schwannoma, might sometimes result in a similar scenario. On the other hand, PT is frequently associated with dural arteriovenous fistula (DAVF), while conductive hearing loss (CHL) is extremely rare in this clinical setting. A 47-year-old patient was referred to our center with progressive left-sided PT alongside ipsilateral fullness and hearing loss. She also experienced headache and dizziness. Otoscopy and video-oculographic examination were unremarkable. Conversely, a detailed instrumental audio-vestibular assessment revealed low-frequency CHL with normal impedance audiometry, slight left-sided caloric weakness, slightly impaired vestibular-evoked myogenic potentials on the left and normal results on the video-head impulse test, consistent with an MD-like instrumental profile. Gadolinium-enhanced brain MRI revealed an early enhancement of the left transverse sinus, consistent with a left DAVF between the left occipital artery and the transverse sinus, which was then confirmed by angiography. A trans-arterial embolization with Onyx glue was performed, resulting in a complete recession of the symptoms. Post-operatively, the low-frequency ABG disappeared, supporting the possible role of venous intracranial hypertension and abnormal pressure of inner ear fluids in the onset of symptoms and offering new insights into the pathomechanism of inner ear CHL. Full article