The latest medical research on Otology Neurotology

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common monogenic form of stroke and is associated with early-onset stroke and dementia. Whether its clinical phenotype is becoming milder with better risk factor treatments and other care improvements is unknown. In a large longitudinal CADASIL cohort, we determined whether the prognosis has changed over 23 years.

Patients were identified from the Cambridge CADASIL register and the UK Familial stroke study. Change in age at stroke over the time of recruitment was determined using linear mixed-effects model, and the impact of genetic and vascular risk factors on stroke and dementia risk was further evaluated using Cox proportional hazard regression.

A total of 555 patients with CADASIL were recruited between 2001 and 2023. The age of stroke onset significantly increased over time (p<0.001), with the mean age of stroke onset for patients recruited before 2016 (n=265) at 46.7±9.2 years and 51.6±9.5 years for those recruited since 2016 (n=290). Patients recruited since 2016 had lower risks of both stroke (HR 0.36, 95% CI 0.26 to 0.50, p<0.001) and dementia (HR 0.43, 95% CI 0.19 to 0.99, p=0.046) after adjusting for sex, hypertension history, smoking status, epidermal growth factor-like repeat position and calendar effect.

The clinical phenotype of CADASIL is improving. While this may be partly explained by reduced vascular risk factors such as smoking and the identification of milder cases, differences persisted after controlling for risk factors and mutation sites. These updated risk estimates should be used when counselling patients with CADASIL on prognosis.

The totally implantable active middle ear implant Esteem® may be considered an effective alternative to conventional hearing aids (cHAs) to manage moderate-to-severe forms of sensorineural hearing loss. This study aimed to provide long-term comparative data of Esteem performances with those achieved by cHA.

From a total of 46 subjects who received unilateral application of Esteem®, and were followed up over the years, ten underwent an audiological assessment that compared the outcomes with those achieved in the contralateral ear by a cHA, considering the initially symmetric auditory thresholds in both ears. Other than pure tone audiometry and speech audiometry in quiet, the assessment was performed by using the adaptive speech in noise, i.e., Matrix test.

The mean speech intelligibility in quiet shows in the unaided situation a recognition of 50.7% at 71 dBHL, 71% at 69 dBHL with only contralateral cHA, 92% at 66 dBHL with only Esteem device and 94% at 61 dBHL with Esteem® device and contralateral cHA. The mean speech intelligibility in noise shows in the unaided situation a recognition of 36% at 71 dBHL, 56% at 69 dBHL with only contralateral cHA, 79% at 66 dBHL with only Esteem® device and 84% at 61 dBHL with Esteem® device and contralateral cHA. At Matrix test in the unaided condition, 4 patients reached 50% of intelligibility and the 50% threshold was obtained with a mean sound/noise ratio of +10 dBHL. In the contralaterally aided condition, 10 patients reached a 50% threshold in a condition of mean S/N ratio of +10.6 dBHL. In the Esteem® only and Esteem® plus cHA condition, all patients reached the 50% threshold with a mean S/N ratio of +3.4 dBHL with the Esteem® device and +0.92 dBHL with Esteem® plus a contralateral cHA, with a statistically nonsignificant difference. The mean deviation from the reference value (7.1 dB in the normal hearing population) was 17.1 dBHL, in unaided situation; this condition did not change with only the contralateral cHA (17.6 dBHL), whilst a significant improvement could be identified with only Esteem® device, where the mean deviation was 10.5 dBHL, and mostly with Esteem® device associated with the contralateral cHA, with a value of 8.02 dBHL.

The adaptive speech audiometry in noise (Matrix Test) showed that binaural stimulation provides greater benefits in the speech recognition in noise test in comparison to monaural stimulation, especially when this is carried out only by the cHA. However, the Esteem® device allowed to obtain audiological benefits that are significantly superior to those offered by cHAs, especially in cases where the hearing loss is severe and, in some cases, profound, achieving performances almost comparable to those of a cochlear implant.

We aimed to investigate electrophysiologically and histopathologically, the protective effects of intratympanic memantine, an N-methyl-D-aspartate receptor antagonist, on ototoxicity caused by cisplatin, an anti-neoplastic agent used in many types of cancer.

Thirty-seven guinea pigs with a normal auditory function were randomly allocated to group 1 (Cisplatin; n=8), group 2 (Memantine; n=8), group 3 (Cisplatin+Memantine; n=8), group 4 (Cisplatin+Physiological Serum [PS]; n=8), and group 5 (Control; n=5). Auditory assessments were conducted using distortion product otoacoustic emissions (DPOAE) within a frequency range of 1-32 kHz, and auditory brainstem responses (ABR) within 8-32 kHz. A single dose of cisplatin (12 mg/kg) was administered intraperitoneally, followed by intratympanic administration of 0.2 mL of either memantine or PS to both ears at least half an hour before cisplatin administration. Subsequent auditory evaluations were conducted 72 h after cisplatin administration. Histopathological analyses were performed using light microscopy of the right ear and scanning electron microscopy (SEM) of the left ear.

Auditory evaluations conducted before and after treatment revealed significant findings. Specifically, within groups 3 and 4, ABR thresholds were elevated at all frequencies (p=0.00), whereas the DPOAE signal-to-noise ratios were reduced at frequencies of 8, 12, 16, and 24 kHz (p=0.001, p=0.01, p=0.01, and p=0.00, respectively). Histopathologically, both light microscopy and SEM revealed that the cisplatin+memantine group exhibited fewer hair cells and nuclear degeneration in the spiral ganglion than the cisplatin and cisplatin+PS groups. Additionally, the stria vascularis thickness was greater in the cisplatin+memantine group than in cisplatin and cisplatin+PS groups.

Despite the negative electrophysiological findings, the histopathological outcomes suggest that intratympanic memantine may have a potential protective effect against cisplatin-induced ototoxicity. However, further investigations are warranted to corroborate these findings and elucidate the underlying mechanisms of action of memantine.

We were conducting this study to evaluate the effects of different hearing aid adaptation formulas on middle latency responses (MLR) in adult hearing aid users.

The study included 72 participants: those with moderate hearing loss using hearing aids with two different formulas for the last year, those with moderate hearing loss not using hearing aids, and those without hearing loss. Sixteen participants using NAL-NL1 and NAL-RP formulas were Group 1; twenty using NAL-NL2 and DSL formulas were Group 2; fifteen with hearing loss not using devices were Group 3; and twenty-one without hearing loss were Group 4. We obtained and compared MLR responses, including Na latency, Pa latency, and Na-Pa amplitude.

Group 1 mean Na-Pa amplitude value was found to be higher than Group 2 (p = 0.001). No significant difference was observed between Group 1 and Group 2 in terms of Na latency and Pa latency values (p = 0.001; p = 0.035). It was observed that the mean Na-Pa amplitude values in Group 1 and Group 2 were higher than Group 3 (p = 0.001), but this elevation reached the level of statistical significance only in Group 1. No difference was observed between Group 1, Group 2, and Group 3 in terms of Na latency and Pa latency values (p = 0.001; p = 0.035). Compared with those without hearing loss (Group 4), participants with hearing loss (Group 1, Group 2, and Group 3) had longer Na latency and Pa latency values (p = 0.001; p = 0.035), and Na-Pa amplitudes were lower (p = 0.001). The effect of current (tested) hearing aid usage time on Na latency, Pa latency, and Na-Pa amplitude values of Group 1 and Group 2 was not observed. In all groups, there was a positive correlation between audiometric airway/bone conduction pure tone averages and speech acquisition threshold values, Na latency and Pa latency values, and a negative correlation between Na-Pa amplitude values. In all groups, there was a negative correlation between speech discrimination scores and Na and Pa latency values, as well as a positive correlation between Na and Pa amplitude values. There was a positive correlation between age and Pa latency values in all groups, as well as a negative correlation between Na and Pa amplitude values.

Middle latency responses are affected by the presence of hearing loss, the use of hearing aids, and different hearing aid adaptation formulas. MLR measurements with a hearing aid can be used as an objective test to evaluate the benefit of hearing aid use.