Auditory Recovery Research Articles

Bursts of vagus nerve stimulation paired with auditory rehabilitation fail to improve speech sound perception in rats with hearing loss

Hearing loss can lead to long-lasting effects on the central nervous system, and current therapies, such as auditory training and rehabilitation, show mixed success in improving perception and speech comprehension. Vagus nerve stimulation (VNS) is an adjunctive therapy that can be paired with rehabilitation to facilitate behavioral recovery after neural injury. However, VNS for auditory recovery has not been tested after severe hearing loss or significant damage to peripheral receptors. This study investigated the utility of pairing VNS with passive or active auditory rehabilitation in a rat model of noise-induced hearing loss. Although auditory rehabilitation helped rats improve their frequency discrimination, learn novel speech discrimination tasks, and achieve speech-in-noise performance similar to normal hearing controls, VNS did not enhance recovery of speech sound perception. These results highlight the limitations of VNS as an adjunctive therapy for hearing loss rehabilitation and suggest that optimal benefits from neuromodulation may require restored peripheral signaling.

Exploring Audiologic Outcomes in Sudden Sensorineural Hearing Loss: A Retrospective Analysis.

Objective This retrospective study aims to present the audiologic outcomes of patients aged 18 years and above who underwent treatment for sudden sensorineural hearing loss (SSNHL) at the tertiary Hospital Central Sur Petróleos Mexicanos in Mexico City, Mexico, between January 2000 and December 2015. Main outcome measures The main outcome measures were patient demographics (age, sex, comorbidities) time from symptom onset to diagnosis and treatment initiation, initial threshold, treatment details (type, dosage, duration), adverse effects, audiometry at diagnosis and at the end of treatment, follow-up duration, and pure-tone average. Results A total of 72 patients were included, with a mean follow-up duration of four months. Comorbidities such as type 2 diabetes mellitus, hypertension, and hypertriglyceridemia were observed in a significant portion of patients. However, these conditions and the use of salvage therapy and adjuvant drugs did not impact hearing recovery. A longer delay from symptom onset to medical attention was associated with a lower gain in decibels (p=0.307). Diabetic patients who received steroid treatment showed a significant gain of at least 15 dB, indicating the greatest benefit in this subgroup. Conclusions Adjuvant drugs may be unnecessary and ineffective in treating SSNHL. Metabolic disorders may be linked to the development of SSNHL. Steroid treatment is the only effective therapeutic option for improving hearing recovery in diabetic patients. Early initiation of treatment after symptom onset is crucial for maximizing auditory recovery.

Electroacupuncture Promotes Neuroplasticity of Central Auditory Pathway: An Auditory Evoked Potentials Study.

Our previous studies found that electroacupuncture at the right Zhongzhu acupoint (TE3) can enhance auditory recovery in rats with noise-induced hearing loss. Here, we investigated the changes in auditory brainstem response (ABR) and long late latency (LLR) evoked potential to explain the mechanisms of electroacupuncture at TE3. The auditory evoked potentials were recorded, including ABR and LLR, at baseline and on day 3 (D3), D5, and D8 after baseline. The 2-Hz electroacupuncture at the right TE3 was applied on D3, D4, and D5 in the electroacupuncture group but not in the control group. In ABR, compared with the control group, the latency shift of waves I (0.298 ± 0.033 vs -0.045 ± 0.057 ms), III (0.718 ± 0.038 vs -0.163 ± 0.130 ms), and V (1.160 ± 0.082 vs -0.207 ± 0.138 ms) on D3 (all p < 0.01) and of wave V (0.616 ± 0.433 vs -0.352 ± 0.209 ms, p < 0.05) on D5 was greater in the electroacupuncture group than that in the control group. Moreover, the interpeak latency shift of I-III (0.420 ± 0.041 vs -0.118 ± 0.177 ms) and I-V (0.863 ± 0.088 vs -0.162 ± 0.156 ms) on D3 (both p < 0.05) and of III-V (0.342 ± 0.193 vs -0.190 ± 0.110 ms) and I-V (0.540 ± 0.352 vs -0.343 ± 0.184 ms) on D5 (both p < 0.05) was greater in the electroacupuncture group than that in the control group. In LLR, the latency shift of P0 was greater in the electroacupuncture group than in the control group on D3 (3.956 ± 2.975 vs -1.178 ± 1.358 ms, p < 0.01) and D5 (2.200 ± 1.889 vs -0.311 ± 1.078 ms, p < 0.05). These findings indicate that electroacupuncture at the right TE3 can modulate the neuroplasticity of the central auditory pathway, including the brain stem and the primary and secondary auditory cortex.

Hearing outcomes and patient satisfaction after stapes surgery: local versus general anaesthesia.

Otosclerosis is a frequent ear disorder causing a stapedo-ovalar ankylosis and conductive hearing loss. Stapedoplasty, performed under both general (GA) and local anaesthesia (LA), is the most advisable surgical solution. Auditory recovery relies on the patient's conditions and on the intervention itself. The aim of our work was to compare hearing outcomes with stapedoplasty performed under GA or LA and to investigate patients' compliance to both methods. Fifty-five otosclerotic patients underwent stapedoplasty both under GA (32/55) and LA (23/55). Pre- and post-operative air and bone tone audiometry threshold values as well as the air-bone gap and its closure score, were analysed. All patients filled in a satisfaction questionnaire regarding their concern and level of appreciation of the type of anaesthesia. Our data show that the auditory results with stapedoplasty are good and do not differ between LA and GA. Even considering the advantages and limits of the two methods, one cannot favour one or the other type of anaesthesia. Finally, the patient's satisfaction cannot be considered a criterion of choice, since this was found to be high in both cases.

Diagnostic value and prognostic significance of MRI findings in sudden sensorineural hearing loss.

PurposeWe evaluated the clinical significance of magnetic resonance imaging (MRI) findings and their prognostic value for initial hearing loss and recovery in patients with sudden sensorineural hearing loss (SSNHL).Materials and MethodsThis retrospective study included consecutive adult patients with unilateral SSNHL, contrast‐enhanced MRI and audiometric testing evaluated in our institution between 2005 and 2017. MRI reports, patient data, treatment, and audiometric tests were reviewed, with the relationship between MRI findings and hearing loss/recovery analyzed.ResultsOverall, 266 patients were included. Additional symptoms comprised tinnitus (114/266; 43%), vertigo (45/266; 17%), ear pain (26/266; 10%), and ear pressure (6/266; 2%). At least one cardiovascular risk factor (hypertension, diabetes, hypercholesterolemia, cardiopathy, and active smoking) existed in 167/266 (63%) patients. Corticosteroid treatment was followed by 198/266 (74%) patients while contraindications/refusal/compliance precluded treatment in 68/266(26%). Complete, partial or slight hearing recovery occurred in 167/266 (63%) patients. Three MRI patient groups were identified: a group with normal MRI examinations or incidentalomas (128/266; 48%), a group with peripheral auditory system (PAS) lesions (95/266; 36%), and a group with central nervous system (CNS) lesions (43/266; 16%). PAS lesions included lesions from the cochlea to the brain stem (e.g., schwannoma, meningioma, labyrinthitis, intracochlear hemorrhage, vestibulocochlear neuritis), whereas CNS lesions corresponded in 42/43(98%) of cases to leukoaraiosis and other vascular lesions (e.g., stroke, hemorrhage, aneurysm, venous sinus thrombosis, and cavernoma). Belonging to one of the three MRI groups did not influence the degree of initial hearing loss, affected frequencies or treatment, p > .05. Gender and cardiovascular risk factors did neither affect initial hearing loss nor recovery. However, age > 70 years negatively affected initial hearing loss in all frequencies, as well as recovery in all frequencies except 1000 Hz. Also, poor recovery of initial high‐frequency hearing loss (>1000 Hz) was significantly associated with CNS lesions.ConclusionAge > 70 years and CNS lesions depicted by MRI independently predicted poor auditory recovery, albeit in different frequencies.Lay SummaryIn patients with sudden hearing loss, older age (above 70 years) predicts poorer hearing recovery than in younger patients in most hearing frequencies. In addition, abnormalities of brain tissue revealed by MRI predict poorer hearing recovery at high frequencies.Level of EvidenceLevel III.

Acoustic neuromas associated with sudden sensorineural hearing loss

Background Several studies have reported sudden sensorineural hearing loss (SHL) as an initial symptom of acoustic neuromas (ANs). Aims/Objectives We aimed to retrospectively evaluate the incidence of SHL and the associated rates of post-treatment improvement in patients diagnosed with ANs. Materials and Methods We analysed the clinical data of 686 patients with ANs and examined tumour size, correlation with hearing loss, number of episodes of SHL, extent of auditory recovery, and associated audiogram patterns. Results Among 686 enrolled patients with ANs, 232 (86 with intracanalicular and 146 with extrameatal tumours) experienced SHL at some point in their clinical history. The incidence of SHL was not significantly associated with tumour size. Of the 172 patients analysed, 119, 44, and 9 patients experienced one, two, or three or more episodes of SHL, respectively. Confirmed auditory recovery occurred in 61%, 45.3%, and 33.3% of the patients after the first, second, or third or later episodes of SHL, respectively. The audiograms of 78/172 (45.3%) patients showed a typical trough-shaped pattern of hearing loss at medium-level frequencies. Conclusions and Significance Among patients with ANs, 7.7% experienced two or more episodes of SHL. The recovery rate of SHL decreased with each successive occurrence.

Neural recovery function of the auditory nerve in cochlear implant surgery: Comparison between different regions of the cochlea

Introduction Cochlear implants allow measures of neural function, through Neural response telemetry (NRT) and Auditory nerve recovery function (REC). These help in programming the speech processor and understanding the auditory system. However, not many studies have evaluated and compared these in different regions of the cochlea. Objective Comparing NRT and REC in different regions of the cochlea. Methods Cross-sectional, descriptive and prospective. NRT and REC (through the function of T0 – absolute refractory period, A – amplitude and TAU – time constant of the relative refractory period parameters) were evaluated, in three groups according to the stimulated electrode of the cochlea: apical, medial and basal. Results 26 adult patients were evaluated, 2 bilateral, totalling 28 ears. Data analysis showed no statistically significant difference between NRT between medial and basal but showed between apical and medial and apical and basal. For T0, there was a significant difference between medial and basal; for A, there was a significant difference between apical and basal and also medial and basal; and for TAU, there was no significant difference. Conclusion There was a statistically significant difference in NRT and REC when compared between different regions of the cochlea.

Intralabyrinthine Hemorrhage After General Anesthesia: Case Report

Several cases of intralabyrinthine hemorrhage are described in the literature. The causes are mainly anticoagulants and blood disorders. The diagnosis is suspected on clinical examination (sudden cochleo-vestibular syndrome) and confirmed by inner ear magnetic resonance imaging (MRI). We report the case of a 58-year-old woman with a history of neuro-syphilis with motor sequelae, ischemic heart disease under antiplatelet therapy, rheumatoid arthritis and colonic adenocarcinoma treated by surgery and adjuvant chemotherapy. This patient presented a unilateral cochleovestibular syndrome immediately after a short general anesthesia. MRI showed a spontaneous T1 signal hyperintensity confirming a left labyrinthine hemorrhage. The clinical course was marked by regression of balance disorders without auditory recovery. Intralabyrinthine hemorrhages are rare and often secondary to anticoagulants or blood diseases. Through this article, we report a case of intralabyrinthine hemorrhage secondary to a brief general anesthesia.

Chapter 7 - Cross-modal integration and plasticity in the superior temporal cortex

In congenitally deaf people, temporal regions typically believed to be primarily auditory enhance their response to nonauditory information. The neural mechanisms and functional principles underlying this phenomenon, as well as its impact on auditory recovery after sensory restoration, yet remain debated. In this chapter, we demonstrate that the cross-modal recruitment of temporal regions by visual inputs in congenitally deaf people follows organizational principles known to be present in the hearing brain. We propose that the functional and structural mechanisms allowing optimal convergence of multisensory information in the temporal cortex of hearing people also provide the neural scaffolding for feeding visual or tactile information into the deafened temporal areas. Innate in their nature, such anatomo-functional links between the auditory and other sensory systems would represent the common substrate of both early multisensory integration and expression of selective cross-modal plasticity in the superior temporal cortex.

Initial outcomes of the cochlear implant surgery at 108 Military Central Hospital

Objective: To assess the initial outcomes of cochlear implant (CI) surgery and the auditory recovery of the patients underwent CI surgery at the Ear-Nose-Throat Department, 108 Military Central Hospital from January 2016 to June 2020. Subject and method: Twenty-two CI recipients were included in this study. Result: 50% of the included subjects was younger than six years old, had prelingual and severe to profound hearing loss bilaterally. No severe complications was observed except the two cases with minor ones. Postoperatively, 80 - 90% of the subjects was able to recognize and discriminate the environmental sounds and the six ling sounds. Postoperative free field tests gained to normal or mild hearing loss. Conclusion: CI surgery is an effective approach for managing cases with severe to profound hearing loss.

Effect of Electroacupuncture on Noise-Induced Hearing Loss in Rats.

Acupuncture has long been used to relieve some inner ear diseases such as deafness and tinnitus. The present study examined the effect of electroacupuncture (EA) on noise-induced hearing loss (NIHL) in animals. A NIHL rat model was established. Electroacupuncture pretreatment at 2 Hz or posttreatment at the right Zhongzhu (TE3) acupoint was applied for 1 hour. Auditory thresholds were measured using auditory brainstem responses (ABRs), and histopathology of the cochlea was examined. The results indicated that the baseline auditory threshold of ABR was not significantly different between the control (no noise), EA-only (only EA without noise), noise (noise exposure only), pre-EA (pretreating EA then noise), and post-EA (noise exposure then posttreating with EA) groups. Significant auditory threshold shifts were found in the noise, pre-EA, and post-EA groups in the immediate period after noise exposure, whereas auditory recovery was better in the pre-EA and post-EA groups than that in the noise group at the three days, one week (W1), two weeks (W2), three weeks (W3), and four weeks(W4) after noise stimulation. Histopathological examination revealed greater loss of the density of spiral ganglion neurons in the noise group than in the control group at W1 and W2. Although significant loss of spiral ganglion loss happened in pre-EA and post-EA groups, such loss was less than the loss of the noise group, especially W1. These results indicate that either pretreatment or posttreatment with EA may facilitate auditory recovery after NIHL. The detailed mechanism through which EA alleviates NIHL requires further study.

Morpho-Syntactic Deficit in Children with Cochlear Implant: Consequence of Hearing Loss or Concomitant Impairment to the Language System?

Background: Among implanted children with similar duration of auditory deprivation and clinical history, the morpho-syntactic skills remain highly variable, suggesting that other fundamental factors may determine the linguistic outcomes of these children, beyond their auditory recovery. The present study analyzed the morpho-syntactic discrepancies among three children with cochlear implant (CI), with the aim of understanding if morpho-syntactic deficits may be characterized as a domain-specific language disorder. Method: The three children (mean age = 7.2; SD = 0.4) received their CI at 2.7, 3.7, and 5.9 years of age. Their morpho-syntactic skills were evaluated in both comprehension and production and compared with 15 age-matched normal-hearing children (mean age = 6.6; SD = 0.3). Results: Cases 1 and 2 displayed a marked impairment across morphology and syntax, whereas Case 3, the late-implanted child, showed a morpho-syntactic profile well within the normal boundaries. A qualitative analysis showed, in Cases 1 and 2, language deficits similar to those of normal hearing children with Developmental Language Disorder (DLD). Conclusions: We suggest that a severe grammatical deficit may be, in some implanted children, the final outcome of a concomitant impairment to the language system. Clinical implications for assessment and intervention are discussed.

Hearing recovery after surgical resection of non-vestibular schwannoma cerebellopontine angle tumors.

Post-operative outcomes for hearing after resection surgery to remove cerebellopontine angle (CPA) tumors other than vestibular schwannomas (VS) are not well understood. This study presents a series of patients with significant post-operative hearing recovery, trying to define the incidence among all patients operated on for removal of non-VS CPA tumors. This is a retrospective observational case series of 8 patients among 69 operated on for removal of non-VS CPA tumors between 2012 and 2020. All patients had pre- and post-operative hearing measurement with pure-tone average (PTA) and speech discrimination score (SDS), according to the American Academy of Otolaryngology-Head and Neck Surgery recommendations, auditory brainstem response (ABR) measurements and imaging. Six meningiomas and two lower cranial nerve schwannomas operated on with a retrosigmoid approach were included for analysis. The mean pre-operative PTA and SDS were 58 ± 20.7dB and 13 ± 17.5%, respectively. All patients had pre-operative class D hearing and asynchronous ABRs. They all showed significant hearing recovery, with an improvement of 36 ± 22.2dB (p = 0.0025) and 85 ± 16.9% (p = 0.0001) in PTA and SDS, respectively, with mean follow-up of 21 ± 23.5months. Seven patients recovered to a class A hearing level and one patient to class B. The ABRs became synchronous for three patients. The incidence of auditory recovery was 13% for patients operated on with a conservative approach (n = 60). A significant post-operative improvement in hearing could be a reasonable expectation in non-VS tumors extending into the CPA and a retrosigmoid approach should always be considered regardless of pre-operative hearing status.

Conventional approaches versus laser CO2 surgery in stapes surgery: a multicentre retrospective study.

To analyze and compare surgical and audiological outcomes of conventional approaches versus laser CO2 surgery in stapes surgery. 333 patients who underwent stapes surgery were enrolled in the study; the patient population was divided into three groups: group 1: 170 patients treated with conventional stapedotomy with manual microdrill (average age 49.13years); group 2: 119 patients treated with conventional stapedotomy with electrical microdrill (average age 51.06years); group 3: 44 patients (average age 50.4years) who underwent CO2 laser stapedotomy. Intra-operative, postoperative outcomes and audiological results were investigated. The average surgical time of laser CO2 surgery was longer than for other surgical procedures. No statistical differences emerged in post-operative abnormal taste sensation. There was also no difference in postoperative dizziness. Air-bone gap (ABG) went down from 29.7 ± 10dB (group 1) and 27.32 ± 9.20 (group 2) to 10 ± 6.9dB (group 1) and 10.7 ± 6.03dB (group 2). In group 3 the preoperative ABG was lowered from 28.3 ± 10.1 to 11.8 ± 10.9, with a statistical difference in auditory recovery (p = 0.0001); The group of patients treated with laser CO2 showed a percentage of patients with an ABG closure of between 0 and 10dB higher than in the group treated with manual microdrills (77.2% vs. 60%, respectively; p = 0.03). Overall surgical results of CO2 laser and conventional stapedotomy are comparable without any significant difference; however, the group treated with CO2 laser appears to have a percentage of patients with an ABG closure 0-10dB higher than the group treated using the conventional technique.

Sudden sensorineural hearing loss (SSHL) diagnostic delay during COVID-19 pandemic: a single-center retrospective study

BaCKgrOUND: the COViD-19 pandemic caused a diagnostic delay in various conditions, including sudden sensorineural hearing loss (SShl). the aim of this study was to investigate whether during the COViD-19 emergency period patients with a diagnosis of SShl received a late diagnosis and if any delay resulted in a worse post-therapy outcome. MEthODS: a retrospective study was conducted. Patients who received a diagnosis of SShl during COViD-19 period and in the same period of the previous year were identified (control group);demographic and clinical data, values of the tonal threshold at the time of diagnosis (T0) and after therapy (t1) and the recovery rate were collected. rESUltS: Sixteen patients of group 1 (control group) and 11 of group 2 (COViD-19 period) met the inclusion criteria. Diagnosis and therapy were performed on average after 1.69 days in group 1, after 5.45 days from the onset of symptoms in group 2 (P=0.0025). after therapy, the audiometric control examination showed an average threshold recovery of 26.77 dB in group 1 and 20.53 dB in group 2 (P=0.048). in group 1, 62.5% experienced recovery of the hearing threshold while in group 2 only 36.4% (P=0.252). CONClUSiONS: Despite therapy starting time was inevitably different in analyzed groups, diagnostic delay during COViD-19 emergency period resulted in a reduced improvement in the mean tonal threshold after therapy. Our data seems to confirm the hypothesis that early diagnosis and treatment are associated with a higher probability of auditory recovery. © 2020 EDiZiONi MiNErVa MEDiCa

Ocular and cervical vestibular-evoked myogenic potentials in idiopathic sudden sensorineural hearing loss (ISSHL) without vertigo: VEMPs in ISSHL.

Idiopathic sudden sensorineural hearing loss (ISSHL) is a hearing impairment greater than 30dB at three consecutive frequencies developing in less than 3days. The aim of this study was to evaluate VEMPs and caloric testing in patients affected by ISSHL without vertigo. We retrospectively evaluated 35 subjects affected by ISSHL. The audio-vestibular investigation consisted of pure-tone and speech audiometry, impedance, bithermal caloric testing, oVEMPs and cVEMPs. VEMPS were abnormal in 21 patients (60%): cVEMPs in 12 (34.2%) and oVEMPs in 19 (54.2%). 10 patients (28.5%) presented with both c-and oVEMPs altered. Subjects without vestibular involvement showed a significant lower PTA in the affected ear both at admission and at discharge. Recovery rate was significantly higher in group without vestibular involvement. The evaluation of the vestibular system can be useful for predicting the auditory recovery in patients without vertigo also.

Spatial Cues Influence Time Estimations in Deaf Individuals.

SummaryRecent studies have reported a strong interaction between spatial and temporal representation when visual experience is missing: blind people use temporal representation of events to represent spatial metrics. Given the superiority of audition on time perception, we hypothesized that when audition is not available complex temporal representations could be impaired, and spatial representation of events could be used to build temporal metrics. To test this hypothesis, deaf and hearing subjects were tested with a visual temporal task where conflicting and not conflicting spatiotemporal information was delivered. As predicted, we observed a strong deficit of deaf participants when only temporal cues were useful and space was uninformative with respect to time. However, the deficit disappeared when coherent spatiotemporal cues were presented and increased for conflicting spatiotemporal stimuli. These results highlight that spatial cues influence time estimations in deaf participants, suggesting that deaf individuals use spatial information to infer temporal environmental coordinates.

Sound Level Measurements in Berthing Areas of an Aircraft Carrier

Personnel assigned to aircraft carriers work and live in environments where hazardous noise areas and hearing recovery spaces such as sleeping areas are in close proximity to one another. Hazardous noise exposure occurring during on-duty time periods and elevated noise levels during off-duty periods in sleeping areas may be prohibiting adequate hearing recovery, thus potentially leading to hearing loss and may lead to adverse effects on sleep, leading to crew-member fatigue. This investigation characterizes Equivalent sound level (Leq) and standardized octave band center frequency noise levels according to berthing (sleeping) area location during flight operation and nonflight operation time periods on a US Navy aircraft carrier. In addition, the investigation compares noise measurements in sleeping areas to noise levels associated with auditory rest and poor sleep quality and quantity. Noise levels were measured in berthing areas aboard a US Navy Nimitz-class aircraft carrier during a routine at-sea period. Sixty noise measurements were taken in eight sleeping locations. Leq in decibels 'A' weighted (dBA) and noise levels from 16 to 16 000 Hz in (dB) were measured during flight operations [Leq (flt ops)] and nonflight operations [Leq (nonflt ops)]. Leq was also measured according to sleep area shipboard locations of forward (FWD) Leq (FWD), middle (MID) Leq (MID), and rear (AFT) Leq (AFT). These data were compared to the 70 dBA American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit value (TLV) for effective quiet areas. In addition, these data were compared to noise levels associated with hearing loss and sleep parameters. Statistical analysis was conducted with R version 3.5.2 using an alpha level of 0.05. Leq (flt ops) in sleeping areas was a statistically significant (P < 0.05) 6.4 dBA higher than the Leq (nonflt ops). Leq (FWD) and Leq (MID) in sleeping areas was a statistically significant (P < 0.05) 15.2 and 15.0 dBA higher, respectively, than the Leq (AFT) noise levels. Mean noise levels at standardized center (1/1) octave bands were highest between 500 and 4000 Hz, ranging from 65.2 to 69.8 dB. A total of 72% of all area Leq measurements exceeded the 70 dBA ACGIH TLV classified as effective quiet to allow for temporary threshold shift recovery. All noise measurements exceeded the World Health Organization's noise threshold where adverse effects on sleep begin. Results suggest that sleeping area location in close proximity to relatively high noise sources and activities occurring on an aircraft carrier (i.e. flight operations) increase noise levels in sleeping areas. These findings raise serious concerns since high noise exposures both on duty and during off-duty/sleeping periods may inhibit auditory recovery from hazardous noise exposures. In addition, results suggest noise levels in sleeping areas are high enough to evoke negative sleep effects.

Prediction of hearing recovery in sudden deafness treated with intratympanic steroids.

SUMMARYThe present study aims to obtain a probability model allowing prediction of auditory recovery in patients affected by sudden sensorineural hearing loss treated exclusively with intratympanic steroids. A monocentric retrospective chart review of 381 patients has been performed. A Probit model was used to investigate the correlation between the success of treatment (marked or total recovery according to Furuashi’s criteria) and the delay between onset of disease and beginning of therapy. The age of patients and audiometric curve shapes were included in the analysis. The results show that delay is negatively correlated with variable success. Considering the entire sample, each day of delay decreases the probability of success by 3%. The prediction model shows that for each day that passes from the onset of the disease the probability of success declines in absence of the medical treatment, hence we conclude that early treatment is strongly recommended.

Categorisation of natural sounds at different stages of auditory recovery in cochlear implant adult deaf patients

Previous studies have demonstrated that cochlear implant (CI) patients are more efficient at performing sound categorisation than sound identification. However, it remains unclear how this categorisation capacity develops with time during the rehabilitation period after implantation. To investigate the role of the post-implantation auditory experience in the broad sound categorisation in CI patients, we recruited CI patients with different durations of CI experience: Newly implanted CI patients (less than six months), Intermediate CI patients (6–14 months) and Experienced CI patients with a duration of implantation greater than 14 months. The patients completed a Free Sorting Task (FST), which allowed them to categorise 16 natural sounds based on their own criteria. We found an early deficit in categorisation, especially for vocal sounds; the categorisation started to improve after approximately six months post-implantation with a change of categorisation strategy which relied on different acoustic cues as a function of time after CI. The separation of the category of vocal sounds from other sounds significantly increased between the Newly implanted and Intermediate groups, i.e. as experience with the cochlear implant was acquired. The categorisation accuracy of vocal sounds was significantly correlated with the post-implantation period only in the group of newly implanted CI patients. This is the first study to show that the categorisation of vocal sounds with respect to non-vocal sounds improves during the rehabilitation period post-implantation. The first six-month post-implantation period appears to be crucial in this process. Our results demonstrate that patients in different rehabilitation periods use different acoustic cues, which increase their complexity with the CI experience.