Francesca Atturo

The Pre- and Post-Somatic Segments of the Human Type I Spiral Ganglion Neurons - Structural and Functional Considerations Related to Cochlear Implantation

Highlights • Pre- and post-somatic segments of type I spiral ganglion neurons (SGNs) are unmyelinated in man.• Following hair cell loss and retrograde nerve degeneration SGNs survive as “mono-polar” cells in human deafness.• Non-myelinated Schwann cells may consolidate the neural cell bodies and protect SGNs from further degeneration.• Human SGNs can persist as electrically excitable mono-polar cells even after long-time deafness.• Robust survival of human SGNs is a prerequisite for cochlear implant function.

3-D gel culture and time-lapse video microscopy of the human vestibular nerve

Abstract Conclusions: Human inner ear neurons have an innate regenerative capacity and can be cultured in vitro in a 3-D gel. The culture technique is valuable for experimental investigations of human inner ear neuron signaling and regeneration. Objectives: To establish a new in vitro model to study human inner ear nerve signaling and regeneration. Methods: Human superior vestibular ganglion (SVG) was harvested during translabyrinthine surgery for removal of vestibular schwannoma. After dissection tissue explants were embedded and cultured in a laminin-based 3-D matrix (Matrigel™). 3-D growth cone (GC) expansion was analyzed using time-lapse video microscopy (TLVM). Neural marker expression was appraised using immunocytochemistry with fluorescence and laser confocal microscopy. Results: Tissue explants from adult human SVG could be cultured in 3-D in a gel, indicating an innate potential for regeneration. Cultured GCs were found to expand dynamically in the gel. Growth cone expansion and axonal Schwann cell alignment were documented using TLVM. Neurons were identified morphologically and through immunohistochemical staining.

Esteem® middle ear device versus conventional hearing aids for rehabilitation of bilateral sensorineural hearing loss

This retrospective study aimed to evaluate the efficacy of the Esteem® middle ear implant in sensorineural hearing loss (SNHL) of different degree as well as to compare it with that obtained with conventional hearing aids. Fifteen out of 30 adults patients who received an Esteem® middle ear device for rehabilitation of sensorineural hearing loss met the primary eligibility criterion of prior, continuous use of conventional hearing aids. Study population included moderate-to-severe SNHL (8 patients) and severe-to-profound SNHL (7 patients). Audiometric measurements included free-field pure-tone and speech audiometry in Esteem®-aided, HA-aided, and baseline threshold. For speech audiometry, speech reception threshold (SRT) and word recognition score (WRS) were assessed. Subjective benefit was evaluated by Client Oriented Scale of Improvement (COSI) questionnaire. In all the subjects, SRT and WRS showed improvement both with conventional HA and Esteem® in respect to the unaided situation. Although not statistically significant, a slight prevalence of the Esteem® performances was recorded both audiometrically and as subjective satisfaction score. The Esteem® middle ear device demonstrated appreciable benefit for rehabilitation of SNHL of different degree, comparable to what can be achieved by conventional hearing aids. In addition, this rehabilitative process may enable also individuals presenting with severe-to-profound SNHL to achieve remarkable functional outcomes.

Is the Bone-Conduction HeadBand test useful for predicting the functional outcome of a round window active middle ear implant?

Objective To estimate the reliability of the Bone Conduction-HeadBand (BC-HB) test for predicting the postoperative functional outcome of a round-window (RW) vibroplasty. Study Design Within-subject comparison of the functional results of the BC-HB test, which is routinely used for the preoperative evaluation of a bone-conduction transducer, with an active middle ear implant (AMEI) placed onto the round window. Setting Tertiary referral university hospital center. Patients Seven patients with similar anatomic (absent stapes superstructure) and functional (moderate, mixed hearing loss) sequelae from open tympanoplasty technique. Intervention All subjects underwent preoperative audiologic assessment with the BC-HB. Subsequently, all subjects underwent surgical placement of an AMEI onto the round window. Main Outcome Measure Pure tone and speech audiometry in quiet and noise were assessed. Additionally, evaluation of specific satisfactory targets was performed using the Client Oriented Scale of Improvement. Results Pure tone and speech audiometry in quiet established that both devices had very similar performance and provided remarkable improvement compared with the unaided condition. However, high-frequency gain and speech audiometry in noise demonstrated better performance with RW-AMEI. Conclusion In patients presenting with mixed hearing loss as a sequela from middle ear surgery, the preoperative BC-HB test may be helpful in predicting the final functional outcome and patient satisfaction with RW-AMEI.

Hearing loss in autoimmune disorders: Prevalence and therapeutic options

The objective of this study was to review our current knowledge relative to the correlation between sensorineural hearing loss (SNHL) and autoimmune diseases, focusing on the prevalence of hearing loss in different pathologies and possible therapeutic approaches. A review of the literature on hearing loss in different forms of autoimmune disease has been carried out, with emphasis on incidence and prevalence of SNHL. Therapeutic protocols have been assessed including both conservative medical and rehabilitative methods. Cochlear implant outcomes have been investigated. The prevalence of hearing loss in autoimmune and immune-mediated inner ear diseases, as referred by case reports or single-center statistics, is widely variable. More difficult is the evaluation of severe/profound SNHL, usually reported in relation to cochlear implantation. Though these patients represent ideal candidates for cochlear implantation, as they become deaf after years of hearing; the associated systemic disease, the specific damage on inner ear structures and the medication taken may influence the result of cochlear implantation. The main problem is the cochlear fibrosis or ossification that has been found to affect 50% of implanted ears in patients suffering from autoimmune and immune-mediated SNHL. Hence, in the presence of severe/profound SNHL earlier implantation may be indicated before post-inflammatory obliterative changes to the cochlea.

Can unilateral, progressive or sudden hearing loss be immune-mediated in origin?

Abstract Objective: The aim of the present study was to demonstrate that the positivity of nonspecific immunological tests could be found not only in bilateral hearing loss but also in unilateral cases, either sudden or progressive. Method: An observational case series study included subjects suffering from unilateral or bilateral, sudden or progressive, symmetric or asymmetric sensorineural hearing loss (SNHL). All the patients underwent pure tone audiometry and the following battery of blood exams: anti-nuclear antibody (ANA), extractable nuclear antigen (ENA) antibody screening, anti-thyroperoxidase (anti-TPO), anti-thyroglobulin and anti-smooth muscle antibody (ASMA). Results: The positivity to nonspecific immunological test was found in nearly 70% of the study groups. ASMA and ANA were found to be present in both bilateral and unilateral cases, without statistical difference. Considering the correlation between positivity/negativity and systemic autoimmune pathologies, in the bilateral forms of hearing loss, a high incidence of thyroid pathologies has been identified, with a higher percentage of systemic autoimmune diseases in respect to the normal population. Conclusions: The nonspecific autoimmune tests are worth to be performed also when SNHL is not bilateral and progressive, since an immunological mechanism could also underlie unilateral and sudden SNHL cases.

Patient satisfaction after auditory implant surgery: ten-year experience from a single implanting unit center

Abstract Conclusions: The satisfaction rate of the subjects with an auditory implant appears strictly related to the resulting auditory improvement, and the surgical variables would play a prevailing role in respect to the esthetic factors. Objectives: To assess the rate of satisfaction in subjects who underwent the surgical application of an auditory device at a single Implanting Center Unit. Method: A series of validated questionnaires has been administered to subjects who underwent the surgical application of different auditory devices. The Glasgow Benefit Inventory (GBI), the Visual Analog Scale (VAS), and the Abbreviated Profile of Hearing Aid Benefit (APHAB) have been used to compare the implanted situation with the hearing-aided one; a percutaneous bone conductive implant (pBCI) with an active middle ear implant (AMEI) on the round window in mixed hearing loss; and an invisible, fully-implantable device with a frankly and bulky semi-implantable device. Results: The mean GBI scores were higher in Vibrant Soundbridge (VSB)® and Bonebridge® subjects, without significant differences among the various devices. The mean VAS score increased for all the devices in comparison with the conventional hearing aid. The mean APHAB score was similarly better in the implanted condition as total and partial scores.

Bone conductive implants in single-sided deafness

Abstract Conclusion: Bone conduction implants (BCIs) have been shown to partially restore some of the functions lost when binaural hearing is missing, such as in subjects with single-sided deafness (SSD). The use of a single BCI needs to be recommended by a clinician based on thorough counselling with the SSD subject. Objectives: To perform an overview of the present capabilities of BCIs for SSD and to evaluate the reliability of the audiological evaluation for assessing speech recognition in noise and sound localization cues, which are major problems related to the loss of binaural hearing. Methods: Nine subjects with SSD who received BCI implants underwent a preoperative audiological evaluation that included sound field speech audiometry, word recognition score (WRS) testing and sound localization testing in quiet and in noise. They were also tested for the accuracy of their directional word recognition in noise and their subjective perceptions of their hearing difficulties using the APHAB questionnaire. Results: The mean maximum accuracy of word discrimination was 65.5% in the unaided condition and 78.9% in the BCI-aided condition. Sound localization in noise was better with the BCI than in the unaided condition, especially when the stimulus and noise were presented on the same side as the implanted ear. The accuracy of directional word recognition showed an improvement with the BCI with respect to the unaided condition on the BCI side, with either the stimulus in the implanted ear and the noise in the contralateral ear or with both the stimulus and noise presented to the implanted ear.

Delayed Effect of Active Pressure Treatment on Endolymphatic Hydrops

Objective: To identify eventual correlations between the effect of low-pressure treatment and endolymphatic hydrops in Ménière patients. Material and Methods: The study group consisted of subjects affected by definite Ménière disease (2015) and a severe degree of disability, who received a ventilation tube with or without a low-pressure treatment before undergoing a surgical procedure (vestibular neurectomy). After the placement of the ventilation tube, the subjects were either left alone with the tube or received 1 month of self-administered low-pressure therapy with a portable device. In all subjects, an electrocochleography (ECochG) was performed and specific questionnaires - Dizziness Handicap Inventory (DHI) and Functional Scale Level (FSL) - were completed before starting either arm of treatment, at the end of treatment, and then 3 and 6 months later. Results: All selected subjects presented with an ECochG pattern that was indicative of endolymphatic hydrops before starting either treatment. At the end of pressure treatment, 80% showed symptomatic improvement while maintaining the hydropic ECochG pattern. At the 3-month control stage, the hydropic pattern resulted normalized (<0.5) in all the improved subjects. Conclusions: Although 1 month of low-pressure treatment provided a positive symptomatological outcome, normalization of the hydropic ECochG parameters occurred only at a later time. Therefore, it is possible to assume that endolymphatic hydrops could be concurrent with a non-symptomatic stage of Ménière disease, and that the anti-hydropic effect of the low-pressure treatment, if any, would present with a certain delay after its completion.

Kabat rehabilitation for Bell’s palsy in the elderly

Abstract Conclusions: This study has confirmed the importance of combining the physical rehabilitation to the steroid treatment for a better outcome from BP in all age groups, especially in the old HB grade V. Objectives: To investigate the role played by aging in the recovery rate from peripheral facial nerve palsy. Method: In the present study, subjects affected by peripheral facial nerve palsy, distributed by age, were randomly assigned to medical treatment, either alone or associated with Kabat physical rehabilitation. Rate and speed of recovery were assessed in the younger and older groups. All the patients were also asked to fill in a specific questionnaire (beta FAce scale). A series of non-parametric tests (McNemar Chi-square and Chi-square) have been applied to verify the hypothesis of dependence of the final recovery level from the variables age and rehabilitation. Results: The results show that, when treated only by medical therapy, the HB V subjects showed no significant age difference in relation to the achievement of a HB Grade III (100% in the over 65, 80% in the under 65), whilst, in the HB IV subjects, the younger population showed a better recovery, with 89% of a good recovery (HB I or II). In the patients who received the combined protocol, a better recovery rate was found, both in HB IV and V subjects, and the younger population could reach a good recovery in 90% of HB V cases in respect to the older population (50%).