Recovery Of Hearing Loss Research Articles

Recovery of hearing loss in atypical Meniere’s disease after treatment with orofacial and neck massage: A case report

BACKGROUND A 48-year-old female presented with sudden-onset right-sided aural fullness, low-frequency hearing loss, and tinnitus. Medical history included right-sided temporomandibular joint disorder (TMJD) with crepitation, and retro-orbital headaches. The patient was diagnosed with atypical Meniere’s disease (MD) and received intratympanic steroids, prednisone, betahistine, and began a low-sodium diet; however, the patient’s symptoms worsened. CASE SUMMARY The patient sought physical therapy for TMJD; testing revealed reduced motion and dysfunction with vertical opening, lateral excursion of the mandible to the right, and tenderness to palpation. Treatment included soft tissue mobilization of right facial structures and temporal fossa, intraoral massage of the right pterygoid musculature, and massage of right neck structures. After 4 weeks, the patient noticed subjective improvement in hearing and decreased headaches. After 11 weeks, an audiogram showed that the hearing loss had recovered. The patient has continued the daily at-home intraoral/neck massage therapy and maintained normal hearing over 4 years to date. The temporal relationship between physical therapy and recovery of hearing loss suggests muscular or inflammatory etiology as at least partially causative of this patient’s symptoms. The mechanism of healing may have been due to decreased inflammation, improved blood flow, restored function of cranial nerves, or some combination of these and other unknown factors. CONCLUSION This report suggests that orofacial physical and massage therapy may be an effective treatment for the cochlear symptoms associated with MD.

Predicting Sudden Sensorineural Hearing Loss Recovery with Patient-Personalized Seigel's Criteria Using Machine Learning.

Accurate prognostic prediction is crucial for managing Idiopathic Sudden Sensorineural Hearing Loss (ISSHL). Previous studies developing ISSHL prognosis models often overlooked individual variability in hearing damage by relying on fixed frequency domains. This study aims to develop models predicting ISSHL prognosis one month after treatment, focusing on patient-specific hearing impairments. Patient-Personalized Seigel's Criteria (PPSC) were developed considering patient-specific hearing impairment related to ISSHL criteria. We performed a statistical test to assess the shift in the recovery assessment when applying PPSC. The utilized dataset of 581 patients comprised demographic information, health records, laboratory testing, onset and treatment, and hearing levels. To reduce the model's reliance on hearing level features, we used only the averages of hearing levels of the impaired frequencies. Then, model development, evaluation, and interpretation proceeded. The chi-square test (p-value: 0.106) indicated that the shift in recovery assessment is not statistically significant. The soft-voting ensemble model was most effective, achieving an Area Under the Receiver Operating Characteristic Curve (AUROC) of 0.864 (95% CI: 0.801-0.927), with model interpretation based on the SHapley Additive exPlanations value. With PPSC, providing a hearing assessment comparable to traditional Seigel's criteria, the developed models successfully predicted ISSHL recovery one month post-treatment by considering patient-specific impairments.

Characteristics of ear fullness and synaptic loss in ear fullness revealed by SV2A positron emission tomographycortical.

Studies on feeling of ear fullness (FEF) related to sudden sensorineural hearing loss(SSNHL) are limited. The mechanisms of FEF are unclear. This study aimed to explore the characteristics and related brain activation of SSNHL with FEF. A total of 269 SSNHL patients were prospectively observed and divided into two groups, with FEF and without FEF. Fifteen SSNHL patients with FEF and 20 healthy controls (HCs) were recruited and underwent 18F-SynVesT-1 static PET. Standardized uptake values ratios (SUVr) of 18F-SynVesT-1 were computed between regions of interest. The occurrence of FEF was not related to the audiogram type or severity of hearing loss. There was a positive correlation between the degree of FEF and the degree of hearing loss. Recovery from FEF was not related to the audiogram shape, the degree of hearing loss or recovery. Fifteen SSNHL patients with FEF had relatively low 18F-SynVesT-1 uptake in the right middle frontal gyrus, right inferior frontal gyrus, right middle temporal gyrus, bilateral parietal lobe sub-gyral and left medial frontal gyrus, as compared with HCs. There was no relatively high 18F-SynVesT-1 uptake in the cerebral cortex. The occurrence and recovery of FEF in SSNHL patients are not related to the classification, degree and recovery of hearing loss. The 18F-SynVesT-1 uptake in the cerebral cortex of patients experiencing SSNHL and FEF has shown alterations. This indicates that FEF may be related to cortical reorganization after the sudden impairment of unilateral auditory input.

A novel mutation in COL1A1 causing osteogenesis imperfecta/hearing loss

ObjectivesTo screen the COL1A1 and COL1A2 gene mutation sites in a family with type I osteogenesis imperfecta (OI)/hearing loss and analyze the characteristics and recovery of hearing loss in patients with osteogenesis imperfecta. MethodsThe basic clinical data of OI proband and her parents were collected, and the COL1A1 and COL1A2 genes were detected in peripheral blood by PCR amplification and generation Sanger sequencing. Literature of stapedial surgery in patients with osteogenesis imperfecta was collected. ResultsThe heterozygous mutation of the 26 exon c.1922_1923 ins C in the OI progenitor COL1A1 gene led to the amino acid frameshift mutation of p.Pro 601FS, which was not detected in the phenotypic parents. The homozygous of exon 28 c.1782>G in COL1A2 was detected in the proband and her parents, resulting in changes in the protein p.Pro 549Ala. ConclusionThe clinical symptoms of the OI proband is caused by heterozygous mutation of the 26 exon c.1922_1923 ins C in COL1A1 gene. Stapedial surgery can provide short-term and long-term hearing benefits for OI patients with hearing loss. Level of evidenceLevel 4.

Atypical Cogan’s syndrome case with recovery of hearing loss

Atypical Cogan’s syndrome case with recovery of hearing loss

Does drilling affect the hearing of contralateral normal ear after mastoid surgery?

<p><strong>Background:</strong> Chronic otitis media (COM) is a recurrent infection of the middle ear and/or mastoid air cells affecting 2-3% of global population. Mastoidectomy is the mainstay of the treatment of COM. Bone drilling during mastoidectomy procedure exposes both the ears to acoustic trauma leading to sensorineural hearing loss. The present study was conducted to assess the possible deleterious effect of drilling on hearing of contralateral normal ear by monitoring pre-operative and post-operative pure tone audibility (PTA) and otoacoustic emissions (OAE). Aims and objectives were to evaluate the effect of drill- generated noise on hearing in non-operated ear during mastoidectomy in terms of hearing loss, its nature and duration and recovery of hearing loss.</p><p><strong>Methods:</strong> An observational study was carried out in ENT department at SMS medical college and hospital, Jaipur. Total 40 patients were studied. Pre-operative and post-operative PTA and OAE were studied and compared. Mean drilling time during mastoid surgery was also studied.</p><p><strong>Results:</strong> Out of 40 subjects, maximum patients were 11-20 years of age group (37.5%) with female preponderance (57.5%). All had undergone mastiodectomy. Only 6 (15%) subjects had transient sensorineural hearing loss of contralateral normal ear as determined by comparing pre-operative and post-operative PTA and OAE. The mean recovery time was 2-3 days. The study had shown significant effect of drill generated noise on hearing of contralateral healthy ear following mastoidectomy.</p><p><strong>Conclusions</strong>: Drill-generated noise can’t be lowered to a great extent therefore drilling time should be minimized during mastoid surgeries.</p>

Characteristics and recovery of hearing loss in 573 patients with bacterial meningitis

Objective: To analyze the characteristics and prognosis of hearing loss in children with bacterial meningitis. Methods: This was a single-center retrospective cohort study. Patients diagnosed with bacterial meningitis who were hospitalized in Beijing Children's Hospital between 2010 and 2016 and older than 28 days and younger than 18 years at symptom onset were included in this study (n=573). All clinical information including hearing assessment results during hospitalization were reviewed. All patients with hearing loss were followed up to repeat their hearing test and assess their hearing condition with parents' evaluation of aural and (or) oral performance of children (PEACH). Patients were grouped according to their hearing assessment results, and Logistic regression analysis was used to analyze the risk factors for hearing loss in patients with bacterial meningitis. Results: Five hundred and seventy-three patients were enrolled in this study, including 347 males and 226 females. The onset age ranged from 29 days to 15.8 years. Two hundred and forty-six patients had identified causative pathogens, among whom 92 cases (37.4%) were pneumococcal meningitis cases. Hearing loss was found in 160 cases (27.9%) during hospitalization, involving 240 ears. Permanent hearing loss was found in 20 cases (16.9%), involving 32 ears. In the patients with permanent hearing loss, 87.5% (28/32) of ears were identified as severe or profound hearing loss during hospitalization. Logistic regression analysis showed that dystonia, the protein concentration level in cerebrospinal fluid>1 g/L, glucose concentration level lower than 1 mmol/L and subdural effusion were independent risk factors for hearing loss (OR=2.426 (1.450-4.059), 1.865 (1.186-2.932), 1.544 (1.002-2.381) and 1.904 (1.291-2.809)). Conclusions: Hearing loss is a common sequela of bacterial meningitis in children. Most patients have transient hearing loss, but patients with severe or profound hearing impairment have a higher risk of developing permanent hearing loss.

The audiovestibular manifestations as early symptoms of multiple sclerosis: a scoping review of the literature.

Multiple sclerosis (MS) is an immune-mediated, demyelinating disease of the nervous system, which may impact the audiovestibular pathway at different stages of the disease. The auditory and vestibular manifestations of MS as a presenting or early symptom are an area in which more investigation is needed. The aim of this review is to determine the auditory and vestibular symptoms, which may occur at the presenting stage of multiple sclerosis. This clinical knowledge will allow a clinician to facilitate early diagnosis and intervention of MS through appropriate onward referral. Audiological and vestibular test results, as well as magnetic resonance imagery results, will also be examined to try to determine the impact of MS on the auditory and vestibular pathways. A scoping search of the electronic databases PubMed, Scopus, Web of Science, ScienceDirect, and EBSCO was conducted in March 2020 to obtain studies specifically of patients with audiovestibular symptoms at the early or presenting stages of multiple sclerosis. Data was extracted from studies which met the inclusion criteria and studies were subsequently critically appraised and assessed for risk of bias. Eighteen papers met the inclusion criteria for this study. Results of the study found that the most common audiovestibular manifestation as a presenting symptom of MS was unilateral, moderate-profound, fluctuating, and sudden sensorineural hearing loss across all frequencies (250Hz-8000Hz). Other symptoms include tinnitus, balance abnormalities, aural pain and aural fullness, which may accompany SSHL or occur independently. The peripheral involvement of the immune-mediated mechanisms of MS was suggested by peripheral findings in vestibular examination results and the involvement of wave I ABR in patients with irreversible hearing loss. Demyelinating lesions associated with MS were suggested by results obtained from evoked potentials measurements, including ABR, VEMPs, and MLR. An understanding of the sensitivity of evoked potentials in the detection of demyelinating lesions as well as the most common audiovestibular presentations of the disease allows the practitioner to provide an appropriate onward referral for MRI which may lead to early diagnosis and intervention of MS. We suggest that there is enough evidence to include evoked potentials complementary to MRI in the detection and monitoring of MS. As the review suggests evidence of involvement of the immune-mediated mechanisms of MS on peripheral structures like the inner ear, further clinical research is recommended to explore this mechanism. Key points 1. The most common audiovestibular manifestation as an early symptom of MS was unilateral moderate to profound SSHL across all frequencies (250Hz-8000Hz). 2. Findings of the review indicated the involvement of the immune-mediated mechanisms of MS in the peripheral structures of the inner ear. 3. These findings included peripheral results in the vestibular test of the patients involved in the study and secondly, the three studies which reported an absence of full recovery of hearing loss were also three papers which within their ABR results showed abnormality of wave I 4. This is the first paper to support the theory (Di Stadio et al. 2018) [32] that immune-mediated processes of MS can spread to peripheral inner ear structures 5. The review highlighted the sensitivity of evoked potentials in detecting MS lesions in the presenting stage, particularly ABR which demonstrated that in instances in which hearing loss recovered ABR results remained abnormal.

Delineating the usage of dexamethasone-loaded cubosomes as a therapeutic armamentarium for hearing loss versus its protective effect: In-vitro and in-vivo animal study

The evidence of significant ototoxicity during the use of cisplatin as a chemotherapeutic agent has burdened its use in cancer patients. Our aim is to entrap dexamethasone (DEX) as a protective or a therapeutic agent in a sustained release formulation (cubosomes) suitable for intratympanic administration thus improving patient quality of life. DEX cubosomes were prepared using solvent evaporation and melt dispersion-emulsification methods. The study involved the physicochemical characterization of the prepared cubosomes. The optimum formula was selected for the in-vivo study where its ability to retain hearing function was tested using distortion product otoacoustic emission (DPOAE) test. DEX cubosomes showed cubic structure with homogenous particle size distribution less than 220 nm, zeta potential between −0.070 and −6.990 mV and % entrapment efficiency ranging from 74.72% to 84.11%. Sustained release behavior of cubosomes was observed where 57.8% of DEX was released in 14 days. The DPOAE test has showed that DEX cubosomes possessed a superior effect than the marketed DEX solution. The percent recovery of hearing loss for the rats receiving DEX cubosomes as a therapy or as protectant was significantly (p < 0.05) higher than those receiving DEX solution. A histopathological study showed that prepared DEX cubosomes was safe and compatible for intratympanic injection. As a conclusion, the proposed system can be efficiently utilized to attenuate the severe ototoxicity accompanied by cisplatin administration.

Sudden Sensorineural Hearing Loss in Systemic Lupus Erythematosus and Antiphospholipid Syndrome: A Clinical Review.

Sudden sensorineural hearing loss (SSNHL) is defined as a sudden loss of hearing, usually unilateral, of more than 30 dB in 3 contiguous frequencies of the tonal audiometry. SSNHL estimates an incidence ranging from 5 to 20 per 100.000 people per year. In approximately 75% of cases, a cause cannot be identified. However, it could be a clinical manifestation of Systemic lupus erythematosus (SLE) and Antiphospholipid Syndrome (APS). This review will focus on the clinical presentation, diagnosis, and management of the SLE and APS associated SSNHL. We searched in PubMed, Scopus, Lilacs, and Cochrane reviewing reports of Sudden sensorineural hearing loss in SLE and/or APS. Articles written in English and Spanish, and were available in full text, were included. In patients with SLE, bilateral involvement was frequent. Antiphospholipid antibodies were positive in the majority of the patients. Corticosteroids were the mainstay of the treatment. The auditory prognosis was poor with total hearing loss recovery reached in only 22% of patients. On the other hand, most of the patients with SSNHL and APS were males and presented associated symptoms such as vertigo, tinnitus and/or headache, 75% had bilateral disease. Lupus anticoagulant and aCL were found in equal proportions, all patients were anticoagulated, and aspirin was associated in 25% of the cases. Complete resolution or improvement of symptoms was observed in 25% of the patients. Sudden sensorineural hearing loss, can be a clinical feature of SLE and APS. Treating physicians should be aware of this devastating complication, especially when bilateral involvement occurs.

SENS-401 Effectively Reduces Severe Acoustic Trauma-Induced Hearing Loss in Male Rats With Twice Daily Administration Delayed up to 96 hours.

SENS-401 (R-azasetron besylate) is effective against severe acoustic trauma-induced hearing loss. SENS-401 has calcineurin inhibiting properties and attenuates cisplatin-induced hearing loss in a rat model. Cisplatin-induced and acoustic trauma-induced hearing loss share common apoptotic pathways. The dose-response relationship of SENS-401 (6.6 mg/kg BID, 13.2 mg/kg BID, 26.4 mg/kg QD) and treatment time-window (13.2 mg/kg BID starting 24, 72, and 96 h posttrauma) versus placebo for 28 days were evaluated in a male rat model of severe acoustic trauma-induced hearing loss (120 dB SPL, 2 h) using auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) measures followed by cochlear outer hair cell (OHC) counting with myosin-VIIa immunolabeling. All SENS-401 doses improved ABR threshold shift and recovery, reaching statistical significance (p < 0.05) for ABR threshold recoveries after 28-days treatment. DPOAE amplitude loss and recovery improved markedly for 13.2 mg/kg BID SENS-401, reaching significance after 14 days (p < 0.05). Significant improvements in ABR threshold shifts/recovery and DPOAE amplitude loss occurred with up to 96-hours delay in initiating SENS-401 (p < 0.05), and in DPOAE amplitude recovery with up to 72-hours delay (p < 0.05). Significantly more surviving OHCs were present after SENS-401 treatment compared with placebo after 24 to 96-hours delay posttrauma, with up to 5.3-fold more cells in the basal cochlea turn. In vivo data support the otoprotective potential of twice daily oral SENS-401. Improvements in hearing loss recovery make SENS-401 a promising clinical candidate for acoustic trauma-induced hearing loss, including when treatment is not initiated immediately.

Early Treatment with Growth Hormone (GH) and Rehabilitation Recovers Hearing in a Child with Cerebral Palsy

Neonatal hearing loss is one of the most common anomalies and is frequently associated with delivery problems. The effects of growth hormone (GH) on brain regeneration after an injury are well known. This paper looks at a male child diagnosed with cerebral palsy, psychomotor affectation, left spastic hemiparesis, and bilateral sensorineural hearing loss after fetal distress due to ruptured membranes before the delivery of more than 30 hours of evolution and several episodes of severe hypoglycemia. From 3.5 months of age, we treated him with GH (0.04 mg/kg/day), Melatonin (5 mg/day and 6 months later 10 mg/day) and rehabilitation, for a period of 14 months; at discharge, the child fully recovered all the disabilities produced by his cerebral palsy, including normal hearing; GMFM-88 increased from 7.84% to 48.23%; Battelle scores increased from 2 to 9 after 7 months of treatment, and to 30, 1 year after discharge. Most likely hearing loss was recovered due to the effect of GH on the production of hair cells from stem cells (only present in very young children) in the cochlear sensory epithelium. This is the first case of recovery of hearing loss in humans after GH administration. Moreover, GH administration is useful and safe for early treatment of cerebral palsy.

Early Intratympanic Methylprednisolone in Sudden SNHL: A Frequency-wise Analysis.

Sudden sensorineural hearing loss is a dire medical emergency which must be treated at the earliest to get better long term hearing results. Our study aims to determine the efficacy of intratympanic steroid (Methylprednisolone) on auditory outcomes in patients of sudden sensorineural hearing loss and study the relation between time of onset of hearing loss to start of therapy and frequency-wise recovery of hearing loss. A prospective cohort clinical study with 33 patients with sudden hearing loss of 30dB or more were treated with the intratympanic injection of methylprednisolone and the effect of the drug was observed. In this study, 33 patients with sudden onset (unilateral or bilateral) of hearing loss were treated with intratympanic methylprednisolone. The duration at which the drug was administered and the age of the participants was taken into consideration. Main outcome measures included audiometry results at low, medium and high hearing loss frequencies. The specific frequency at which the hearing improvement took place was tabulated. It was observed that hearing improved significantly if the steroid is injected within the first 4days of onset (p < 0.05) at all the frequencies. A gain of 15dB or more was achieved in more than 78% patients after injecting methylprednisolone intratympanically. A statistically significant association was found between recovery rate and frequency of hearing loss with patients showing greater improvement at low hearing loss frequency in comparison to mid and high frequencies (p < 0.05). The drug efficacy does not change with the age of the patient.

Otologic Outcomes After Blast Injury: The Brussels Bombing Experience.

After the suicide bombings in Brussels on March 22, 2016, many victims consulted our emergency department with otologic symptoms. The aim of this study was to report the otologic morbidity and outcome after acute acoustic trauma in these patients. Prospective cohort study. Tertiary referral center. Patients reporting subjective hearing loss, tinnitus, feeling of pressure in the ear, vertigo or hyperacusis after witnessing these bombings were included. All included patients were treated with systemic corticosteroid therapy, concurrent hyperbaric oxygen therapy (HBOT) was advised to each and every included patient. Participants underwent a routine otologic work-up including otoscopy, liminal audiometry, and subjective outcome measures related to tinnitus at baseline and at follow-up. Primary outcome was to describe the otologic morbidity after acute acoustic trauma (AAT). Secondary outcome was to evaluate the recovery of hearing loss, subjective symptoms, and tympanic membrane perforations. Fifty-six patients were included in our population with an average age of 27 ± 13 years, and 46% women/54% men. Thirty-two patients reported subjective hearing loss, 45 reported tinnitus, 45 reported a feeling of pressure in the ear, 2 patients experienced vertigo, and 18 patients reported hyperacusis. Otoscopic examination revealed three tympanic membrane perforation (TMP). Sensorineural hearing loss (SNHL) was observed in 41% (n = 23) and mixed hearing loss in 3.6% (n = 2). No conductive hearing loss (CHL) was observed. Follow-up was obtained in 76.8%, with the last follow-up available at 47 ± 74 days. Two perforations closed spontaneously, while one persistent perforation was successfully reconstructed with complete air-bone gap closure. There was a significant improvement in subjective symptoms. SNHL improvement was observed in 52.6% (10/19), mixed hearing loss improved in both patients. Improvement in hearing thresholds was seen in patients treated with steroids and in those treated with steroids and HBOT, there was no significant difference in the degree of improvement between these two groups. Blast-related otologic injuries have a significant impact on morbidity. Comprehensive otologic evaluation and state-of-the-art treatment may lead to a significant improvement in symptoms and hearing loss.

Blast injury to the ear: management and long term follow up at a tertiary care hospital in a terrorism affected area of North India

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; A large proportion of blast victims suffers ear injuries; however, these injuries are often overlooked.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; We assessed 411 blast victims to detect ear injury employing detailed history, otological examination, pure tone audiometry, auditory steady state response and distortion product otoacoustic emissions. TM perforations were managed by thorough cleaning of ear by suctioning, edges approximation and gelfoam splinting in group A and only suctioning in group B. Prednisolone in tapering doses was prescribed for managing hearing loss in all except those in whom it was contraindicated. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Out of 411 blast victims, 228 (55.47%) had aural trauma. All cases were males (being serving soldiers) between ages of 21 and 57 years. (Mean 37.77 years, SD 10.38). 285 ears had a perforated TM. Of these, 145 were assigned to group A while 140 were in group B. There was no significant difference in spontaneous healing of perforation between the two groups but at 5 years’ follow up group A had significantly higher number of unscarred, healthy TMs than group B (Z score=2.2111, p=0.0271). Mean pure tone average was 51.16 dB (SD 8.79 dB) at presentation and 38.91 dB (SD 7.86 dB) at 5 years. Recovery of SNHL component was significantly better in steroid treated patients.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; Edges approximation and gelfoam splinting helped in reducing scarring of TM on healing, on long follow up. Steroid treated group showed better recovery of hearing loss.&lt;/p&gt;

Optimized phospholipid-based nanoparticles for inner ear drug delivery and therapy

To develop efficient carriers for inner ear drug delivery, we prepared four kinds of phospholipid-based nanoparticles: neutral, anionic, cationic, and cationic-PEG (polyethyleneglycol) particles. PEG was used to maintain long-term particle circulation in the perilymph, avoiding non-specific binding of particles to proteins. All four nanoparticles were about 200 nm in diameter, and their zeta potentials were −4.32, −26.0, +25.8, and −0.28, respectively, for neutral, anionic, cationic, and cationic-PEG nanoparticles. To test particle efficacy in vitro, we used an artificial mucosa 100 μm in thickness to model the round window membrane (RWM) and HEI-OC1 cells, which were treated with particles containing Nile Red dye. Based on the levels of particle penetration and cellular uptake in this model system, we selected an optimal particle for further study. We also observed the movement of particles in ex vivo organotypic cultures of the organ of Corti. In mice, we analyzed the biodistribution of dexamethasone (Dex) in the inner ear after intratympanic injection of Dex-loaded nanoparticles. Then, we tested the therapeutic utility of the Dex-loaded nanoparticles in a mouse model of ototoxicity. In the auditory brainstem response (ABR) test, particle provided improved hearing loss recovery at all tested frequencies, more so than did the Dex sodium phosphate (Dex-SP) solution in current clinical use. Furthermore, quantitative PCR showed that nanoparticles reduced the levels of pro-inflammatory cytokines, exhibiting anti-inflammatory effects superior to those of Dex-SP. Thus, the surface properties of nanoparticles play pivotal roles in particle penetration and distribution after intratympanic injection. Our in vitro screening system using an artificial mucosa will also be valuable in the development of carriers for inner ear drug delivery.

Human mesenchymal stromal cell therapy for damaged cochlea repair in nod-scid mice deafened with kanamycin

BackgroundKanamycin, mainly used in the treatment of drug-resistant-tuberculosis, is known to cause irreversible hearing loss. Using the xeno-transplant model, we compared both in vitro and in vivo characteristics of human mesenchymal stromal cells (MSCs) derived from adult tissues, bone marrow (BM-MSCs) and adipose tissue (ADSCs). These tissues were selected for their availability, in vitro multipotency and regenerative potential in vivo in kanamycin-deafened nod-scid mice. MethodsMSCs were isolated from informed donors and expanded ex vivo. We evaluated their proliferation capacity in vitro using the hexosaminidase assay, the phenotypic profile using flow-cytometry of a panel of surface antigens, the osteogenic potential using alkaline phosphatase activity and the adipogenic potential using oil-red-O staining. MSCs were intravenously injected in deafened mice and cochleae, liver, spleen and kidney were sampled 7 and 30 days after transplantation. The dissected organs were analyzed using lectin histochemistry, immunohistochemistry, polymerase chain reaction (PCR) and dual color fluorescence in situ hybridization (DC-FISH). ResultsMSCs showed similar in vitro characteristics, but ADSCs appeared to be more efficient after prolonged expansion. Both cell types engrafted in the cochlea of damaged mice, inducing regeneration of the damaged sensory structures. Several hybrid cells were detected in engrafted tissues. DiscussionBM-MSCs and ADSCs showed in vitro characteristics suitable for tissue regeneration and fused with resident cells in engrafted tissues. The data suggest that paracrine effect is the prevalent mechanism inducing tissue recovery. Overall, BM-MSCs and ADSCs appear to be valuable tools in regenerative medicine for hearing loss recovery.

Does Herpes Virus Reactivation Affect Prognosis in Idiopathic Sudden Sensorineural Hearing Loss?

Objectives Several etiologies have been proposed to underlie idiopathic sudden sensorineural hearing loss (ISSNHL), including viral infection, vascular disturbance, and immune-mediated mechanisms. However, none of these mechanisms are conclusive. Should ISSNHL be caused by reactivation of a viral infection, antiviral treatment would be an important option. Thus, in this study, we reported the prognosis according to serologic test results of herpes viruses in patients with ISSNHL. We also evaluated treatment response with acyclovir and corticosteroids versus corticosteroids alone in herpes simplex virus (HSV) seropositive ISSNHL patients.Methods We compared hematologic examinations and the results of audiometry testing in 232 patients with ISSNHL. Statistical analyses for initial hearing impairment, progression of hearing impairment, recovery of hearing loss, and laboratory results were performed in all patients. All statistical analyses were performed using SPSS software.Results The 232 ISSNHL patients were divided into two subgroups according to HSV immunoglobulin M (IgM) serologic results (seropositive or seronegative). When the seropositive group was compared to the seronegative group, age, gender, body mass index (BMI), white blood cell, absolute neutrophil count, absolute monocyte count, and platelet count were not significantly different. Initial hearing level, final recovery hearing level, and recovery time were also not significantly different between the two groups (P>0.05). Though there were no significant differences in age, gender, BMI, or viral HSV IgM titer, the two groups had similar initial hearing level, final recovery hearing level, and recovery time. The difference in hearing threshold before and after treatment was larger (18.7±37.1) in the group receiving antiviral medication than in the corticosteroids group (11.0±44.5), but this difference was not significant (P=0.619).Conclusion There was no significant difference of prognosis between the patients with and without reactivation of HSV. In addition, there seems to be no benefit for the treatment of acyclovir combined with the corticosteroids in the patients with ISSNHL.

Clinical Features and Prognosis of Sudden Sensorineural Hearing Loss Secondary to Intralabyrinthine Hemorrhage.

Background and ObjectivesA number of etiologies of idiopathic sudden sensorineural hearing loss (ISSNHL) have been proposed, including viral infection, vascular disturbance, and immune-mediated mechanisms. Intralabyrinthine hemorrhage (ILH) as a cause of SSNHL is extremely rare, and there have been no studies defining the characteristics of hearing impairment and prognosis in patients with ISSNHL due to ILH. This study aimed to investigate the difference in impaired hearing patterns and prognosis for hearing recovery between patients with ISSNHL due to ILH confirmed by magnetic resonance imaging (MRI) and sex- and age-matched patients with ISSNHL due to causes other than ILH.Subjects and MethodsWe compared the results of audiometry and MRI in 12 patients who had ILH on MRI (hemorrhage group) and in 23 sex- and age-matched controls without abnormal findings related to their hearing loss on MRI (non-hemorrhage group). Initial hearing impairment, progression, and recovery of hearing loss were compared between the two groups.ResultsA majority of patients (92%) in the hemorrhage group complained of dizziness. Initial hearing impairment was more frequent in the hemorrhage group than in the non-hemorrhage group (94.09±35.9 vs. 66.66±30.1, p-value=0.036). The final recovery threshold in the hemorrhage group was worse (78.19±46.26 vs. 37.17±31.96, p-value=0.014) than that in the non-hemorrhage group. In the hemorrhage group, hearing recovery seemed to occur less often at high frequencies (2,000, 4,000, and 8,000 Hz) than at low frequencies (250, 500, and 1,000 Hz).ConclusionsThe presence of ILH was associated with poor hearing prognosis and the occurrence of vertigo. The abrupt onset of hearing loss associated with vertigo and the presence of hyperresonance on fat-suppressed T1-weighted MRI images of labyrinthic fluid strongly suggests acute intralabyrinthine hemorrhage, and is predictive of considerable hearing impairment and poor prognosis.

Long-Term Outcomes of Acute Low-Tone Hearing Loss

Background and ObjectivesAlthough acute low-tone hearing loss has been associated with cochlear hydrops or early stage Meniere's disease, its prognosis in the short-term has been reported to be better than sudden hearing loss. However, recurrence of hearing loss and possible progression to Meniere's disease remain important concerns in the clinical setting. This study aims to investigate the long-term audiological outcomes of acute low-tone hearing loss.Subjects and MethodsA retrospective review of patients presenting with a first attack of acute low-tone hearing loss was performed. Of the 77 patients, 33 were followed up for more than 3 months. Progression, recovery of hearing loss and recurrence of hearing loss were examined. Also, correlation between long-term outcomes and associated clinical factors were analyzed.ResultsTwenty-five patients (75.7%) had complete hearing recovery, five patients (15.1%) had partial recovery, two patients (6.0%) had no recovery, and one patient (3.0%) had progression of hearing loss 1 month after initial treatment. Thirty-three patients were followed up for more than 3 months (mean 22 months, range 3-79 months). Recurrences of acute low-tone hearing loss were observed in five patients (15.2%). All of the recurrences occurred during the first 12 months of follow-up. Long-term prognosis correlated with the initial therapy results (R2=0.693).ConclusionsRecurrences of hearing loss were documented in five patients (15.2%), and all of these cases occurred within one year of the first attack. Audiological outcomes after initial therapy may predict the recurrence of acute low-tone hearing loss.