scholarly journals Bacterial Cytolysin Perturbs Round Window Membrane Permeability Barrier In Vivo: Possible Cause of Sensorineural Hearing Loss in Acute Otitis Media

1998 ◽  
Vol 66 (1) ◽  
pp. 343-346 ◽  
Author(s):  
Frank Engel ◽  
Rosemarie Blatz ◽  
Reinhard Schliebs ◽  
Michael Palmer ◽  
Sucharit Bhakdi
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Middle Ear ◽  
Round Window ◽  
Acute Otitis Media ◽  
Sensorineural Hearing ◽  
Round Window Membrane ◽  
Permeability Barrier ◽  
Streptolysin O

ABSTRACT The passage of radioiodinated streptolysin-O (SLO) and albumin through the round window membrane (RWM) was studied in vivo. When applied to the middle ear, SLO became quantitatively entrapped in this compartment and no passage to the cochlea occurred. However, flux of radioiodinated albumin through the toxin-damaged RWM was observed. We propose that the passage of noxious macromolecules, such as proteases, from a purulent middle-ear effusion may be facilitated by pore-forming toxins, resulting in cochlear damage and sensorineural hearing loss.

scholarly journals Cochlear Implantation Following Explorative Tympanotomy in Patients With Sudden Sensorineural Hearing Loss: Surgical Features and Audiological Outcomes

2021 ◽  
pp. 014556132110091
Author(s):  
Robin Rupp ◽  
Joachim Hornung ◽  
Matthias Balk ◽  
Matti Sievert ◽  
Sarina Müller ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Connective Tissue ◽  
Sensorineural Hearing Loss ◽  
Cochlear Implantation ◽  
Round Window ◽  
Sudden Sensorineural Hearing Loss ◽  
Sensorineural Hearing ◽  
Round Window Membrane ◽  
Hearing Results ◽  
Round Window Niche

Objective: To investigate the anatomical status of the round window niche and hearing outcome of cochlear implantation (CI) after explorative tympanotomy (ExT) with sealing of the round window membrane in patients with sudden sensorineural hearing loss at a tertiary referral medical center. Methods: Between January 1, 2007, and July 30, 2020, 1602 patients underwent CI at our department. Out of these, all patients previously treated by ExT with sealing of the round window membrane because of unilateral sudden hearing loss were included in the study. A retrospective chart review was conducted concerning method of round window membrane sealing, intraoperative findings during CI, postoperative imaging, and hearing results. Results: Twenty one patients (9 females; 8 right ears; 54.3 years [± 12.9 years]) underwent ExT with sealing of the round window membrane with subsequent CI after 26.6 months (± 32.9 mo) on average. During CI, in 76% of cases (n = 16), the round window niche was blocked by connective tissue due to the previous intervention but could be removed completely in all cases. The connective tissue itself and its removal had no detrimental effects on the round window membrane. Postoperative computed tomography scan showed no electrode dislocation. Mean postoperative word recognition score after 3 months was 57.4% (± 17.2%) and improved significantly to 73.1% (± 16.4%, P = .005) after 2 years. Conclusion: Performing CI after preceding ExT, connective tissue has to be expected blocking the round window niche. Remaining tissue can be removed safely and does not alter the round window membrane allowing for a proper electrode insertion. Short- and long-term hearing results are satisfactory. Consequently, ExT with sealing of the round window membrane in patients with sudden sensorineural hearing loss does not impede subsequent CI that can still be performed safely.

scholarly journals Design Study of a Round Window Piezoelectric Transducer for Active Middle Ear Implants

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 946
Author(s):  
Dong Ho Shin
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Middle Ear ◽  
Piezoelectric Transducer ◽  
Round Window ◽  
Piezoelectric Element ◽  
Sensorineural Hearing ◽  
Flat Band ◽  
Middle Ear Implants ◽  
Output Characteristics

This report describes the design of a new piezoelectric transducer for round window (RW)-driven middle ear implants. The transducer consists of a piezoelectric element, gold-coated copper bellows, silicone elastomer (polydimethylsiloxane, PDMS), metal cylinder (tungsten), and titanium housing. The piezoelectric element is fixed to the titanium housing and mechanical resonance is generated by the interaction of the bellows, PDMS, and tungsten cylinder. The dimensions of PDMS and the tungsten cylinder with output characteristics suitable for compensation of sensorineural hearing loss were derived by mechanical vibrational analysis (equivalent mechanical model and finite element analysis (FEA)). Based on the results of FEA, the RW piezoelectric transducer was implemented, and bench tests were performed under no-load conditions to confirm the output characteristics. The transducer generates an average displacement of 219.6 nm in the flat band (0.1–1 kHz); the resonance frequency is 2.3 kHz. To evaluate the output characteristics, the response was compared to that of an earlier transducer. When driven by the same voltage (6 Vp), the flat band displacement averaged 30 nm larger than that of the other transducer, and no anti-resonance was noted. Therefore, we expect that the new transducer can serve as an output device for hearing aids, and that it will improve speech recognition and treat high-frequency sensorineural hearing loss more effectively.

scholarly journals A Window of Opportunity: Perilymph Sampling from the Round Window Membrane Can Advance Inner Ear Diagnostics and Therapeutics

2022 ◽  
Vol 11 (2) ◽  
pp. 316
Author(s):  
Madeleine St. Peter ◽  
Athanasia Warnecke ◽  
Hinrich Staecker
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Inner Ear ◽  
Hearing Aids ◽  
Biomarker Discovery ◽  
Treatment Options ◽  
Round Window ◽  
Sensorineural Hearing ◽  
Round Window Membrane ◽  
Promising Source

In the clinical setting, the pathophysiology of sensorineural hearing loss is poorly defined and there are currently no diagnostic tests available to differentiate between subtypes. This often leaves patients with generalized treatment options such as steroids, hearing aids, or cochlear implantation. The gold standard for localizing disease is direct biopsy or imaging of the affected tissue; however, the inaccessibility and fragility of the cochlea make these techniques difficult. Thus, the establishment of an indirect biopsy, a sampling of inner fluids, is needed to advance inner ear diagnostics and allow for the development of novel therapeutics for inner ear disease. A promising source is perilymph, an inner ear liquid that bathes multiple structures critical to sound transduction. Intraoperative perilymph sampling via the round window membrane of the cochlea has been successfully used to profile the proteome, metabolome, and transcriptome of the inner ear and is a potential source of biomarker discovery. Despite its potential to provide insight into inner ear pathologies, human perilymph sampling continues to be controversial and is currently performed only in conjunction with a planned procedure where the inner ear is opened. Here, we review the safety of procedures in which the inner ear is opened, highlight studies where perilymph analysis has advanced our knowledge of inner ear diseases, and finally propose that perilymph sampling could be done as a stand-alone procedure, thereby advancing our ability to accurately classify sensorineural hearing loss.

Eosinofilik Otitis Media

2020 ◽  
Vol 5 (2) ◽  
pp. 498
Author(s):  
Putri Sari Ivanny ◽  
Effy Huriyati ◽  
Yan Edward
Keyword(s):  
Hearing Loss ◽  
Sensorineural Hearing Loss ◽  
Otitis Media ◽  
Middle Ear ◽  
Late Phase ◽  
Round Window ◽  
Sensorineural Hearing ◽  
Eosinophilic Cationic Protein ◽  
Cationic Protein ◽  
Middle Ear Mucosa

<div class="WordSection1"><p class="Body"><strong>Abstrak</strong><strong></strong></p><p><strong>Pendahuluan: </strong>Eosinofilik otitis media (EOM) merupakan otitis media yang sulit disembuhkan dengan karakteristik adanya cairan efusi berwarna kuning pada telinga tengah dengan viskositas tinggi yang mengandung akumulasi eosinofil yang luas. Onset EOM terjadi pada dekade kelima dengan perbandingan prevalensi eosinofilik otitis media pada wanita dan pria, yaitu sebesar 2 : 1. Pasien dengan EOM akan menunjukkan penurunan pendengaran yang bertahap atau cepat. <strong>Tujuan:</strong>Mengetahui dan memahami EOM.<strong>Tinjauan Pustaka:</strong>EOM dikaitkan dengan pasien yang menderita asma bronkial, polip nasal dan pasien dengan intoleransi aspirindengan ditemukannya peningkatan jumlah IgE pada mukosa telinga tengah. Pada EOM, eosinofil yang teraktivasi akan melepaskan protein sitotoksik yang disebut dengan <em>eosinophilic cationic protein </em>(ECP). Eosinofil dapat bermigrasi dan merusak telinga bagian dalam melalui <em>round window</em>. <strong>Kesimpulan: </strong>Ditemukannya eosinofil pada mukosa dan cairan efusi telinga tengah akan menyebabkan degranulasi dan dilepaskannya ECP. Produksi berlebihan dari IgE pada mukosa telinga tengah berhubungan dengan kondisi patologis dari EOM sebagai respon tipe lambat yang dimediasi IgE. Kondisi ini dapat menyebabkan kerusakan telinga bagian dalam dan berujung pada gangguan pendengaran berupa tuli sensorineural.<strong>Kata Kunci:</strong>Eosinofilik otitis media, eosinofil, IgE, ECP, tuli sensorineural</p><p class="Body"> </p><p class="Body"><strong><em>Abstract</em></strong><strong><em></em></strong></p><p class="Body"><strong><em>Introduction:</em></strong><em>Eosinophilic otitis media (EOM) is an intractable otitis media characterized by the presence of a highly viscous yellow effusion with extensive accumulation of eosinophils in the middle ear. The age at the onset of EOM is approximately in the fifties and the  female and male ratio is about 2 : 1. Eosinophilic otitis media patients show gradual or sudden deterioration of hearing.</em><strong><em>Objective: </em></strong><em>Determining and understanding the EOM. </em><strong><em> Literature Review:</em></strong><em>EOM associated with adults with bronchial asthma, nasal polyps and aspirin-intolerance by finding the elevation of IgE accumulation in the middle ear mucosa. In EOM patient, eosinophil releases cytotoxic protein called </em><em>eosinophilic cationic protein (ECP).</em><em>Eosinophil will migrate and eventually cause inner ear damage through round window. </em><strong><em>Conclusion:</em></strong><em></em><em>Most of eosinophils in the middle ear mucosa and middle ear effusion were activated, resulting in degranulation and release of ECP. Local IgE over production indicating that the intractable inflammation is closely associated with IgE-mediated late phase response. This condition will damage inner ears and can cause<strong></strong>sensorineural hearing loss.<strong> </strong></em></p><p class="Body"><strong><em>Keywords</em></strong><strong>:<em></em></strong><em>Eosinophilic otitis media, eosinophil, IgE, ECP, sensorineural hearing loss</em></p></div>

Sign in / Sign up

Export Citation Format

Share Document