Hearing Loss in Relation to Round Window Membrane Morphology in Experimental Chronic Otitis media

ORL ◽  
2001 ◽  
Vol 63 (6) ◽  
pp. 333-340 ◽  
Author(s):  
Leif Nordang ◽  
Matti Anniko
1975 ◽  
Vol 84 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Fumiro Suga ◽  
John R. Lindsay

Histopathology of two cases of unilateral labyrinthitis ossificans in the presence of bilateral chronic suppurative otitis media is presented. In both cases, ossification and fibrosis were limited to the scala tympani of the lower basal turn, apparently due to inflammation entering through the round window membrane. The round window was occluded by new bone and fibrous tissue presumably resulting in a conductive hearing loss in addition to the conductive loss due to middle ear lesions. Degeneration of the hair cells of the organ of Corti was limited to the lower basal turn where ossification and fibrosis occurred.


2021 ◽  
pp. 014556132199018
Author(s):  
Murat Koc ◽  
Abdullah Dalgic ◽  
Mehmet Ziya Ozuer

Objective: To investigate the effects of the mechanical trauma to the round window, a model electrode inserted into the scala tympani on the cochlear reserve, and the efficacy of topical steroids in preventing hearing loss. Materials and Methods: 21 male Wistar Albino rats were equally categorized into three groups. In all groups an initial mechanical injury to round window was created. Only subsequent dexamethasone injection was administrated into the cochlea in the subjects of group 2 while a multichannel cochlear implant guide inserted into the cochlea prior to dexamethasone administration for group 3. Distortion product otoacoustic emissions (DPOAEs) were obtained prior to and immediately after the surgical injury, eventually on postoperative seventh day (d 7). Mean signal/noise ratios (S/Ns) obtained at 2000, 3000, and 4000 Hz were calculated. Data sets were compared with non-parametric statistical tests. Results: The early intraoperative mean S/Ns were significantly less than preoperative measurements for group 1 and 2; however, preoperative and postoperative d 7 average S/Ns did not differ. There was statistically significant difference between preoperative, intraoperative and postoperative d 7 average S/Ns for group 3. Conclusion: We observed that hearing was restored approximately to the preoperative levels following early postoperative repair. However, an electrode insertion into the cochlea via round window subsequent to mechanical trauma seems to cause a progressive hearing loss. Therefore, a special care must be taken to avoid the injury to the round window membrane in the course of the placement of a cochlear implant electrode and surgery for the chronic otitis media.


2021 ◽  
pp. 014556132110091
Author(s):  
Robin Rupp ◽  
Joachim Hornung ◽  
Matthias Balk ◽  
Matti Sievert ◽  
Sarina Müller ◽  
...  

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.


1980 ◽  
Vol 89 (3_suppl) ◽  
pp. 249-253 ◽  
Author(s):  
Michael M. Paparella ◽  
Marcos V. Goycoolea ◽  
William L. Meyerhoff

Insidious inner ear complications of otitis media have been and are being studied in our laboratory. The purpose of this paper is to review these studies, coordinate, capsulize and highlight the results with emphasis on the transport role of the round window membrane.


Author(s):  
Leena Rajam K. ◽  
Vikram V. J. ◽  
Priyanka C. ◽  
Indumathi R.

<p class="abstract"><strong>Background:</strong> Chronic otitis media (COM) is a serious healthcare concern worldwide, because of the distress and economic burden to the patient and their family. Temporal bone pneumatization plays an important role in etiology, behaviour, course and outcome of COM. Pneumatisation gets poorer with growing chronicity of the disease<span lang="EN-IN">. </span></p><p class="abstract"><strong>Methods:</strong> A retrospective study was conducted between March 2015-March 2017 on female patients visiting with COM, at ENT department Kasturba Gandhi Hospital, Madras Medical College. The records were analysed of the age, duration of symptoms, associated complaints, pure tone audiogram, computerised tomography of temporal bone, mastoid surgery done according to the disease process affecting the ear<span lang="EN-IN">.  </span></p><p class="abstract"><strong>Results:</strong> 35 female COM patients were analysed, most common age group is between 31-40 years in 14 patients. There hearing loss was mild category in 27. There were 27 cases of mucosal type of chronic otitis media and 8 cases of squamous type. The CT scan with sclerosis of mastoid was the common finding<span lang="EN-IN">. </span></p><p class="abstract"><strong>Conclusions:</strong> In exclusive study on female patients with COM, the mucosal type of COM is common with mild hearing loss and sclerosed mastoid indicating the chronicity<span lang="EN-IN">.</span></p><p class="abstract"> </p>


2009 ◽  
Vol 141 (5) ◽  
pp. 584-590 ◽  
Author(s):  
Silvia Murillo-Cuesta ◽  
Fernando García-Alcántara ◽  
Elena Vacas ◽  
Jon Alexander Sistiaga ◽  
Guadalupe Camarero ◽  
...  

Objective: To assess the validity of inducing ototoxicity in rats by applying a sponge soaked in kanamycin and furosemide on the round window. Study Design: Basic, randomized, nonblind experimental study. Setting: Animal models of cochlear damage and reliable methods of local drug delivery are fundamental to study hearing loss and to design new therapies. Subjects and Methods: Four experimental groups of six Wistar rats with different methods of drug administration were used: (1) injection of subcutaneous kanamycin (400 mg/kg) and intravenous furosemide (100 mg/kg); (2) local application of a sponge soaked in saline close to the round window; (3) animals for which the sponge was soaked in a solution containing kanamycin (200 mg/mL) and furosemide (50 mg/mL); and (4) sham-operated rats. The tympanic bulla was exposed using a ventral approach, and a bullostomy was performed to visualize the round window membrane. Cochlear function was assessed by measuring the auditory brainstem response, and hearing thresholds in response to click and tone burst stimuli were determined as peak and interpeak latencies. At the end of the study, cochlear histology was analyzed. Results: Systemic administration of kanamycin and furosemide induced profound hearing loss and severe hair cell damage. Local delivery of these ototoxic drugs caused comparable damage but avoided the systemic side effects of the drug. Sham-operated and saline control animals did not experience functional alterations. Conclusion: Situating a sponge soaked in kanamycin and furosemide on the round window membrane through the ventral approach is a reliable method to provoke local ototoxicity in rats.


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