Round and Oval Window Anatomic Variability

2017 ◽  
Vol 38 (5) ◽  
pp. e50-e57 ◽  
Author(s):  
Marta Mancheño ◽  
Miguel Aristegui ◽  
Jose Ramon Sañudo
Keyword(s):  
2013 ◽  
Vol 456 ◽  
pp. 576-581 ◽  
Author(s):  
Li Fu Xu ◽  
Na Ta ◽  
Zhu Shi Rao ◽  
Jia Bin Tian

A 2-D finite element model of human cochlea is established in this paper. This model includes the structure of oval window, round window, basilar membrane and cochlear duct which is filled with fluid. The basilar membrane responses are calculated with sound input on the oval window membrane. In order to study the effects of helicotrema on basilar membrane response, three different helicotrema dimensions are set up in the FE model. A two-way fluid-structure interaction numerical method is used to compute the responses in the cochlea. The influence of the helicotrema is acquired and the frequency selectivity of the basilar membrane motion along the cochlear duct is predicted. These results agree with the experiments and indicate much better results are obtained with appropriate helicotrema size.


1988 ◽  
Vol 81 (6) ◽  
pp. 811-814
Author(s):  
Kiyotaka Murata ◽  
Michio Isono ◽  
Hiroyuki Oiki ◽  
Fumihiko Ohta ◽  
Akio Yoshida ◽  
...  

1977 ◽  
Vol 86 (4_suppl) ◽  
pp. 1-39 ◽  
Author(s):  
Gary K. Thomas

This animal experimental study (144 cats) was designed to allow observation of the healing processes at the oval window following stapedectomy during the first two postoperative weeks. The first 61 animals (Series I) had no oval window cover except for a blood clot which might form spontaneously. The second 64 animals (Series II) had Gelfoam® as a cover to the oval window following stapedectomy. A third series of 19 animals had temporalis fascia used as the oval window cover, and these ears were studied histologically for up to nine weeks. The unoperated ear acted as a control for the operated ear in all animals and after the animals were killed, both temporal bones were decalcified, imbedded in celloidin, serially sectioned at 20μ, and every tenth section stained and mounted for histologic study. It was observed that oval window closure was effected by endosteal, periosteal, and fibrous tissue proliferation from the traumatized tissues about the oval window fenestra, and that this process was facilitated by the presence of some type of scaffolding material such as a blood clot or Gelfoam®. Temporalis fascia placed in the oval window was observed to be rapidly incorporated into a much thicker oval window neomembrane and to seal the fenestra promptly. Partial removal of the footplate also facilitated more rapid closure of the smaller oval window fenestra, but fibrous tissue and new bone formation was noted to form about bony fragments still attached at the oval window level. Free bony fragments within the vestibule were not observed to stimulate new bone formation. Suppuration was observed most frequently in Series I (no oval window cover), with 67.8% of these animals having some degree of otitis media. In Series II (Gelfoam® cover) 20.6% had otitis media, and in Series III (temporalis fascia) 21% had middle ear infection. Suppuration markedly impaired but did not completely prevent the oval window reparative processes. Animals having some type of oval window cover were noted to have a lesser incidence of suppurative labyrinthine involvement when otitis media was present. Other labyrinthine complications were observed, including endolymphatic hydrops, Wittmaack's hypotonic atrophy, as well as RBC, fibrin, and albuminous precipitates in the labyrinth. Hypotonic atrophy was observed in a high incidence of animals having rupture of one or more endolymphatic structures, suggesting a mechanical mechanism as one possible explanation for this condition. Hypotonic atrophy may represent the end-stage (collapse) in the fluctuant endolymphatic ballooning of hydrops which is seen when saccular or Reissner's membrane ruptures have occurred.


2017 ◽  
Vol 19 (5) ◽  
pp. 76-80
Author(s):  
M.K. Rybakova ◽  
◽  
V.V. Mitkov ◽  
D.G. Baldin ◽  
◽  
...  
Keyword(s):  

2020 ◽  
Vol 13 (2) ◽  
pp. 106-112 ◽  
Author(s):  
Se-Joon Oh ◽  
Il-Woo Lee ◽  
Soo-Geun Wang ◽  
Soo-Keun Kong ◽  
Hong-Ki Kim ◽  
...  

Objectives. This study aimed to investigate whether optical coherence tomography (OCT) provides useful information about the microstructures of the middle and inner ear via extratympanic approach and thereby could be utilized as an alternative diagnostic technology in ear imaging.Methods. Five rats and mice were included, and the swept-source OCT system was applied to confirm the extent of visibility of the middle and inner ear and measure the length or thickness of the microstructures in the ear. The cochlea was subsequently dissected following OCT and histologically evaluated to compare with the OCT images.Results. The middle ear microstructures such as ossicles, stapedial artery and oval window through the tympanic membrane with the OCT could be confirmed in both rats and mice. It was also possible to obtain the inner ear images such as each compartment of the cochlea in the mice, but the bone covering bulla needed to be removed to visualize the inner ear structures in the rats which had thicker bulla. The bony thickness covering the cochlea could be measured, which showed no significant differences between OCT and histologic image at all turns of cochlea.Conclusion. OCT has been shown a promising technology to assess real-time middle and inner ear microstructures noninvasively with a high-resolution in the animal model. Therefore, OCT could be utilized to provide additional diagnostic information about the diseases of the middle and inner ear.


1973 ◽  
Vol 82 (1) ◽  
pp. 2-12 ◽  
Author(s):  
Victor Goodhill ◽  
Irwin Harris ◽  
Seymour J. Brockman ◽  
Oscar Hantz

In 1971, one of the authors reported sudden deafness associated with labyrinthine window membrane ruptures. Eighteen additional cases have been explored surgically since then. Data on 21 cases are presented. Sudden profound cochlear deafness has now been encountered in 21 cases which were surgically explored. In 15 instances, fistulae of round, oval, or both windows were encountered and repaired. In 10 of the 15, there was a definite history of sudden exertion or trauma prior to onset. The oval window alone was ruptured in nine patients, the round window alone in one, and both windows were ruptured in five patients. The oldest patient was 62 years and the youngest 11 years of age. Differential audiological studies showed profound losses in all cases. Almost every case was studied by pure tone AC-BC and speech audiometry, Békésy, and impedance tests. Whenever possible other audiologic tests, such as recruitment, tone decay, and SISI were performed. These findings are presented in detail. Vestibular function was studied by electronystagmography (ENG) in 15 of the 21 cases surgically explored. There was evidence of vestibular dysfunction in almost every case with sudden hearing loss. Significant ENG details are presented. Surgical repairs of ruptured window membranes were followed by improvements in some of the patients. Postoperative audiologic data are presented. The theoretical aspects include discussion of possible cerebrospinal fluid (CSF) perilymph pathways between cochlear aqueduct and scala tympani and between internal auditory meatus and scala vestibuli. It is concluded that spontaneous labyrinthine window ruptures must now be added to the etiologic factors in “sudden hearing loss.” It is premature to set down criteria for surgical intervention in such cases. Further careful studies are necessary.


2020 ◽  
Vol 26 (4) ◽  
pp. 4-12
Author(s):  
A.А. Malska ◽  
◽  
O.B. Kuryliak ◽  

Aim. To determine the rate of aortic coarctation, the correlation of its anatomical forms - critical and not critical, and the frequency of combination with the associated pathology; to define the features of the clinical course of its different anatomical forms; and to analyze the remote results of the surgical correction of this defect. Material and Methods. The article represents the statistical analysis of outpatient medical records and case histories of 86 children with aortic coarctation in Lviv region. In the course of the research, retrospective and epidemiological studies were carried out; clinical (data acquisition of medical history, physical examination), instrumental (Doppler echocardiography, ECG, X-ray imaging of organs of the thoracic cavity), and statistical methods were used. Results and Discussion. It was determined that over the period of 2008-2020 years, out of 74 neonates with CoA registered at Lviv Regional Children's Hospital (Health Care of Mother and Child) 40,54% had the critical CoA form, while 59 (46%) - uncritical CoA form. In children with the critical CoA form, the most frequent findings were hypoplasia of the aortic arch (56,67%), open aortic duct (53,33%), and open oval window (53,33%); in 36,6% cases CoA was combined with the bicuspid aortic valve, interatrial septal defect, and transposition of great vessels. However, the uncritical CoA form was more frequently combined with the bicuspid aortic valve (52,27%), and hypoplastic aortic arch (31,82%); aortic stenosis was revealed in 20,45% of children. After the surgical correction in 43,59% of the operated patients with uncritical CoA, excessive arterial hypertension was observed, while in critical form, the frequency of excessive arterial hypertension among the operated patients amounted to 10%. According to our research, after the plasty of the critical CoA, aortic recoarctation was observed in 3.33% of the operated patients, whereas, in case of the uncritical CoA form, it occurred in 30,77% of the operated ones. Conclusions. Coarctation of the aorta is a congenital heart disease with relatively high incidence, amounting to 5-8% out of all congenital defects of the heart. In newborns, it is manifested by acute cardiac failure, while in elder children it is presented with arterial hypertension. Echocardiographic examination after Doppler analysis is the basic procedure of diagnostics and allows for precise determination of the CoA anatomy. The majority of cardiologists recommend prompt surgical intervention after the diagnosis has been made, and, particularly, in patients with hypertension. At present, the available surgical methods include surgical excision of the aortic obstruction, and catheter intervention (the balloon angioplasty and stent implantation) . After the surgical correction has been performed, arterial hypertension persists. The duration of hypertension after the coarctation correction depends on its duration before the diagnosis is made and the timing of surgical correction of the defect. With the child's growth , recoarctation may occur. In such patients, normal arterial pressure can be determined in the state of rest, but it may increase in the upper extremities during physical exertion. Key words: aortic coarctation, associated pathology, excessive arterial hypertension, recoarctation


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