Thickness of the Human Round Window Membrane in Different Forms of Otitis Media

Abstract

\s=b\The thickness and morphologic characteristics of the round window membrane were evaluated in temporal bones from normal subjects as well as those with serous otitis media, purulent otitis media, and chronic otitis media. Temporal bones were studied in chronological order in six age ranges to determine the possibility of age-related differences. No significant difference in the mean thickness of the round window membrane was observed in terms of age groups in normal temporal bones or temporal bones from patients with otitis media; however, a significant difference in the mean thickness was observed in the various forms of otitis media compared with the normal round window membrane in all age groups. The membrane was thickest in patients with chronic otitis media when compared with that in normal subjects or those with serous or purulent otitis media. The epithelial layer (including the subepithelial space) and the fibrous layer were measured individually to determine in which layer the change in mean thickness occurred. These measurements showed an involvement of all layers of the round window membrane in those groups with otitis media, with maximal involvement of the combined epithelial layer and subepithelial space. (Arch Otolaryngol Head Neck Surg 1987;113:630-634) The physiologic role of the round window membrane as a phase dif¬ ferential in permitting labyrinthine fluid to move under the influence of the stapes is widely accepted.13 It is the process of diffusion through the round window membrane, however, that has attracted the attention of

Human cochlear microstructures at risk of electrode insertion trauma, elucidated in 3D with contrast-enhanced microCT

“…We found that the central thickness of the RWM varied between 0.057 mm and 0.17 mm in the four studied samples, with a distribution peak between 0.057 and 0.13 mm (Fig. 3, Supplementary Table 2), contrary to the previous measurements in the range of 0.06-0.07 mm 43,61,62 . The RWM thickness varied both between and within individuals, whereas the perimeter shape of the RWM was similar for the different anatomical sides in the same subject (IE_2L and IE_3R in Fig.…”

“…Finally, we studied the shape and the thickness of the RWM, since it is the most important surgical access point to the cochlea, and previous data were based on histological sections 61 , 62 , fixed cochleae 34 or isolated membranes 43 , all of which already lost their natural 3D form and tension by being processed or detached from the rest of the cochlea. CECT-based segmentation of fresh-frozen RWMs for the first time allowed us to analyze the thickness profile of the entire RWM in its native shape and position.…”

Change in Cochlear Response in an Animal Model of Otitis Media with Effusion

“…The membrane morphology changes due to otitis media [Sahni et al, 1987] are similar to the observations in guinea pig OME models [Cureoglu et al, 2005]. In other words, the guinea pig OME model with a much thinner round window membrane is presumably a reasonable model for the influence of middle ear pathology affecting the human round window.…”

Sensorineural Hearing Loss after Otitis Media with Effusion and Subacute Mastoiditis after Viral Infections of the Upper Respiratory Tract: A Comparative Study of Conservative and Surgical Treatment

“…1 A permeation of cytokines through the round window membrane into the inner ear spaces has been discussed as a possible cause of sensorineural hearing loss or vertigo in viral otitis media. [7][8][9][10] However, these labyrinthine side effects of viral infections do not always appear at the acute phase of infection; we observed several cases with these symptoms 3 to 4 weeks after a viral infection of the upper airways. After the classic symptoms of a viral disease such as rhinitis and coughing, patients noticed acute or progressive hearing loss, sometimes in combination with vertigo.…”

“…A study of the temporal bones of patients with serous, purulent, or chronic otitis media found a remarkable increase in the thickness of the round window membrane compared with normal temporal bone. 9 This is another sign of an inflammatory passage through the round window membrane. Some 16 years ago, we noticed patients who developed nonbacterial otitis media with effusion with a delay of 3 to 4 weeks after a viral upper respiratory tract infection or a common cold.…”