Round Window Niche and Membrane in Chronic Suppurative Otitis Media

This study evaluated the histopathologic changes in the round window niche and membrane in cases of chronic suppurative otitis media. The pathologic process was found in all subjects. Fibrocystic or fibrous tissue was most commonly seen, while active granulation was less developed. The round window membrane was thicker and inflamed throughout its layers. Inflammatory invasion of the inner ear through the membrane is very rare, because the thickened membrane has a protective role for spreading of infection