The tympanic membrane is the oval-shaped window in the lateral wall of the tympanic cavity. It separates the tympanic cavity from the external acoustic meatus. This is a thin, semitransparent membrane that is attached to the tympanic sulcus by a thick ring of fibrocartilage. The handle of the malleus is attached to its medially projecting center, the umbo, on the membrane’s internal surface. The tympanic membrane has three tissue layers: an outer cuticular layer, a middle fibrous layer, and an inner mucous layer. The cuticular layer is continuous with the lining of the external acoustic meatus and is formed of stratified squamous epithelium. The fibrous layer consists of collagen fibers arranged in radial and circular patterns. The radial fibers project from the umbo outward and the circular fibers are more prominent peripherally. The mucous layer is continuous with the mucous lining of the tympanic cavity. It consists of simple cuboidal to simple squamous cells with scattered patches of ciliated cells.

Membrana tympanica

Paries membranaceus cavi tympani

Membrane du tympan