Middle Ear Epithelium of Squirrel Monkey

Detailed anatomical characteristics of normal middle ear epithelium and a topographical distribution of cell types are described for the squirrel monkey. The following cell types were classified by using electron microscopy: 1) ciliated tall cell; 2) ciliated small cell; 3) non-ciliated columnar or cuboidal cell; 4) non-ciliated thin cuboidal or flat cell. Ciliated cells were found in the region of the Eustachian tube, anterior mesotympanum and hypotympanum. Columnar cells were found anterior to Jacobson's nerve and flat cells posterior to this nerve which served as a reference mark. Such findings are important in understanding normal physiology and are of special interest in interpreting pathological inflammatory alterations in man and animals ranging from mild (acute serous otitis media) to severe (chronic serous otitis media and mastoiditis).