Cohen D
Am J Otol. 1987 Jan;8(1):61-5.
Primary cholesteatomas (PCs) are embryologic residual nests in the middle ear cleft. Based on a study of 56 cases (48 of them from the literature), a new classification is suggested: tympanic cavity PC (71% of the cases), and temporal bone PC (29%). Among the tympanic cavity cases a significant number (63%) were found in the anterosuperior quadrant. The findings support the embryologic theory for the origin of PC.
原发性胆脂瘤（PCs）是中耳裂内的胚胎残余巢。基于对56例病例（其中48例来自文献）的研究，提出了一种新的分类：鼓室PC（占病例的71%）和颞骨PC（占29%）。在鼓室病例中，相当数量（63%）位于前上象限。这些发现支持了PC起源的胚胎学理论。
