Cholesteatoma: A morphologic study of stratum corneum lipids

Two different lipid-retaining fixation techniques permitted electron micros copic visualization of both intra- and extracellular lipids in cholesteatom a epithelium obtained from 25 patients. An increased number of intracellula r lipid-containing Odland bodies was demonstrated, with a maximum in the ba sal layer of the stratum granulosum, while the superior layer contained sub stantially fewer organelles than are found in normal skin. At the stratum g ranulosum/stratum corneum interface lipids secreted from Odland bodies were found in sac-like invaginations along the cell membrane but premature exoc ytosis was also frequently observed. In the intercellular spaces of the str atum corneum, multiple long sheets of lamellar structures interrupted by sl its or pores enclosed the keratinized corneocytes. The intercellular spaces seemed narrow and an extracellular barrier was not found until well above the stratum granulosum/stratum corneum interface, A similar distribution of Odland bodies and structure of intercellular lipids can occur in several d ermatoses, where the formation and maintenance of the cutaneous permeabilit y barrier are defective.