Prussak's space: chronological development and routes of aeration.

Investigation of Prussak's space and its relationship to adjacent spaces is important in elucidating the cause of retraction pocket and cholesteatoma formation in this space. This study was designed to quantitatively characterize the chronological development of Prussak's space and its relationship to adjacent spaces in temporal bones. One-hundred and forty-nine human temporal bone slides (115 normal, 28 with otitis media with effusion, three with retraction pockets and three with attic type cholesteatoma) including specimens ranging from fetal to adult bones were studied. Prussak's space was formed and sufficient aeration routes established by 4 years of age in normal temporal bones. In temporal bones with otitis media with effusion, however, the growth of Prussak's space was suppressed and few routes for aeration established until 10 years of age. In normal temporal bones, Prussak's space developed with aeration routes sufficient to avert the negative pressure which can result in retraction pocket formation in the pars flaccida of the tympanic membrane.