a1 Department of Otoloryngology The General Infirmary, Leeds
a2 The Department of Anatomy & Human Biology. University of Western Australia
a3 The Biochemistry Electron Microscopy Unit, University of Leeds
This is the first report of the application of a new examination technique for the assessment of cellular activity during bone resorption in chronic suppurative otitis media (CSOM). A total of nineteen incudes removed during the course of tympanomastoid surgery were studied (retraction pocket: 2; tubo-tympanic CSOM: 4; attico-antral CSOM: 13). The microscopic surface topography of each specimen was examined using the scanning electron microscopy (SEM), and the appearances are interpreted in terms of cortical cellular activity. The results suggest that the mechanism of ossicular erosion in CSOM is similar regardless of the exact type of disease. Extensively, pitted areas were seen in all specimens. These pits are morphologically indistinguishable from those characteristic of osteoclastic activity (Howship's lacunae). We conclude that in all causes the surface topography of eroded incudes is consistent with the activity of osteoclasts.
(Accepted August 16 1992)
c1 F. J. Lannigan FRCS, ENT Department, The General Infirmary, Great George Street, Leeds. LS1 3EX