The spatial distribution of otosclerosis: a quantitative study using design-based stereology.
CONCLUSIONS
This study documents that otosclerotic bone remodeling is distributed centripetally around the inner ear space whereas normal bone remodeling is distributed centrifugally. We suggest that this inverse relation reflects the unique osteo-dynamic setting of the otic capsule: since perilabyrinthine bone remodeling is extremely low, osteocyte deficiency and microcracks accumulate in excess toward the inner ear space with age. This may disrupt the osseus functional network, impede propagation of anti-resorptive signals, and precipitate otosclerotic bone remodeling with a spatial preference for older bone.


OBJECTIVE
To quantify the spatial distribution of otosclerotic bone around the inner ear space in order to explore a possible spatial relation with normal capsular bone remodeling.


METHODS
Otosclerotic lesions in 53 undecalcified human temporal bones were identified and volume data were measured with the CAST-grid system and processed by dedicated software for advanced design-based stereology.


RESULTS
The maximum volume fraction of otosclerotic bone was observed in the innermost perilabyrinthine zones of the otic capsule. The volume fraction of otosclerotic bone declined gradually but significantly from the inner ear space towards the capsular periphery with a general perilabyrinthine centripetal distribution.
Bloch
Sune Land
SL
Otopathological Laboratory, Department of Otorhinolaryngology Head and Neck Surgery, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. SuneBloch@hotmail.com
Sørensen
Mads Sølvsten
MS
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016723:Bone Remodeling; D007758:Ear, Inner / Q000473:pathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D010040:Otosclerosis / Q000473:pathology*; D013701:Temporal Bone / Q000473:pathology*; D055815:Young Adult