Sune Land Bloch1, Mads Sølvsten Sørensen. 1. Otopathological Laboratory, Department of Otorhinolaryngology Head and Neck Surgery, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. SuneBloch@hotmail.com
Abstract
CONCLUSION: 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.
CONCLUSION: 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.
Authors: Tamás Karosi; Péter Csomor; Anita Szalmás; József Kónya; Mihály Petkó; István Sziklai Journal: Eur Arch Otorhinolaryngol Date: 2010-10-21 Impact factor: 2.503