Observable by the naked eye Commonly involved sites Observable by CT Histopathology
Tympanosclerosis White sclerotic lesions Attic, fenestra vestibuli, periphery of the ossicles Ossified or calcified high-density regions in the soft tissue, ovoid, linear or web-like forms Hyaline degeneration and increased collagen formation
Perilabyrinthine ossificans Osseous tissue Tympanic antrum Osseous tissue No clear boundaries