American journal of otolaryngology
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The sequela of a temporal bone fracture include hearing loss, vestibular dysfunction, and facial nerve injury. A large series of patients with temporal bone fractures are reviewed to correlate mechanism of injury, fracture location, and outcome. ⋯ Hearing loss following temporal bone fracture reflects the site and mechanism of injury. Transient conductive hearing loss may be due to blood in the middle ear, perforation of the tympanic membrane, or injury to the ossicular chain. Conductive loss persisting 6 to 7 weeks after trauma and exceeding 30 dB is an indication for surgical exploration.
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Carbonic anhydrase appears to be involved in the process of otoconial formation. The purpose of this investigation was to observe the morphologic change in the surface structure of the otolithic organ in developing chick embryos after injection of the carbonic anhydrase inhibitor, acetazolamide. Acetazolamide (1.5, 3, or 6 mg/0.06 mL/egg) was injected into the yolk sac of the embryo of the fifth day of incubation. ⋯ A widely exposed meshwork structure of otolithic membrane was observed, with sensory cilia penetrating the meshwork small holes in many instances. There were also several otoconial abnormalities, such as the appearance of only a single giant otoconium, or from several to dozens of giant otoconia, and rough, spongy-surfaced global substances entirely covering the maculae. Clearly, carbonic anhydrase inhibitor (acetazolamide) injected into the yolk sac of developing chick embryos alters and inhibits normal otoconial morphogenesis.