Hearing loss is the most common sensory deficit in the world, and most frequently it originates in the inner ear. Yet, the inner ear has been difficult to access for diagnosis because of its small size, delicate nature, complex three-dimensional anatomy, and encasement in the densest bone in the body. Evolving optical methods are promising to afford cellular diagnosis of pathologic changes in t...

This study examined the external morphology and morphometry of the human embryonic inner ear membranous labyrinth and documented its three-dimensional position in the developing embryo using phase-contrast X-ray computed tomography and magnetic resonance imaging. A total of 27 samples between Carnegie stage (CS) 17 and the postembryonic phase during trimester 1 (approximately 6-10 weeks after f...

OBJECTIVE To identify the expression of netrin-1, a diffusible chemoattractive molecule, and its receptor, deleted in colorectal carcinoma (DCC), in the developmentally mature inner ear, and to determine its effects on axon length and guidance in cultured auditory neurons. DESIGN Messenger RNA (mRNA) and protein expression of netrin-1 and DCC were identified in the organ of Corti and spiral g...

The cochlear sensory epithelium and spiral ganglion neurons (SGNs) in the adult mammalian inner ear do not regenerate following severe injury. To replace the degenerated SGNs, neural stem cell (NSC) is an attractive alternative for substitution cell therapy. In this study, adult mouse NSCs were transplanted into normal and deafened inner ears of guinea pigs. To more efficiently drive the implan...

OBJECTIVE To quantitatively demonstrate and classify the histopathologic changes in the cochlea of the human temporal bones with labyrinthitis ossificans (LO). STUDY DESIGN Comparative human temporal bone study. SETTING Tertiary academic medical center. SUBJECTS AND METHODS We compared 23 temporal bone specimens from 19 deceased donors with LO associated with the round window membrane (RW...

During gestation, the paired box-containing gene Pax2 is expressed in the mid-hindbrain area, developing eye and inner ear. We generated Pax2 null mutant mice, which show the requirement of Pax2 for the establishment of axonal pathways along the optic stalks and ventral diencephalon. In mutant brains, the optic tracts remain totally ipsilateral due to agenesis of the optic chiasma. Furthermore,...

Three-dimensional (3D) reconstruction of anatomical structures can give additional insight into the morphology and function of these structures. We compare 3D reconstructions of the guinea pig inner ear, using light microscopy and orthogonal plane fluorescence optical sectioning microscopy. Applications of 3D reconstruction of the inner ear are further explored. For each method two bullas were ...

Severe sepsis is known to result in various neurological long-term deficits in human. Recently, a link between severe, lethal sepsis and significant hearing loss with correlating histomorphological inner ear changes in mice (C57BL/6) was observed. However, if similar observations can be made in severe, non-lethal sepsis in mice is unclear. This study evaluates mice after severe, non-lethal seps...

Hair cells of the developing mammalian inner ear are progressively defined through cell fate restriction. This process culminates in the expression of the bHLH transcription factor Atoh1, which is necessary for differentiation of hair cells, but not for their specification. Loss of several genes will disrupt ear morphogenesis or arrest of neurosensory epithelia development. We previously showed...

BACKGROUND Chronic otitis media (COM) can be treated with tympanoplasty with or without mastoidectomy. In patients who have undergone middle ear surgery, three-dimensional spiral computed tomography (CT) scan plays an important role in optimizing surgical planning. OBJECTIVES This study was performed to compare the findings of three-dimensional reconstructed spiral and conventional CT scan of...