Biomaterial Database

Patterns of degeneration in the human cochlear nerve. 1995

C E Zimmermann, and B J Burgess, and J B Nadol

Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02114, USA.

The patterns of neural degeneration of the spiral ganglion were studied in 12 human pathologic specimens and 2 normal neonatal specimens. Morphometric analysis of spiral ganglion cells included the maximum cross-sectional areas of both large (type 1) and small (type II) spiral ganglion cells. The organ of Corti in segments corresponding to the spiral ganglion, was evaluated for the presence or absence of inner (IHC) and outer (OHC) hair cells and supporting cells. The relationship between degeneration of spiral ganglion cells and degeneration in the organ of Corti, the age, sex, duration of deafness, cochlear location and delay between death and fixation was evaluated statistically. Both primary and secondary degeneration of the spiral ganglion were more severe in the basal than apical half of the cochlea. Degeneration of the spiral ganglion was most severe when both IHCs and OHCs were absent in the organ of Corti. No survival advantage was identified for type II ganglion cells as has been previously reported. That is, there was no correlation between the degree of degeneration of the spiral ganglion and the prevalence of type II ganglion cells. In fact, there was more severe degeneration of type II cells when the corresponding organ of Corti was severely degenerated. These findings in the human were compared with animal models of degeneration of the spiral ganglion, and the implications for cochlear implantation were discussed.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009410	Nerve Degeneration	Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.	Neuron Degeneration,Degeneration, Nerve,Degeneration, Neuron,Degenerations, Nerve,Degenerations, Neuron,Nerve Degenerations,Neuron Degenerations
D009925	Organ of Corti	The spiral EPITHELIUM containing sensory AUDITORY HAIR CELLS and supporting cells in the cochlea. Organ of Corti, situated on the BASILAR MEMBRANE and overlaid by a gelatinous TECTORIAL MEMBRANE, converts sound-induced mechanical waves to neural impulses to the brain.	Basilar Papilla,Corti's Organ,Spiral Organ,Corti Organ,Cortis Organ,Organ, Corti's,Organ, Spiral,Organs, Spiral,Papilla, Basilar,Spiral Organs
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell
D003051	Cochlea	The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.	Cochleas
D003638	Deafness	A general term for the complete loss of the ability to hear from both ears.	Deafness Permanent,Hearing Loss Permanent,Prelingual Deafness,Deaf Mutism,Deaf-Mutism,Deafness, Acquired,Hearing Loss, Complete,Hearing Loss, Extreme,Acquired Deafness,Complete Hearing Loss,Deafness, Prelingual,Extreme Hearing Loss,Permanent, Deafness,Permanent, Hearing Loss,Permanents, Deafness
D005260	Female		Females
D006199	Hair Cells, Auditory, Inner	Auditory sensory cells of organ of Corti, usually placed in one row medially to the core of spongy bone (the modiolus). Inner hair cells are in fewer numbers than the OUTER AUDITORY HAIR CELLS, and their STEREOCILIA are approximately twice as thick as those of the outer hair cells.	Auditory Hair Cell, Inner,Auditory Hair Cells, Inner,Cochlear Inner Hair Cell,Cochlear Inner Hair Cells,Hair Cell, Auditory, Inner,Inner Auditory Hair Cell,Inner Auditory Hair Cells,Inner Hair Cells,Cell, Inner Hair,Cells, Inner Hair,Hair Cell, Inner,Hair Cells, Inner,Inner Hair Cell
D006319	Hearing Loss, Sensorineural	Hearing loss resulting from damage to the COCHLEA and the sensorineural elements which lie internally beyond the oval and round windows. These elements include the AUDITORY NERVE and its connections in the BRAINSTEM.	Deafness Neurosensory,Deafness, Neurosensory,Deafness, Sensoryneural,Neurosensory Deafness,Sensorineural Hearing Loss,Sensoryneural Deafness,Cochlear Hearing Loss,Hearing Loss, Cochlear,Deafnesses, Neurosensory,Deafnesses, Sensoryneural,Neurosensory Deafnesses,Sensoryneural Deafness,Sensoryneural Deafnesses