The existence of hypoglossal root ganglion cells in adult humans: potential clinical implications.
BACKGROUND
Ganglion cells of the hypoglossal nerve (HN) have been confirmed in certain animals but have been thought not to be present in man. To investigate for the presence of these structures in adult humans and if present, to verify their functionality, the present study was performed.


METHODS
We harvested adult cadaveric HN and observed for ganglion cells. Histological and immunohistochemical analyses were performed on all specimens.


RESULTS
Ganglion cells were found in 33% of specimens. Using immunohistochemistry, we found that these ganglia were sympathetic in nature. Based on our findings, ganglion cells do exist in the human HN although they are located sporadically and are found inconstantly.


CONCLUSIONS
Such information may be valuable in elucidating other functions of the HN and may aid in the histological diagnosis of this nerve. Additionally, pathology involving HN such as paragangliomas, are supported by our findings of the presence of autonomic ganglion cells in some HN specimens.
Section of Pediatric Neurosurgery, University of Alabama at Birmingham, Birmingham, AL, USA. rstubbs@uab.edu
R Shane
RS
Tubbs
Diala
D
El-Zammar
Mark E
ME
Rogers
David R
DR
Kelly
Robert
R
Lott
Gina D
GD
Chua
Mohammadali M
MM
Shoja
Marios
M
Loukas
W Jerry
WJ
Oakes
Aaron A
AA
Cohen-Gadol
D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005260:Female; D005725:Ganglia, Autonomic / Q000166:cytology*; D005728:Ganglia, Sympathetic / Q000166:cytology*; D006801:Humans; D007002:Hypoglossal Nerve / Q000166:cytology*; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000166:cytology*