Related Experiment Videos
Extracellular fluid pathway inside the facial nerve fascicles
Y Nakao1, T Tabuchi, N Sakihama
1Department of Otolaryngology, Nagasaki University School of Medicine, Japan.
The Annals of Otology, Rhinology, and Laryngology
|June 1, 1997
Summary
Researchers studied facial nerve fluid pathways in rabbits using a sodium fluorescein tracer. Findings indicate a diffusion pathway within the facial nerve, potentially explaining neural spread of disease to other cranial nerves.
Area of Science:
- Neuroscience
- Anatomy
- Physiology
Background:
- The facial nerve's extracellular fluid pathways are not fully understood.
- Investigating tracer diffusion from the facial nerve to adjacent cranial nerves is crucial for understanding neural pathways.
Purpose of the Study:
- To examine the extracellular fluid pathway within the facial nerve.
- To investigate the diffusion of a tracer from the facial nerve to other cranial nerves in rabbits.
Main Methods:
- Sodium fluorescein solution was injected into rabbit facial nerve fascicles or epineurial connective tissue.
- Tracer localization was performed using fluorescence microscopy at the stylomastoid foramen and geniculate ganglion.
Main Results:
- Fluorescence was observed within the facial nerve's endoneurium and external nerve sheath (epineurium and perineurium).
- Diffusion to vestibular, trigeminal, and glossopharyngeal ganglia was noted in ganglion cells and intercellular connective tissues.
Conclusions:
- The endoneurial connective tissue serves as an internal diffusion pathway within facial nerve fascicles.
- Extracellular fluid pathways from the facial nerve may facilitate neural spread of inflammation or metastasis to cranial ganglia.