Acute effect of anhydrous glycerol on peripheral nerve: an experimental study.

Percutaneous retrogasserian glycerol rhizotomy has shown encouraging results in the treatment of trigeminal neuralgia. An experimental study was undertaken using a rat sciatic nerve model to elucidate the mechanism of action of anhydrous glycerol and to study the acute changes which develop within one week. Extraneural glycerol was applied in 20 adult Wistar rats. Groups of five animals were sacrificed at days 1, 3, 5 and 7 respectively. The sciatic nerve of the opposite limb in the same animals was used as a control. The nerve were examined with light and electron microscopy including a morphometric study to assess the type of fibres affected. The specific pattern of involvement of larger and medium sized myelinated fibres with relative preservation of unmyelinated fibres was noted.