Anesth Pain Med.  2014 Jul;9(3):209-216.

Analysis of ultrastructural changes in the rat sciatic nerve after exposure to pulsed radiofrequency using small angle X-ray scattering (SAXS)

• Lee TH
• Lee S
• Kim JH
• Jung JY
• Kim BI
• Shin TJ

Abstract

BACKGROUND
Pulsed radiofrequency (PRF) may be used in the treatment of patients with some pain syndromes that cannot be controlled by alternative techniques. The objective of the present study is to examine the ultrastructural changes in rat sciatic nerve after PRF, using synchrotron small angle X-ray scattering (SAXS).
METHODS
Twenty rats (Male Sprague-Dawley, about 250 grams) were used this study. The PRF is applied to the afferent axons of the sciatic nerves of the rats in ex vivo state, and the ultrastructure of axons were studied after 1 (N = 5), 4 (N = 5), and 6 (N = 5) weeks by SAXS. The control (N = 5) consisted of non-treated sciatic nerve to provide a statistical differential comparison.
RESULTS
In the PRF group, the periodic peaks of myelin sheath and collagen fibrils were not changed compared to the control group, in the time progression of 1, 4, and 6 weeks. But the periodic peaks of interfibrillar distance of collagen were greater at 1 and 4 weeks after PRF, comparing to the control group, but it had tendency to return to normal in 6 weeks.
CONCLUSIONS
It is suggested that PRF did not induce ultrastructural change of myelin sheath and collagen fiber, but it induced the change of distance between collagen fibrils of the nerve tissue. This change was not caused by thermal injury but by electromagnetic fields and it is reversible.

Keyword

Pulsed-RF; Sciatic nerve; Small angle X-ray scattering

MeSH Terms

Animals
Axons
Collagen
Electromagnetic Fields
Humans
Myelin Sheath
Nerve Tissue
Rats*
Rats, Sprague-Dawley
Sciatic Nerve*
Synchrotrons
Collagen