These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Neurophysiological and histopathological evaluation of low-dose radiation on the cauda equina and postlaminotomy fibrosis: an experimental study in the rat.
    Author: Su WR, Lee JS, Chen HH, Wang LC, Huang YH, Jung YC, Jou IM.
    Journal: Spine (Phila Pa 1976); 2009 Mar 01; 34(5):463-9. PubMed ID: 19247166.
    Abstract:
    STUDY DESIGN: We evaluated the electrophysiological changes to the cauda equina after low-dose external irradiation in a postlaminotomy fibrosis model in rats. OBJECTIVE: To clarify the immediate and long-term electrophysiological responses of antifibrotic radiation therapy in a fibrosis model. SUMMARY OF BACKGROUND DATA: Low-dose perioperative radiation therapy inhibits scar formation. However, its efficacy for preventing fibrosis-induced compressive neuropathy and its potential adverse effect on underlying neural structures have not been studied. METHODS: Twenty-four rats were placed in 3 groups of 8: group I, sham operation (laminar exposure alone) with a single fraction of 700 cGy external irradiation given using a 9-MeV electron beam 24 hours postsurgery; group II, left L5 hemilaminectomy (laminotomy) alone; and group III, left L5 hemilaminectomy with the same radiation protocol as group 1. We recorded mixed-nerve-elicited somatosensory-evoked potentials (M-SSEP)- and dermal (D)-SSEP at the thoracolumbar junction, and L1-L2 interspinous ligament after percutaneously stimulating the posterior tibial nerve at the bilateral medial ankle and L5 dermatomal fields. We compared the potentials recorded immediately before, 30 minutes, 2 weeks, and 1, 2, and 3 months after surgery on the operated and nonoperated sides. We used gross dissection and histologic sections to evaluate the degree of perineural fibrosis and walking-track analysis for neurologic evaluation. RESULTS: Pre- and postoperative (30 minutes and 2 weeks) M- and D-SSEP were not statistically different. In group II, the relative amplitude of D-SSEP (elicited from 5 dermatomes) 1, 2, and 3 months postsurgery was lower; however, the M-SSEP in all groups and D-SSEP of groups I and III remained constant. Histologic evaluation of radiation efficacy showed that the frequency and extent of peridural fibrosis was consistently lower in group II than in group III. CONCLUSION: Low-dose irradiation reduced peridural fibrosis and prevented fibrosis-induced radiculopathy. The radiation caused no adverse neuropathic complications.
    [Abstract] [Full Text] [Related] [New Search]