EXTENSIVE DAMAGE TO THE END-PLATES AS A COMPLICATION OF LASER DISKECTOMY AN EXPERIMENTAL-STUDY USING AN ANIMAL-MODEL

To date, there have been no reports of experiments demonstrating the e ffects of neodymium:YAG laser (Nd:YAG laser) on the vertebral end-plat es. In this study the effect of Nd:YAG laser on end-plates was examine d in 32 guinea pigs which were randomly divided into two groups. The f irst group was the control group, the second one the Nd:YAG laser grou p. All animals had experimental disc degeneration at three levels. Re- exploration was performed two months after the surgical ventral disc h erniation. In the second group the same procedure was performed but at the end of the reexploration, Nd:YAG laser irradiation of the degener ated discs was done. The wounds in both groups were closed again. Two months later all animals were sacrificed for histological and biochemi cal analysis. The cervical spine was excised en bloc and the overlying muscles were removed. Determination of hydroxyproline was done colori metrically in the specimens harvested from each of these groups. Light microscopy was undertaken to evaluate the extent of morphological cha nges. The differences observed between the two groups were statistical ly significant (p<0.05). From the results of this study, there is the question whether the Nd:YAG laser is a useful instrument in neurosurge ry. Therefore, it remains to be proven whether or not this is of real benefit in the treatment of patients with degenerated disc disease.