Effect of Nd?YAG laser on experimental disc degeneration part I. Biochemical and radiographical analysis

Abstract

Intervertebral disc herniation is an important health problem from both the social and economic aspect. It is often accompanied by a decrease in the content of water and proteoglycan (PG). The present study was undertaken to elucidate the effect of neodymium-yttrium-aluminum-garnet (Nd:YAG) laser on degenerated disc tissue. In this study a ventral disc herniation model in guinea pigs was performed to study the effects of ND:YAG laser on degenerated disc with low water and PG content. Effect of ND:YAG laser on degenerated cervical disc tissue is examined from the aspects of biochemistry and radiology. In the acute period water, PG, and collagen content decreased due to the ablative effect of ND:YAG laser on disc tissue. When changes in the degenerated disc in the post-laser chronic period were compared with degenerated disc findings, statistically significant changes could not be be found. From the results of this study, there is no question that the Nd:YAG laser offers many potential benefits, it remains to be proven whether or not this is of real benefit in the treatment of patients with degenerated disc disease.

Effect of Nd?YAG laser on experimental disc degeneration part II. Histological and MR imaging findings

“…Surgical procedures on the animals are described in part I of this [38]. In this research, the cervical vertebrae including C3-C4 and C4-Cs levels of animals in the first control group (Group 1, n --5) were removed en bloc for histological examination.…”

“…Germany) attached to the operating microscope was used to vaporize the degenerated discs. Laser irradiation was done in a similar manner as described previously in Acta Neurochirurgica [38]. After laser irradiation, all animals were killed at 1 (Group 3, n = 5) and 60 (Group4, n = 5 ) days, respectively.…”

“…The first part of this experimental study was related to the effect of neodymium-yttrium-aluminumgarnet (Nd:YAG) laser on degenerated disc tissue from the aspects of biochemistry and radiology [38]. Both clinical and experimental studies performed with the Nd:YAG laser, which is the most frequently used laser in endoscopic neurosurgical practice, are increasing tremendously.…”

Extensive damage to the end-plates as a complication of laser discectomy an experimental study using an animal model

“…In order to create typical protrusion of the nucleus pulposus, the anterior portion of the annulus fibrosus was weakened by a surgical incision which was permitted to heal, as described by various authors [31,46,48,49]. And, these experimental lesions are associated with the histopathological changes of disc degeneration, thus producing a similar herniation compared to human material.…”

“…After the anterior cervical region was re-explored, the animals were brought under the Nd:YAG laser source 0~ = 1,064 nm, MBB medilas Fa., Germany) to vaporize the degenerated discs. Laser irradiation was carried out in a similar manner as described in previous studies [48,49]. In brief, the laser energy was delivered to the disc between the two end-plates in the intervertebral space at 20-Wx 0.a-second pulses for 15-20 exposures, with 1.5-2.0 second pauses between pulses to prevent overheating.…”