Erb:YAG and Hol:YAG laser ablation of meniscus and intervertebral discs

Abstract

Erb:YAG and Hol:YAG laser ablation rates of fibrocartilage and nucleus pulposus were measured in vitro simulating clinical conditions. After ablation macroscopic and microscopic appearance of the ablation site was investigated. Hol:YAG and Erb:YAG laser mean ablation rates increased almost linearly with rising energies, showing higher total ablation rates for the Hol:YAG laser due to its higher achievable energy density. At comparable energy densities the Erb:YAG laser appears to be more effective with respect to the corresponding ablation rates. Consequently, the ablational threshold proved to be lower for the Erb:YAG laser. Whereas during Hol:YAG laser ablation, some smoke formation and considerable tissue shrinking occurred, these effects could not be observed during Erb:YAG laser ablation. Consequently macroscopic and microscopic inspection showed some thermal damage after Hol:YAG and only minimal alterations after Erb:YAG laser ablation. Adjacent thermal damage was determined and proved to be lower for the Erb:YAG laser. In our opinion the characteristics of each laser system provide certain advantages for special clinical indications.

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

“…Therefore, the increased heat produced by laser energy can cause damage to the surrounding tissue [11,15,33,53]. Recently, the introduction of new laser types has been started with the purpose of decreasing thermal damage and avoiding the prolongation of wound healing [9,20,44,45].…”

“…In neurosurgery, it is well known that the vaporarive effect of neodymium-yttrium-aluminium-garnet (Nd:YAG) laser increases in proportion to the increase in water content of the tissue [9,12]. Although much effort has been made to ascertain the possible effect of laser energy on disc tissue, the results of laser surgery on degenerated disc with low water and PG content is not yet clearly defined.…”

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

“…HNP is still one of the most challenging health problems, and posterior surgical decompression is the commonly used conventional treatment modality [12,16,33,38,43,44,47]. Recently, several percutaneous discectomy methods have been proposed as an alternative to the conventional surgical approach in the treatment of HNP [4, 11, 13-15, 21, 22, 34, 35, 40-42, 53].…”

“…The use of laser energy to ablate disc tissue was first performed by Ascher and Choy [4]. At present, several types of lasers are available for disc decompression, and the holmium:YAG laser has a theoretical advantage over the other laser systems [12,14,35,[40][41][42]47]. The Nd:YAG is the most commonly used laser for this application in spite of its unpredictable risk of thermic damage to surrounding tissue.…”

Comparative sudy of surface displacement in discs following chemonucleolysis and lasernucleotomy

“…Besides the semiinvasive methods of treatment of prolapsed discs, chemonucleolysis and percutaneous nucleotomy [1][2][3], lasernucleotomy is now established as a third method [4][5][6][7][8][9][10][11][12]. Up to now, most retrospective and prospective clinical investigations refer to chemonucleolysis as a standard procedure [1,[13][14][15][16].…”