Evaluation of different laser wavelengths on ablation lesion and residual thermal injury in intervertebral discs of the lumbar spine

Abstract

Laser discectomy or nucleotomy is an increasingly important method for less invasive procedures of column, but the ideal kind of laser is still not established. As the wavelength is an important parameter for water absorption, this study was performed to investigate the action of the laser emission in the near infrared (808 to 1908 nm) region in the context of surgical procedures for percutaneous intervertebral disc decompression (nucleotomy). Forty intervertebral discs from pigs lumbar spines were irradiated with laser (λ = 808, 980, 1470 and 1908 nm), 1-s on/off time cycles, for 120 cycles and 10 W of power (808, 980, and 1470 nm) or 240 cycles and 5 W of power (1908 nm), with total power of 1200 J, and subjected to microscopic evaluation through hematoxylin-eosin (HE) staining in order to measure the ablation lesions and the residual thermal injury. Ten other discs were not irradiated and worked as controls. The ablation lesions were measured (in mm) at 1.08 ± 1.25, 1.70 ± 0.63, 2.23 ± 1.02, 1.37 ± 0.39, and 0.94 ± 0.41 (median ± SD) for the control, 808, 980, 1470, and 1908 nm groups, respectively. The difference between 1908 nm and all the other groups was statistically significant (p < 0.05). The residual thermal injury was less evident in 1908 nm laser and sharper in 980 nm laser wavelengths. The laser at a wavelength of 1908 nm was considered the most efficient for the vaporization of the nucleus pulposus, followed by the laser wavelengths of 1470, 808, and 980 nm, and proved to be useful for laser nucleotomy procedure.

Comparison of A 1940 nm Thulium-Doped Fiber Laser and A 1470 nm Diode Laser for Cutting Efficacy and Hemostasis in A Pig Model of Spleen Surgery

“…In studies on the impact of different laser wavelengths on ablative and thermal damage in the intervertebral discs, a laser emitting a wavelength of 1470 nm produced a wider zone of thermal changes (2.23 ± 1.02 mm) compared with our results [12].…”

“…The wavelength of light emitted by a laser is an important parameter in terms of absorption by the water. Radiation at a wavelength of 1940 nm is effectively absorbed by water and does not penetrate deep into the tissue, which translates into higher ablation efficiency and greater precision of the procedure [12]. Although similar hemostasis in the parenchymal organs can be achieved with lower wavelengths of laser light, the degree of surrounding tissue destruction is not known [13].…”

“…For many other surgical procedures, an optimal laser has not yet been developed [12,22]. Nowadays, surgical laser devices simultaneously producing good hemostasis and limited tissue penetration are sought for minimally invasive endoscopic and robotic surgery.…”

Photobiomodulation of human adipose-derived stem cells using 810 nm and 980 nm lasers operates via different mechanisms of action

“…In medical applications, 980 nm lasers were originally developed to target the water absorption peak centered at 975 nm. High power focused 980 nm lasers have been used for tissue coagulation [26] and tissue ablation [27]. This photothermal targeting of water, combined with the relative lack of absorption peaks due to CCO at this wavelength (980 nm), does indeed suggest that the primary photoacceptor for these two wavelengths (810 nm and 980 nm) may indeed be different.…”

Avaliação da descompressão discal por via percutânea a laser em pacientes com neuralgia ciática. Utilização de comprimento de onda 980 nm com posicionamento central da agulha

“…Já métodos de exérese como a nucleotomia percutânea manual ou automatizada também emergiram na década de 80, no entanto devido a estudos que mostraram resultados desencorajadores caíram em desuso (GOUPILLE et al, 2007) YIN et al, 2015). De maneira geral considerando os aspectos físicos, absorção muito baixa da luz pelos tecidos poderia resultar em vaporização insuficiente de água, enquanto que absorção muito alta poderia hiperaquecer e queimar as estruturas circunvizinhas, como a PTC ou as raízes nervosas (CHOY et al, 1991;CSELIK et al, 2012;NERUBAY;CASPI;LEVINKOPF, 1997;PLAPLER et al, 2016). (IWATSUKI et al, 2005).…”