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

Author(s)

Plapler, Helio ^{[1, 2]} ; Mancini, Marilia W. ^[3] ; Sella, Valeria R. G. ^[1] ; Bomfim, Fernando R. C. ^[1]

Affiliation

^[1] Univ Fed Sao Paulo, Dept Surg, BR-04023900 Sao Paulo - Brazil

^[2] Rua Tomas Carvalhal, 884 Apt 51, BR-04006003 Sao Paulo, SP - Brazil

^[3] DMC Ltd, BR-13562030 Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Lasers in Medical Science; v. 31, n. 3, p. 421-428, APR 2016.
• Web of Science Citations: 1

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 (lambda = 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. (AU)

• FAPESP's process: 10/12607-9 - Use of different laser wavelengths to treat discal hernia (discectomy): new equipment operating at 2000nm
• Grantee: Helio Plapler
• Support Opportunities: Regular Research Grants