Application of holmium:YAG laser in epiduroscopy: extended practicabilities in the treatment of chronic back pain syndrome.

Abstract

OBJECTIVE Minimally invasive and endoscopic techniques offer advantages in the treatment of chronic back pain syndrome and may provide for expanded indications and visualization. Epiduroscopy for the visualization of the epidural space still is burdened with technical problems. The mechanical instruments now available, coupled with the narrow working canal, result in marked limitations. The aim of this study was to assess the possibilities and technical requisites for the use of the holmium:YAG laser in lumbar epiduroscopy. BACKGROUND DATA Epiduroscopy has been used for visualization of the lumbar epidural space since the 1930s. Studies have been performed to evaluate the effects and possibilities of epiduroscopy in chronic back pain. Most of them only describe the anatomical aspects. MATERIALS AND METHODS Forty-seven patients were epiduroscopied and treated, for findings of corresponding epidural adhesions, with the holmium:YAG laser. The examinations concentrated on the general applicability of the holmium:YAG laser in epiduroscopy and the technical parameters necessary for this procedure. The clinical evaluation of therapy was made prospectively in comparison with the preoperative status and compared to already recorded groups in previous studies. RESULTS Bending behavior without negative impact of the epiduroscope was only attained with laser fibers less than 300 microm, so a fiber with a diameter of 265 microm was used as the standard. The minimum energy output of the laser required for an adequate ablative effect was 0.8 J at a frequency of 8 Hz. The total energy output was 0.256-1.4 kJ. Complications did not occur intraoperatively nor following the procedure. The follow-up examinations showed no deterioration of the complaints in any patient. There was no occurrence of relevant laser-related edemas or adhesions. The proportion of painful conditions that could be positively influenced corresponded to that in a control group treated only by mechanical means. CONCLUSION The results show that the holmium:YAG laser considerably expands therapeutic possibilities and aids in solving the technical problems of epiduroscopy. No negative effects occurred when the laser is used.