Clinical application of pulsed laser-induced liquid jet: Preliminary report in glioma surgery

Purpose: Both maximum resection of tumor and preservation of fine vessels are conflicting aims, but important factors to improve outcome in glioma surgery. Water jet dissection has been reported to dissect tissue while ensuring preservation of fine vessels. However, it was difficult to apply conventional water jet device in microsurgery due to the use of high pressure and continuous water a flow. To overcome these issues, we have developed pulsed holmium: yttrium-aluminum-garnet (YAG) laser-induced liquid jet (LILJ) for microsugical use and applied it in glioma surgery. Methods: LILJ was generated by irradiating pulsed Ho: YAG laser (3 Hz, pulse laser energy 233-300 mJ/pulse) within a stainless tube (outer diameter (OD): 1.26 mm inner diameter (ID): 0.90 mm) filled with cold (4°C) lactated Ringer's solution. The laser beam was conducted through optical quartz fiber (core diameter: 400 μm). The jet generated was ejected from a stainless nozzle (OD: 1.06 mm, ID: 0.70 mm). To avoid splash and air bubbles within the surgical held, the nozzle was placed inside a stainless suction tube (OD: 3.06 mm. ID: 2.64 mm). LILJ was ejected randomly toward blood vessels and tissue simultaneously after removal of arachnoid membrane by microsurgical technique, and the quality of the dissection and the visual field were evaluated in 4 patients with supratentorial glioma. Results: Restoration of small arteries (diameter: 100 to 200 microns) was accomplished. There was no significant occurrence of splash or air bubbles under the microscopic view. Conclusion: Present results showed that the pulsed LILJ system may safely be used for microsurgical procedures, and may be useful for glioma resection where preservation of fine vessels is required.