Presentation Authors: Mark Taratkin*, Dmitry Enikeev, Petr Glybochko, Leonid Rapoport, Moscow, Russian Federation, Christopher Netsch, Benedikt Becker, Andreas J. Gross, Hamburg, Germany
Introduction: The interactions between the laser and tissue depend on the wavelength of the laser. Lasers affect the tissue via its relevant chromophores that absorb energy. In the prostate they are water for Ho:YAG, Tm:YAG and Tm-fiber lasers (TFL) and haemoglobin for the Greenlight (KTP) laser and blue diode laser (BDL). Combining the two lasers (TFL+BDL) with different target chromophores (water and hemoglobin) may have potential benefits for prostate surgery, namely less carbonization and faster vaporization. The aim of this study was to investigate the potential of a hybrid (TFL+BDL) laser vs. TFL and Ho:YAG lasers in vitro.
Methods: Fresh non-frozen porcine kidney was used as the model for the prostate to compare 3 lasers with an average power of 120W: a Ho:YAG laser, a TFL and a hybrid TFL+BDL (Table 1). In all cases, a 600 Âµm cleaved laser fiber was employed. A motorized XY translation stage with fixed fiber holder for control of cutting speed (2mm/s and 5 mm/s) was used. All samples were put in tissue holders with 0.5Â±0.1 mm gap between the fiber and tissue. Five incisions of kidney in saline solution with each laser were made. Lactate dehydrogenase (LDH) staining of the embedded specimens was performed to determine incision depth, zones of vaporization, zones of coagulation and visible carbonization rate (from 0 to 3).
Results: Laser properties, laser settings and pathology results are shown in Table 1. Hybrid laser (TFL+BDL) produced the deepest incisions and provided the fastest vaporization among the investigated lasers with little to no carbonization and limited coagulation depth. All these facts make it a perfect tool for tissue vaporization.
Conclusions: A hybrid TFL + BDL makes deeper and faster incisions than TFL and Ho:YAG lasers. Interestingly, it also produces a smaller carbonization zone and limits coagulation depth.