Laser prostatectomy is at present an established alternative for transurethral electroresection of the prostate (TUR-P). To compete with the different laser techniques, new electrosurgical modalities were developed as replacement for the standard electrosurgery tools for TUR-P. These modalities consist of a grooved cylinder fitted at the end of a TUR-P-element and are designed to combine both vaporization and coagulation in one device. The aim of this study was to investigate the potentials of the new 'rollerbar' devices and compare them with contact laser devices. Four different 'rollerbars' (Ciron, Storz and Prosurg), standard rollerball (Storz), and contact fibers (SLT) were applied to bovine myocard tissue submerged in glycine (electro) or saline (laser). The Valley Laboratory Force 40 and Force 300 were used as electrosurgical units; an MBB 4060 as Nd:YAG laser. Power settings ranged from 100 to 300 Watt (pure cut mode) for the electrosurgery device. The laser settings ranged from 10 to 60 Watt. The devices were moved over the tissue with a constant speed, while constant force was applied. The direct thermal effect of the devices was studied with a special thermal imaging technique on phantom tissue. Results show the vaporizing and coagulating power of the different devices. The rollerball (adjusted to high electrical power, i.e., 200 Watt) and the contact fibers provide similar vaporizing potential as the special-developed 'rollerbar' devices. Coagulation, necessary for hemostasis, is in all cases limited to a depth of about 2 mm. Increasing the electrical power from 200 to 300 watt only slightly increased the affected volume. The presented 'rollerbars' have a clear vaporizing and coagulating effect on tissue. The standard rollerball and contact laser fibers show similar capacities as the special-designed rollerbars.
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