Method and system for photoselective vaporization of the prostate, and other tissue

Abstract

A method for photoselective vaporization of prostate tissue includes delivering laser radiation to the treatment area on the tissue, via an optical fiber for example, wherein the laser radiation has a wavelength and irradiance in the treatment area on the surface of the tissue sufficient because vaporization of a substantially greater volume of tissue than a volume of residual coagulated tissue caused by the laser radiation. The laser radiation is generated using a neodymium doped solid-state laser, including optics producing a second or higher harmonic output with greater than 60 watts average output power. The delivered laser radiation has a wavelength for example in a range of about 200 nm to about 650 nm, and has an average irradiance in the treatment area greater than about 10 kilowatts/cm 2 , in a spot size of at least 0.05 mm 2 .

1 . A method for vaporization of tissue, comprising:
 delivering laser radiation to a treatment area on the tissue, the laser radiation having a wavelength and having an average irradiance in the treatment area sufficient to cause vaporization of vascularized tissue at a vaporization rate that is substantially higher than a rate of coagulation of surrounding tissue.   
   
   
       2 . The method of  claim 1 , wherein said radiation causes a region of coagulation in the vascular tissue sufficient to prevent significant bleeding. 
   
   
       3 . The method of  claim 1 , including delivering said radiation using an optical fiber having a tip positioned near said tissue. 
   
   
       4 . The method of  claim 1 , wherein said radiation has a wavelength between 200 and 1000 nm. 
   
   
       5 . The method of  claim 1 , including delivering an irrigant to the tissue during said delivering laser radiation. 
   
   
       6 . The method of  claim 1 , including delivering an irrigant comprising water to the tissue during said delivering laser radiation, and wherein said laser radiation has a wavelength between 200 and 1000 nm. 
   
   
       7 . The method of  claim 1 , including delivering said radiation using an optical fiber having a side firing tip positioned near said tissue. 
   
   
       8 . An apparatus for photoselective vaporization of tissue, comprising:
 a laser producing laser radiation;   an endoscope, including an optical fiber coupled to the laser, adapted to direct laser radiation from the fiber, and a flow of irrigant to a treatment area on a surface of the tissue;   laser and optical fiber being adapted to deliver the laser radiation at a wavelength and an average irradiance in the treatment area sufficient to cause vaporization of vascular tissue at a vaporization rate that is substantially higher than a rate of coagulation of surrounding tissue.   
   
   
       9 . The apparatus of  claim 8 , wherein the optical fiber has a side firing tip adapted to be positioned near said tissue. 
   
   
       10 . A method for vaporization of tissue, comprising:
 generating laser radiation with an average power greater that 60 Watts;   coupling said laser radiation into an optical fiber having a tip;   positioning the tip of the optical fiber near a treatment area on vascular tissue;   delivering laser radiation to the treatment area using the optical fiber, the laser radiation having a wavelength and having average irradiance in the treatment area sufficient to cause vaporization of said vascular tissue at a vaporization rate that is substantially higher than a rate of coagulation of surrounding tissue; and   delivering an irrigant to the treatment area while delivering said laser radiation.   
   
   
       11 . The method of  claim 10 , wherein said radiation causes a region of coagulation in the vascular tissue sufficient to prevent significant bleeding. 
   
   
       12 . The method of  claim 10 , including delivering said radiation using an optical fiber having a side firing tip positioned near said tissue.