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 photoselective vaporization of tissue, comprising: 
 delivering laser radiation to a treatment area on the tissue, the laser radiation having a wavelength and having irradiance in the treatment area sufficient to cause vaporization of a substantially greater volume of tissue than a volume of residual coagulated tissue caused by the laser radiation.    
   
   
       2 . A method for treating benign prostatic hypertrophy (BPH), comprising the steps of: 
 providing a solid-state laser emitting light with a wavelength of 200 to 1000 nm having a laser element positioned to receive pump radiation from a pump radiation source;    modulating the pump radiation source to cause the laser element to emit laser light having pulse duration between 0.1 and 500 milliseconds and pulse frequencies between 1 and 500 Hz; and    delivering the laser light to targeted tissue.    
   
   
       3 . A method for treating benign prostatic hypertrophy (BPH), comprising the steps of: 
 providing a solid-state laser having laser element positioned to receive pump radiation from a pump radiation source;    Q-switching the laser to generate a quasi-continuous beam having an output power exceeding 60 watts, and    delivering the beam to targeted prostate tissue.    
   
   
       4 . The method of  claim 3  wherein the output power is 80 watts or greater.  
   
   
       5 . A method comprising: 
 hemostatically irradiating soft tissue with coherent radiation from a laser having a pump radiation source that does not produce enough heat in a lasing element to create a significant amount of thermal lensing in the lasing element; and    a power and wavelength such that the radiation is preferentially absorbed by the tissue rather than a fluid.    
   
   
       6 . 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 irradiance in the treatment area sufficient to cause vaporization of a substantially greater volume of tissue than a volume of residual coagulated tissue caused by the laser radiation.