Inducing vasodilation

Abstract

A method for inducing dilation of a blood vessel, e.g., of an obstructed blood vessel, includes irradiating the vessel with a pulse of light or its equivalent at a low energy fluence.

1 . A method for inducing dilation of a blood vessel, comprising subjecting the vessel to a shock wave equivalent to irradiating the vessel with a pulse of light at an energy fluence below the energy fluence threshold for causing vasoconstriction in such a vessel.  
     
     
         2 . A method for inducing dilation of a blood vessel, comprising irradiating the vessel with a pulse of light at a low energy fluence.  
     
     
         3 . The method of  claim 2  comprising irradiating the vessel with a succession of pulses of light, each at a low energy fluence.  
     
     
         4 . The method of  claim 1 ,  2  or  3  wherein each said pulse of light has an energy fluence below the threshold for inducing vasospasm.  
     
     
         5 . The method of  claim 1 ,  2  or  3  wherein each said pulse of light has an energy fluence below the threshold for thermally damaging the wall of the vessel.  
     
     
         6 . The method of  claim 1 ,  2  or  3  wherein each said pulse of light has an energy fluence between 1 and 30 J/cm.  
     
     
         7 . The method of  claim 6  wherein each said pulse of light has an energy fluence less than about 10 J/cm 2 .  
     
     
         8 . The method of  claim 7  wherein each said pulse of light has an energy fluence less than about 5 J/cm 2 .  
     
     
         9 . The method of  claim 2 , or  3  wherein the step of irradiating the vessel with a pulse of light comprises directing a beam of light onto the vessel.  
     
     
         10 . The method of  claim 9  wherein said beam of light is generated by a laser.  
     
     
         11 . The method of  claim 9  wherein said beam of light is generated by a pulsed laser.  
     
     
         12 . The method of  claim 9  wherein the step of directing said beam of light comprises directing said light through a light guide.  
     
     
         13 . The method of  claim 9  wherein the step of directing said beam of light comprises directing said light through a fiber optic bundle.  
     
     
         14 . The method of  claim 1 ,  2 , or  3 , further comprising the step of administering a pharmaceutical dilator following said step of irradiating said vessel.  
     
     
         15 . The method of  claim 1 ,  2 , or  3 , further comprising carrying out a transluminal angioplasty in the vessel near the site of irradiating.  
     
     
         16 . The method of  claim 1 ,  2 , or  3 , further comprising carrying out a thrombolysis in the vessel near the site of irradiating.  
     
     
         17 . The method of  claim 1 ,  2 , or  3  wherein the duration of each said pulse is between about 250 nanoseconds and 300 microseconds.  
     
     
         18 . The method of  claim 17  wherein said duration is between 500 nanoseconds and 100 microseconds.  
     
     
         19 . The method of  claim 17  wherein the duration of each said pulse is about 1 microsecond.