Selective stimulation to modulate the sympathetic nervous system

Abstract

Systems, methods and devices are provided for the targeted treatment of a variety of medical conditions by directly neuromodulating a target anatomy associated with the condition while minimizing or excluding undesired neuromodulation of other anatomies. Typically, the target anatomy includes one or more dorsal root ganglia, dorsal roots, dorsal root entry zones, or portions thereof. Such target stimulation areas are utilized due in part to their effect on the sympathetic nervous system.

1 . A method of modulating a neural pathway in the sympathetic nervous system, comprising:
 positioning at least one electrode of a lead in close proximity to a dorsal root ganglion upstream of at least one ganglion of the sympathetic nerve chain; and   providing energy to the at least one electrode so as to neuromodulate the dorsal root ganglion in a manner that influences a condition associated with the at least one ganglion of the sympathetic nerve chain while excluding neuromodulation of an associated ventral root.   
     
     
         2 . The method according to  claim 1  wherein neuromodulating a dorsal root ganglion comprises neuromodulating a dorsal root ganglion in a manner that influences functional activation of a bodily system associated with the at least one ganglion along the sympathetic nerve chain. 
     
     
         3 . The method according to  claim 2  wherein neuromodulating a dorsal root ganglion comprises neuromodulating a dorsal root ganglion in a manner that influences functional activation of an organ associated with the at least one ganglion along the sympathetic nerve chain. 
     
     
         4 . The method according to  claim 1  wherein neuromodulating a dorsal root ganglion comprises neuromodulating a dorsal root ganglion in a manner that influences functional inhibition of a bodily system associated with the at least one ganglion along the sympathetic nerve chain. 
     
     
         5 . The method according to  claim 4  wherein neuromodulating a dorsal root ganglion comprises neuromodulating a dorsal root ganglion in a manner that influences functional inhibition of an organ associated with the at least one ganglion along the sympathetic nerve chain. 
     
     
         6 . The method according to  claim 1  wherein neuromodulating a dorsal root ganglion comprises neuromodulating a dorsal root ganglion in a manner that lessens vascular resistance of a blood vessel associated with the at least one ganglion along the sympathetic nerve chain. 
     
     
         7 . The method according to  claim 1  wherein neuromodulating a dorsal root ganglion comprises neuromodulating a dorsal root ganglion in a manner that improves vascular perfusion to an ischemic body region or tissue. 
     
     
         8 . The method according to  claim 1  wherein the condition comprises an ischemic disorder, diabetes, peripheral vascular disease, stroke, erectile dysfunction, a sympathetically maintained or mediate pain condition, Raynaud's disease, heart disease, angina pectoris, vascular disease, a skin ulceration, a wound healing disorder, asthma, hypertension, an immune system disorder or a renal disorder. 
     
     
         9 . The method according to  claim 1  wherein the at least one ganglion of the sympathetic nerve chain is a cervical ganglion. 
     
     
         10 . The method according to  claim 1  wherein the at least one ganglion of the sympathetic nerve chain is a thoracic ganglion. 
     
     
         11 . The method according to  claim 1  wherein the at least one ganglion of the sympathetic nerve chain is a lumbar ganglion. 
     
     
         12 . The method according to  claim 1  wherein the positioning step comprises positioning the at least one electrode on the dorsal root ganglion epinurium. 
     
     
         13 . The method according to  claim 1  further comprising directly applying stimulation to the at least one ganglion along the sympathetic nerve chain. 
     
     
         14 . The method according to  claim 13  wherein the directly applying stimulation step for the at least one ganglion along the sympathetic nerve chain is performed using an electrode exposed to the at least one ganglion along the sympathetic nerve chain. 
     
     
         15 . A method of modulating a portion of a neural pathway in the sympathetic nervous system, comprising:
 positioning at least one electrode of a lead in close proximity to a target dorsal root ganglion associated with the portion of the neural pathway; and   energizing the at least one electrode so that the portion of the neural pathway is altered and energy provided by the at least one electrode dissipates within the target dorsal root ganglion while excluding an associated ventral root.   
     
     
         16 . A method as in  claim 15 , wherein the energy provided by the at least one electrode selectively stimulates a soma and/or one of the ascending or descending axons within the target dorsal root ganglion which activates a premotor neuron. 
     
     
         17 . A method as in  claim 16 , wherein the activation of the premotor neuron acts upon a sympathetic motor neuron causing inhibition of the release of norephinephrine by the sympathetic motor neuron. 
     
     
         18 . A method as in  claim 16 , wherein the activation of the premotor neuron acts upon a sympathetic motor neuron causing inhibition of vascular resistance in a blood vessel influenced by the sympathetic motor neuron. 
     
     
         19 . A method as in  claim 15 , wherein the altering of the portion of the neural pathway increases perfusion to a region of the body associated with the portion of the neural pathway. 
     
     
         20 . A method as in  claim 19 , wherein the region of the body comprises a brain. 
     
     
         21 . A method as in  claim 19 , wherein the region of the body comprises an ischemic limb. 
     
     
         22 . A method as in  claim 19 , wherein the altering of the portion of the neural pathway increases perfusion to a portion of a peripheral vascular system affected by a peripheral vascular disease. 
     
     
         23 . A method as in  claim 15 , wherein the altering of the portion of the neural pathway alleviates sympathetically mediated pain or sympathetically maintained pain.