Neurostimulation methods and systems

Abstract

Some embodiments of the present invention provide stimulation systems and components for selective stimulation and/or neuromodulation of one or more dorsal root ganglia through implantation of an electrode on, in or around a dorsal root ganglia. Some other embodiments of the present invention provide methods for selective neurostimulation of one or more dorsal root ganglia as well as techniques for applying neurostimulation to the spinal cord. Still other embodiments of the present invention provide stimulation systems and components for selective stimulation and/or neuromodulation of one or more dorsal root ganglia through implantation of an electrode on, in or around a dorsal root ganglia in combination with a pharmacological agent.

What is claimed is: 
     
         1 . A method of maintaining a paresthesia intensity value in a patient receiving a neuromodulation stimulation therapy on a targeted neural tissue of a spinal level, comprising:
 accessing a percutaneous space of the patient on the spinal level lateral to the targeted neural tissue on the spinal level;   laterally advancing a lead comprising at least one electrode into a position for delivery of an electrical signal related to the neuromodulation stimulation therapy on the targeted neural tissue;   implanting the lead in the position;   connecting the lead to an implantable pulse generator;   operating a stimulation program in the implantable pulse generator for delivery of the electrical signal;   maintaining a first paresthesia intensity value related to the neuromodulation stimulation therapy on the targeted neural tissue while the patient is in an upright position; and   maintaining a second paresthesia intensity value related to the neuromodulation stimulation therapy on the targeted neural tissue while the patient is in a supine position, wherein there is no clinical significance in a difference between the first paresthesia intensity value and the second paresthesia intensity value.   
     
     
         2 . The method of  claim 1  wherein the targeted neural tissue is a dorsal root ganglion on the spinal level. 
     
     
         3 . The method of  claim 1  wherein the targeted neural tissue comprises a first dorsal root ganglion and a second dorsal root ganglion and the accessing step, the laterally advancing step and the implanting step are performed on the first dorsal root ganglion on a first spinal level and the accessing step, the laterally advancing step and the implanting step are performed on the second dorsal root ganglion on a second spinal level. 
     
     
         4 . The method of  claim 3  wherein the first spinal level and the second spinal level are adjacent spinal levels without an intervening spinal level. 
     
     
         5 . The method of  claim 3  wherein at least one of the first spinal level and the second spinal level is a spinal level in a cervical spine. 
     
     
         6 . The method of  claim 3  wherein at least one of the first spinal level and the second spinal level is a spinal level in a thoracic spine. 
     
     
         7 . The method of  claim 3  wherein at least one of the first spinal level and the second spinal level is a spinal level in a lumbar spine. 
     
     
         8 . The method of  claim 3  further comprising: selecting the first spinal level and the second spinal level so that the first paresthesia intensity value and the second paresthesia intensity value relate to a dermatome of a cervical spine. 
     
     
         9 . The method of  claim 3  further comprising: selecting the first spinal level and the second spinal level so that the first paresthesia intensity value and the second paresthesia intensity value relate to a dermatome of a thoracic spine. 
     
     
         10 . The method of  claim 3  further comprising: selecting the first spinal level and the second spinal level so that the first paresthesia intensity value and the second paresthesia intensity value relate to a dermatome of a lumbar spine. 
     
     
         11 . The method of  claim 3  wherein the second dorsal root ganglion is on the same side of the spinal cord as the first dorsal root ganglion. 
     
     
         12 . The method of  claim 3  wherein the second dorsal root ganglion on the opposite side of the spinal cord as the first dorsal root ganglion. 
     
     
         13 . A method of treating chronic pain in a patient by maintaining a paresthesia intensity and distribution by stimulating a first dorsal root ganglion on a first spinal level of a vertebral column, comprising:
 implanting an elongated probe within the patient, wherein the implanting comprises advancing a distal end of the elongated probe from a position outside of the vertebral column and an epidural space of the vertebral column through a vertebral foramen to position one or more electrodes of the probe adjacent to the first dorsal root ganglion such that a portion of the probe immediately proximal to the one or more electrodes is exiting the vertebral foramen;   operating pulse generating circuitry implanted in the patient to provide electrical pulses to selectively stimulate the first dorsal root ganglion to treat the chronic pain of the patient by maintaining a first paresthesia intensity and distribution before an activity;   operating pulse generating circuitry implanted in the patient to provide electrical pulses to selectively stimulate the first dorsal root ganglion to treat the chronic pain of the patient by maintaining a second paresthesia intensity and distribution during the activity; and   operating pulse generating circuitry implanted in the patient to provide electrical pulses to selectively stimulate the first dorsal root ganglion to treat the chronic pain of the patient by maintaining a third paresthesia intensity and distribution after the activity, wherein the differences between the first paresthesia intensity and distribution, the second paresthesia intensity and distribution and the third paresthesia intensity and distribution are not clinically significant.   
     
     
         14 . The method of  claim 13  wherein the first dorsal root ganglion is selected to treat chronic pain of the patient related to a dermatome of a cervical spine. 
     
     
         15 . The method of  claim 13  wherein the first dorsal root ganglion is selected to treat chronic pain of the patient related to a dermatome of a thoracic spine. 
     
     
         16 . The method of  claim 13  wherein the first dorsal root ganglion is selected to treat chronic pain of the patient related to a dermatome of a lumbar spine.