Minimally invasive implantable neurostimulation system

Abstract

A medical device system for delivering a neuromodulation therapy includes a delivery tool for deploying an implantable medical device at a neuromodulation therapy site. The implantable medical device includes a housing, an electronic circuit within the housing, and an electrical lead comprising a lead body extending between a proximal end coupled to the housing and a distal end extending away from the housing and at least one electrode carried by the lead body. The delivery tool includes a first cavity for receiving the housing and a second cavity for receiving the lead. The first cavity and the second cavity are in direct communication for receiving and deploying the housing and the lead coupled to the housing concomitantly as a single unit.

1 . A medical device system for delivering a neuromodulation therapy, comprising:
 an implantable medical device comprising:
 a housing; 
 an electronic circuit within the housing; 
 an electrical lead comprising a lead body extending between a proximal end coupled to the housing and a distal end extending away from the housing and at least one electrode carried by the lead body; and 
   a delivery tool for deploying the implantable medical device at a neuromodulation therapy site, the tool comprising a first cavity for receiving the housing and a second cavity for receiving the lead, the first cavity and the second cavity in direct communication for receiving the housing and the lead coupled to the housing as a single unit.   
     
     
         2 - 17 . (canceled) 
     
     
         18 . A method for delivering an implantable medical device to a neuromodulation therapy site, comprising:
 positioning a implantable medical device housing coupled to an electrical lead in a delivery tool as a single unit; and   deploying the housing and the lead from the delivery tool concomitantly as a single unit to the therapy site,   the housing enclosing an electronic circuit,   the electrical lead comprising a lead body extending between a proximal end coupled to the housing and a distal end extending away from the housing and at least one electrode carried by the lead body,   the delivery tool comprising a first cavity for receiving the housing and a second cavity for receiving the lead, the first cavity and the second cavity in direct communication with each other for receiving the housing and the lead coupled to the housing as a single unit.   
     
     
         19 . The method of  claim 18 , further comprising deploying the housing and the lead to position a flattened side of the lead against a tissue layer. 
     
     
         20 . The method of  claim 18 , further comprising positioning a first fixation member in the tool to extend through an open side of the tool, the first fixation member extending from the distal end of the lead body. 
     
     
         21 . The method of  claim 20 , further comprising:
 positioning a second fixation member in the tool to extend through an open side of the tool, the second fixation member being spaced apart proximally from the first fixation member along the lead body; and   capturing a tissue layer between the first fixation member and the second fixation member when the lead distal end is advanced through a tissue layer.   
     
     
         22 . The method of  claim 18 , further comprising inserting a distal tool end through a tissue layer to implant the lead distal end beneath the tissue layer, the housing remaining superficially to the tissue layer. 
     
     
         23 . The method of  claim 18 , wherein positioning the single unit comprises:
 positioning the housing in a tool first shaft portion extending from a tool handle portion, the tool first shaft portion comprising a side wall defining the first cavity; and   positioning the lead in an open-sided, hollow needle of a tool second shaft portion extending from the tool first shaft portion to a distal tool end and defining the second cavity for receiving the lead;   the single unit extending through a distal opening of the first shaft portion in direct communication with the open-sided lumen of the second shaft portion.   
     
     
         24 . The method of  claim 23 , further comprising moving a cover of the tool to retain the housing and the lead within the tool after positioning the housing and the lead in the tool, the cover fitting over at least a portion of one of the first shaft portion and the second shaft portion. 
     
     
         25 . The method of  claim 18 , wherein positioning the single unit comprises:
 positioning the housing in a proximal device guiding portion of a syringe body of the delivery tool, the device guiding portion defining the first cavity for receiving the housing and extending between a proximal end of the syringe body and a distal needle guiding portion of the syringe body, the distal needle guiding portion comprising an open sided lumen; and   positioning the lead in a distal hollow needle of a delivery tool plunger, the distal hollow needle comprising an open-sided lumen defining the second cavity for receiving the lead, the distal hollow needle extending through the needle guiding portion of the syringe body between a proximal plunger end and a distal plunger end,   the plunger further comprising a proximal shaft and a mid-portion extending from the proximal shaft through the device guiding portion to the distal hollow needle,   wherein deploying the housing and the lead comprises advancing the plunger through the syringe body to advance the distal hollow needle out a distal end of the distal needle guiding portion and the housing out a distal opening of the device guiding portion.   
     
     
         26 . The method of  claim 25 , further comprising positioning a fixation member coupled to the lead to extend through an open groove of the needle guiding portion of the syringe body as the plunger is advanced. 
     
     
         27 . The method of  claim 18 , further comprising deploying a housing fixation member to anchor the housing at the therapy site. 
     
     
         28 . The method of  claim 27 , wherein deploying the housing fixation member comprises one of:
 advancing a flanged post through an aperture of the housing,   rotating a hook coupled to the housing into a tissue layer;   advancing descending legs coupled to a cross-beam into a tissue layer to capture the housing between the tissue layer and the cross-beam,   enclosing the housing in a shroud to which the housing fixation member is coupled,   advancing a serrated body through an aperture of the housing and fixedly engaging the serrated body with ratcheting collet, and   advancing a U-shaped clip through an aperture of the housing.   
     
     
         29 . The method of  claim 27 , further comprising deploying a housing fixation member comprising a bioabsorbable material. 
     
     
         30 . The method of  claim 27 , further comprising deploying a housing fixation member comprising a shape memory alloy. 
     
     
         31 . The method of  claim 27 , further comprising deploying a housing fixation member comprising an electrode. 
     
     
         32 . The method of  claim 27 , wherein deploying the housing fixation member comprises anchoring a major side of the housing against a tissue layer, the major side comprising an electrode electrically coupled to the electronic circuitry. 
     
     
         33 . The method of  claim 18 , further comprising delivering test stimulation pulses using an electrode along a distal end of the delivery tool to identify the therapy site. 
     
     
         34 . The method of  claim 18 , further comprising coupling the lead to the housing to be non-removable from the housing.