System and method for optogenetic therapy
Configurations are described for utilizing light-activated proteins within cell membranes and subcellular regions to assist with medical treatment paradigms, such as hypertension treatment via anatomically specific and temporally precise modulation of renal plexus activity. The invention provides for proteins, nucleic acids, vectors and methods for genetically targeted expression of light-sensitive proteins to specific cells or defined cell populations. In particular the invention provides systems, devices, and methods for millisecond-timescale temporal control of certain cell activities using moderate light intensities, such as the generation or inhibition of electrical spikes in nerve cells and other excitable cells.
1. A method for injecting a targeted tissue structure, comprising:
a. selecting the targeted tissue structure to be injected;
b. providing an elongate flexible injection member having a surface biased to assume an arcuate geometric configuration when released, the injection member comprising an array of injection needles fixed relative to the surface and being configured to assume a substantially straight geometric configuration based upon an input from an operator manipulating a remote actuator that is operatively coupled to the elongate flexible injection member;
c. causing the elongate flexible injection member to assume the substantially straight configuration based upon an input from the operator;
d. navigating the elongate flexible injection member into a position relative to the targeted tissue structure such that upon release of the input, the flexible injection member will be biased to return to the arcuate geometric configuration, and in reconfiguring toward the arcuate configuration, portions of the elongate flexible member will advance a plurality of the injection needles into the targeted tissue structure and remain biased to stay advanced therein until a further input causes the elongate flexible injection member to re-assume the substantially straight configuration;
e. releasing the input to advance the plurality of the injection needles into the targeted tissue structure; and
f. injecting the targeted tissue structure using the plurality of needles advanced into the targeted tissue structure.
2. The method of claim 1 , wherein selecting the targeted tissue structure to be injected comprises imaging the target tissue using a modality selected from the group consisting of: radiography, fluoroscopy, ultrasound, magnetic resonance imaging, computed tomography imaging, and endoscopy.
3. The method of claim 1 , wherein the arcuate configuration comprises a substantially constant radius of curvature.
4. The method of claim 1 , wherein the arcuate configuration comprises an irregularly arcuate geometric configuration.
5. The method of claim 1 , wherein the elongate flexible injection member comprises a bending spine member configured to urge the elongate flexible injection member into the arcuate configuration when unloaded.
6. The method of claim 5 , wherein the bending spine member comprises a shape-memory superalloy.
7. The method of claim 5 , wherein the elongate flexible injection member further comprises a mechanical straightening bladder which may be pressurized based upon the input from the operator to overcome loads applied by the bending spine member and urge the elongate flexible injection member into the substantially straight geometric configuration, and wherein causing the elongate flexible injection member to assume the substantially straight configuration comprises increasing the pressure within the mechanical straightening bladder.
8. The method of claim 7 , wherein the remote actuator comprises a straightening pressure reservoir pressurized by the operator, the straightening pressure reservoir fluidly coupled to the mechanical straightening bladder by a fluid conduit, and wherein increasing the pressure within the mechanical straightening bladder comprises increasing the pressure within the straightening pressure reservoir.
9. The method of claim 1 , wherein the elongate flexible injection member has a substantially rectangular form when viewed in the substantially straight configuration.
10. The method of claim 1 , wherein the arcuate geometric configuration comprises a circular shape.
11. The method of claim 1 , wherein the arcuate geometric configuration comprises an at least partially helical shape.
12. The method of claim 1 , wherein injecting the targeted tissue structure comprises increasing pressure within an injection fluid reservoir fluidly coupled to the array of injection needles.
13. The method of claim 1 , wherein tips of the array of injection needles are coplanar when the elongate flexible injection member is in the substantially straight configuration.
14. The method of claim 1 , further comprising movably coupling the elongate flexible injection member through a lumen defined through an elongate delivery conduit so that the elongate flexible injection member may be delivered atraumatically.
15. The method of claim 14 , wherein the elongate delivery conduit comprises a catheter.
16. The method of claim 15 , wherein the catheter is a remotely steerable catheter comprising one or more steering elements which may be proximally manipulated to cause controlled bending in the catheter, the method further comprising manipulating the one of more steering elements to navigate the catheter, thereby navigating the elongate flexible injection member.
17. The method of claim 14 , further comprising an elongate delivery member coupled to the delivery conduit and configured to facilitate creation of relative motion between the elongate flexible injection member and the elongate delivery conduit during placement of the elongate flexible injection member, the method further comprising moving the elongate delivery member relative to the delivery conduit to at least partially remove the elongate flexible injection member from the delivery conduit.
18. The method of claim 17 , wherein the elongate delivery member comprises a flexible shaft configured to bend in compliance with bending of the elongate delivery conduit.
19. The method of claim 18 , wherein the flexible shaft comprises a polymeric material.