Methods and systems for intracranial neurostimulation and/or sensing

Abstract

Methods and systems for intracranial neurostimulation and/or sensing are disclosed. An intracranial signal transmission system in accordance with an embodiment of the invention includes a generally electrically insulating support body having a head portion configured to be positioned at least proximate to an outer surface of a patient's skull, and a shaft portion configured to extend into an aperture in the patient's skull. The system can further include at least one electrical contact portion carried by the support body. The at least one electrical contact portion can be positioned to transfer electrical signals to, from, or both to and from the patient's brain via the aperture in the patient's skull.

1 . An intracranial signal transmission system, comprising: 
 a generally electrically insulating support body having a head portion configured to be positioned at least proximate to an outer surface of a patient's skull, the support body further having a shaft portion configured to extend into an aperture in the patient's skull; and    at least one electrical contact portion carried by the support body, the at least one electrical contact portion being positioned to transfer electrical signals to, from, or both to and from the patient's brain via the aperture in the patient's skull.    
     
     
         2 . The system of  claim 1  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion, and wherein the system further comprises: 
 a signal transmitter operatively coupled to the first electrical contact portion to provide stimulation signals to the patient's brain; and    a sensor operatively coupled to the second electrical contact portion to receive signals from the patient's brain.    
     
     
         3 . The system of  claim 1  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion.  
     
     
         4 . The system of  claim 1 , further comprising: 
 an electrical signal transmitter; and    a generally continuous electrical signal path connected between the electrical signal transmitter and the at least one electrical contact portion.    
     
     
         5 . The system of  claim 1 , further comprising: 
 an electrical signal transmitter; and    an electrical signal path having a releasable connection at the electrical signal transmitter and being continuous between the releasable connection and the at least one electrical contact portion.    
     
     
         6 . The system of  claim 1  wherein the at least one electrical contact portion includes a first electrical contact portion coupleable to at least one signal transmitter to receive first electrical signals, and a second electrical contact portion coupleable to at least one signal transmitter to receive second electrical signals independent of the first electrical signals.  
     
     
         7 . An intracranial signal transmission system, comprising: 
 an electrical contact portion configured to be positioned in an aperture of a patient's skull; and    an electrical energy transfer device configured to be releasably positioned external to the patient's scalp, the energy transfer device being coupleable to a signal transmitter to transmit signals to the electrical contact portion while the electrical contact portion is positioned beneath the patient's scalp and while the energy transfer device is positioned external to the patient's scalp.    
     
     
         8 . The system of  claim 7  wherein the electrical energy transfer device includes: 
 a flexible outer layer;    an adhesive gel layer positioned to contact the patient's scalp;    a conductive layer positioned between the outer layer and the adhesive gel layer; and    a conductive lead connected to the conductive layer.    
     
     
         9 . The system of  claim 7  wherein the electrical contact portion includes a first electrical contact portion and wherein the system further comprises: 
 a second electrical contact portion spaced apart from the first electrical contact portion;    a signal transmitter operatively coupled to the first electrical contact portion to provide stimulation signals to the patient's brain; and    a sensor operatively coupled to the second electrical contact portion to receive signals from the patient's brain.    
     
     
         10 . The system of  claim 7  wherein the electrical contact portion includes a first electrical contact portion and wherein the system further comprises a second electrical contact portion spaced apart from the first electrical contact portion.  
     
     
         11 . The system of  claim 7 , further comprising: 
 an electrical signal transmitter; and    a generally continuous electrical signal path connected between the electrical signal transmitter and the at least one electrical contact portion.    
     
     
         12 . The system of  claim 7  wherein the electrical contact portion includes a first electrical contact portion coupleable to at least one signal transmitter to receive first electrical signals, and wherein the system further comprises a second electrical contact portion coupleable to at least one signal transmitter to receive second electrical signals independent of the first electrical signals.  
     
     
         13 . The system of  claim 7  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion, the first electrical contact portion having a first position relative to the support body so as to be positioned beneath the scalp by a first distance, the second electrical contact portion having a second position relative to the support body so as to be positioned beneath the scalp by a second distance greater than the first distance.  
     
     
         14 . An intracranial signal transmission system, comprising: 
 a shaft configured to extend through an aperture in a patient's skull;    a head connected to the shaft, the head being configured to be positioned adjacent to an external surface of the patient's skull, the head being eccentrically positioned relative to the shaft and having a first portion extending outwardly from the shaft by a first distance and a second portion extending outwardly from the shaft by a second distance different than the first distance; and    an electrical contact portion carried by at least one of the shaft and the head.    
     
     
         15 . The system of  claim 14 , further comprising an insert having an outer surface and aperture, the aperture being sized to receive the shaft, the outer surface having at least one securement element configured to secure the insert to the patient's skull.  
     
     
         16 . The system of  claim 14 , further comprising an insert having an outer surface and aperture, the aperture being sized to receive the shaft, the outer surface having threads configured to secure the insert to the patient's skull.  
     
     
         17 . An intracranial signal transmission system, comprising: 
 a shaft having an external surface configured to extend through an aperture in a patient's skull;    a head connected to the shaft and having a generally conical shape, with an angle between the external surface of the shaft and an external surface of the head being obtuse, and with the external surface of the head being configured to contact the walls of the aperture in the patient's skull; and    an electrical contact portion carried by at least one of the shaft and the head.    
     
     
         18 . The system of  claim 17  wherein the shaft has a first end surface and the head has a second end surface facing generally opposite form the first end surface, and wherein the second end surface is positioned to be flush with an outer surface of the patient's skull.  
     
     
         19 . The system of  claim 17  wherein the shaft has a first end surface and the head has a second end surface facing generally opposite form the first end surface, and wherein the second end surface is positioned to project outwardly from an outer surface of the patient's skull.  
     
     
         20 . The system of  claim 17  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion, and wherein the system further comprises: 
 a signal transmitter operatively coupled to the first electrical contact portion to provide stimulation signals to the patient's brain; and    a sensor operatively coupled to the second electrical contact portion to receive signals from the patient's brain.    
     
     
         21 . The system of  claim 17  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion.  
     
     
         22 . The system of  claim 17 , further comprising: 
 an electrical signal transmitter; and    a generally continuous electrical signal path connected between the electrical signal transmitter and the at least one electrical contact portion.    
     
     
         23 . An intracranial signal transmission system, comprising: 
 a shaft configured to extend through an aperture in a patient's skull, the shaft having an external surface with a plurality of surface features positioned to receive growing bone tissue from the patient's skull;    a head connected to the shaft; and    an electrical contact portion carried by at least one of the shaft and the head.    
     
     
         24 . The system of  claim 23  wherein the surface features are recessed from the external surface of the shaft.  
     
     
         25 . The system of  claim 23  wherein the surface features include pores.  
     
     
         26 . The system of  claim 23  wherein the surface features include pores recessed from the external surface and, and wherein walls of the pores are positioned to be out of contact with walls of the aperture in the patient's skull as the shaft is positioned in the aperture.  
     
     
         27 . The system of  claim 23  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion, the first electrical contact portion having a first position relative to the head so as to be positioned beneath the scalp by a first distance, the second electrical contact portion having a second position relative to the head so as to be positioned beneath the scalp by a second distance greater than the first distance.  
     
     
         28 . An intracranial signal transmission system, comprising: 
 a shaft configured to extend through an aperture in a patient's skull;    a head connected to the shaft;    an electrical contact portion carried by at least one of the shaft and the head;    a radio frequency transponder carried by at least one of the shaft; and    at least one securement feature depending from at least one of the head and the shaft and being positioned to secure at least one of the head and the shaft to the patient's skull.    
     
     
         29 . The system of  claim 28 , further comprising: 
 a signal transmitter coupled to the electrical contact portion with a signal link;    a radio frequency receiver configured to receive signals from the transponder, the radio frequency receiver being coupled to the signal transmitter to control signals transmitted to the electrical contact portion based on signals received from the transponder.    
     
     
         30 . The system of  claim 28  wherein the shaft and the head are formed from a generally electrically insulating material.  
     
     
         31 . The system of  claim 28 , further comprising a radio frequency receiver configured to receive signals from the transponder.  
     
     
         32 . A method for installing an electrical contact portion in a patient's skull, comprising: 
 drilling a hole in a patient's skull;    determining a distance from an outer surface of the patient's skull to a feature beneath the outer surface of the patient's skill by inserting an elongated member having graduation makings into the pilot hole;    selecting a size of an intracranial electrode based on the distance determined with the elongated member;    inserting the intracranial electrode into the hole; and    securing the intracranial electrode to the patient's skull.    
     
     
         33 . The method of  claim 32  wherein drilling a hole includes drilling a pilot hole, and wherein the method further comprises increasing a diameter of the hole prior to inserting the intracranial electrode into the hole.  
     
     
         34 . A method for transmitting intracranial electrical signals, comprising: 
 positioning a generally electrically insulating support body proximate to a patient;    inserting a shaft portion of the support body into an aperture in the patient's skull;    positioning a head portion of the support body at least proximate to an outer surface of a patient's skull; and    transmitting electrical signals to, from or both to and from the patient's brain through the aperture in the patient's skull via at least one electrical contact portion carried by the support body.    
     
     
         35 . The method of  claim 34  wherein transmitting electrical signals includes transmitting electrical stimulation signals to a first electrical contact portion carried by the support body and receiving sensor signals from a second electrical contact portion carried by the support body, the second electrical contact portion being spaced apart from the first electrical contact portion.  
     
     
         36 . The method of  claim 34  wherein transmitting signals via at least one electrical contact portion includes transmitting signals via a first electrical contact portion carried by the support body and a second electrical contact portion carried by the support body, the second electrical contact portion being spaced apart from the first electrical contact portion.  
     
     
         37 . The method of  claim 34  wherein transmitting signals includes transmitting signals along a generally continuous electrical signal path connected between an electrical signal transmitter and the at least one electrical contact portion.  
     
     
         38 . The method of  claim 34  wherein transmitting signals via at least one electrical contact portion includes transmitting a first electrical signal via a first electrical contact portion carried by the support body and transmitting a second electrical signal via a second electrical contact portion carried by the support body, the second electrical contact portion being spaced apart from the first electrical contact portion, the first signal being independent of the second signal.  
     
     
         39 . The method of  claim 34  wherein the support body carries a first electrical contact portion and a second electrical contact portion, and wherein inserting a shaft portion of the support body includes positioning the first electrical contact portion a first distance beneath the scalp and positioning the second electrical contact portion a second distance beneath the scalp, the second distance being greater than the first distance.  
     
     
         40 . A method for transmitting intracranial electrical signals, comprising: 
 disposing an electrode within an aperture in a patient's skull;    releasably positioning an electrical transmission device at least proximate to an external surface of the patient's scalp; and    transmitting an electrical signal through the patient's scalp between the electrode and the electrical transmission device.    
     
     
         41 . The method of  claim 40 , further comprising drilling the aperture in the patient's skull.  
     
     
         42 . The method of  claim 40 , further comprising adhering the electrical transmission device to the patient's scalp and wherein transmitting an electrical signal includes transmitting an electrical signal from a conductive layer positioned between an adhesive layer and a flexible outer layer of the electrical transmission device.  
     
     
         43 . The method of  claim 40  wherein transmitting an electrical signal includes transmitting a stimulation signal through the patient's scalp to the electrode.  
     
     
         44 . The method of  claim 40  wherein transmitting an electrical signal includes transmitting a sensor signal from the electrode through the patient's scalp.  
     
     
         45 . A method for installing an intracranial signal transmission system, comprising: 
 positioning an electrical contact portion of the system proximate to the patient's head, the electrical contact portion being carried by a support body having a shaft portion and a head portion positioned eccentrically relative to the shaft portion;    inserting the shaft portion into an aperture in the patient's skull;    positioning at least some of the head portion external to the patient's skull;    orienting the head portion so that a first part of the head portion extends outwardly from the shaft by a first distance and a second part of the head portion extends outwardly from the shaft by a second distance different than the first distance; and    transmitting an electrical signal via the electrical contact portion.    
     
     
         46 . The method of  claim 45  wherein the electrical contact portion is a first electrical contact portion, the support body is a first support body, and the aperture is a first aperture, and wherein the method further comprises: 
 positioning a head portion of a second support body proximate to the patient's head, the second support body carrying a second electrical contact portion, the head portion of the second support body including a first part that extends outwardly from the shaft by a first distance and a second part that extends outwardly from the shaft by a second distance different than the first distance;    inserting a shaft of the second support body into a second aperture in the patient's skull, the second aperture being spaced apart from the first aperture; and    orienting a head portion of the second support body so that the first part of the head portion of the second support body is positioned toward the first part of the head portion of the second support body.    
     
     
         37 . The method of  claim 45 , further comprising: 
 placing an insert into the aperture in the patient's skull;    placing the shaft of the support body in the an insert; and    securing the shaft to the insert.    
     
     
         48 . A method for installing an intracranial signal transmission system, comprising: 
 forming an aperture in a patient's skull, the aperture having first generally conical portion with a first diameter at an external surface of the patient's skull, and a second portion with a second diameter smaller than the first diameter beneath the external surface;    disposing proximate to the aperture an electrical contact portion carried by a support body having a shaft and a head depending from the shaft, the head having generally conical shape, with an angle between an external surface of the shaft and an external surface of the head being obtuse; and    inserting the support body into the aperture so that the shaft extends through the second portion of the aperture and the head engages a wall of the aperture at the first portion of the aperture.    
     
     
         49 . The method of  claim 48  wherein the shaft has a first end surface and the head has a second end surface facing generally opposite form the first end surface, and wherein inserting the support body includes inserting the support body so that the second end surface is flush with the outer surface of the patient's skull.  
     
     
         50 . The method of  claim 48  wherein the shaft has a first end surface and the head has a second end surface facing generally opposite form the first end surface, and wherein inserting the support body includes inserting the support body so that the second end surface is positioned to project outwardly from the outer surface of the patient's skull.  
     
     
         51 . The method of  claim 48  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion, and wherein the method further comprises: 
 transmitting a stimulation signal to the patient's brain via the first electrical contact portion; and    receiving a sensor signal from the patient's brain via the second electrical contact portion.    
     
     
         52 . The method of  claim 48  wherein the at least one electrical contact portion includes a first electrical contact portion and a second electrical contact portion spaced apart from the first electrical contact portion, and wherein the method further comprises: 
 transmitting a first stimulation signal to the patient's brain via the first electrical contact portion; and    transmitting a second stimulation signal to the patient's brain via the second electrical contact portion.    
     
     
         53 . The system of  claim 48 , further comprising transmitting signals to, from, or both to and from the at least one electrical contact portion via a generally continuous electrical signal path.  
     
     
         54 . A method for installing an intracranial signal transmission system, comprising: 
 forming an aperture in a patient's skull;    disposing proximate to the aperture an electrical contact portion carried by a support body, the support body having a shaft and a head depending from the shaft, the shaft having an external surface with a plurality of surface features;    inserting the shaft into the aperture; and    allowing the patient's bone tissue to grow into interengagement with the surface features.    
     
     
         55 . The method of  claim 54  wherein the surface features are recessed from the external surface of the shaft and wherein allowing the patient's bone tissue to grow includes allowing the patient's bone tissue to grow into the recesses.  
     
     
         56 . The method of  claim 54  wherein the surface features include pores and wherein allowing the patient's bone tissue to grow includes allowing the patient's bone tissue to grow into the pores.  
     
     
         57 . A method for installing an intracranial signal transmission system, comprising: 
 forming an aperture in a patient's skull;    disposing proximate to the aperture an electrical contact portion carried by a support body having a shaft and a head depending from the shaft    inserting the shaft into the aperture;    securing the support body to the patient's skull; and    receiving signals from a radio frequency transponder carried by at least one of the shaft and the head.    
     
     
         58 . The method of  claim 57 , further comprising controlling electrical stimulation signals transmitted to the electrical contact portion based on a signal received from the transponder.