VAGAL NERVE STIMULATION TO REDUCE INFLAMMATION ASSOCIATED WITH AN ANEURYSM
Devices, systems and methods are disclosed for reducing inflammation associated with an aneurysm in a patient. The methods comprise transmitting impulses of energy non-invasively to selected nerve fibers, particularly those in the vagus nerve. Vagus nerve stimulation is used to modulate the release of neurotransmitters in the brain and to reduce inflammation that may lead to the formation, growth, rupture or hemorrhage of an aneurysm.
1 . A device for reducing inflammation associated with an aneurysm in a patient, comprising:
a housing having a contact surface for contacting an outer skin surface of a neck of the patient;
an energy source within the housing and coupled to the contact surface, wherein the energy source generates at least one electric impulse and transmits the at least one electrical impulse transcutaneously and non-invasively from the contact surface through the outer skin surface of the patient to a selected nerve fiber in the patient, wherein the at least one electrical impulse comprises bursts of pulses with each burst having a frequency of about 1 to about 100 bursts per second and each pulse has a duration of about 100 to about 1000 microseconds in duration; and
wherein the at least one electrical impulse is sufficient to modify the nerve fiber, such that inflammation associated with the aneurysm is reduced.
2 . The device of claim 1 , wherein the electrical impulse is sufficient to at least inhibit rupture of the aneurysm.
3 . The device of claim 1 , wherein the electrical impulse is sufficient to at least inhibit hemorrhage of the aneurysm.
4 . The device of claim 1 , wherein the electrical impulse is sufficient to at least inhibit formation or growth of the aneurysm.
5 . The device of claim 1 , wherein the aneurysm is located in a brain of the patient.
6 . The device of claim 1 , wherein the energy source comprises a signal generator and one or more electrodes coupled to the signal generator within the housing.
7 . The device of claim 1 , further comprising a conducting medium within the housing between the electrodes and the contact surface.
8 . The device of claim 1 , wherein the electrical impulse is sufficient to stimulate a vagus nerve of the patient.
9 . The device of claim 1 , wherein the electrical impulse is sufficient to generate an electric field at the selected nerve fiber, wherein the electric field is from about 10 V/m to about 600 V/m.
10 . The device of claim 9 , wherein the electric field is less than about 100 V/m.
11 . The device of claim 1 , wherein the selected nerve is associated with a vagus nerve of the patient.
12 . The device of claim 1 , wherein each of the pulses has a duration from about 200 microseconds to about 400 microseconds.
13 . The device of claim 1 , wherein the electrical impulse has a frequency from about 1,000 Hz to about 10,000 Hz and a duty cycle from about 1% to about 10%.
14 . The device of claim 1 , wherein the electrode is spaced from the contact surface by a distance of about 0.25 to about 4 times an outer dimension of the contact surface.
15 . A method of reducing inflammation associated with an aneurysm in a patient, the method comprising:
contacting a contact surface of a housing against an outer skin surface of a neck of the patient, wherein the housing includes a power source coupled to the contact surface;
generating, with the power source, at least one or more electrical impulse; and
transmitting the at least one electrical impulse transcutaneously and non-invasively from the contact surface through the outer skin surface of the neck to a selected nerve fiber in the patient during the contacting, wherein the at least one electrical impulse comprises bursts of pulses with each burst having a frequency of about 1 to about 100 bursts per second and each pulse having a duration of about 100 to about 1000 microseconds, and wherein the at least one electrical impulse is sufficient to modify the nerve fiber, such that inflammation associated with the aneurysm is reduced.
16 . The method of claim 15 , wherein the transmitting comprises transmitting the at least one electrical impulse through a conducting medium stored within the housing.
17 . The method of claim 15 , further comprising:
generating an electric field at or near the housing; and
shaping the electric field such that the electric field is sufficient to modulate a nerve fiber at a target region, and wherein the electric field is insufficient to substantially modulate at least one of a nerve or a muscle between the outer skin surface and the target region.
18 . The method of claim 15 , wherein the power source comprises a signal generator, and one or more electrodes coupled to the signal generator.
19 . The method of claim 17 wherein the electric field at the nerve fiber at the target region is from about 10 V/m to about 600 V/m.
20 . The method of claim 19 wherein the electric field is less than about 100 V/m.
21 . The method of claim 1 , wherein the at least one electrical impulse generated by the power source comprises a sufficient amplitude to pass through the outer skin surface to the nerve fiber at the target region that is at least from about 0.5 cm to about 2 cm below the outer skin surface.
22 . The method of claim 15 , wherein the selected nerve fiber is associated with a vagus nerve of the patient.
23 . The method of claim 15 , wherein each of the bursts contains from about 2 pulses to about 20 pulses.
24 . The method of claim 15 wherein the pulses are full sinusoidal waves.
25 . The method of claim 15 , wherein the duration of each of the pulses is about 200 to about 400 microseconds.
26 . The method of claim 15 , wherein the at least one electrical impulse generates an electric field at a vagus nerve above a threshold for generating an action potential within at least one of an A fiber or a B fiber of the vagus nerve and below a threshold for generating an action potential within a C fiber of the vagus nerve.
27 . The method of claim 15 , wherein the at least one electrical impulse generates an electric field at a vagus nerve above a threshold for generating an action potential within a fiber of the vagus nerve responsible for activating a neural pathway causing a release of an inhibitory neurotransmitter within a brain of the patient.
28 . The method of claim 15 , wherein the electrical impulse is sufficient to at least inhibit rupture of the aneurysm.
29 . The method of claim 15 , wherein the electrical impulse is sufficient to at least inhibit hemorrhage of the aneurysm.
30 . The method of claim 15 , wherein the electrical impulse is sufficient to at least inhibit formation or growth of the aneurysm.
31 . The method of claim 15 , wherein the aneurysm is located in a brain of the patient.
32 . A method of reducing inflammation in a patient with an aneurysm, the method comprising:
contacting a contact surface of a housing against an outer skin surface of a neck of the patient, wherein the housing includes a power source coupled to the contact surface;
generating, with the power source, at least one or more electrical impulse; and
transmitting the at least one electrical impulse transcutaneously and non-invasively from the contact surface through the outer skin surface of the neck to a selected nerve fiber in the patient during the contacting, wherein the at least one electrical impulse comprises bursts of pulses with each burst having a frequency of about 1 to about 100 bursts per second and each pulse having a duration of about 100 to about 1000 microseconds, and wherein the at least one electrical impulse is sufficient to modify the nerve fiber, such that inflammation is reduced in the patient.