METHODS AND SYSTEMS FOR TREATING OCCLUDED BLOOD VESSELS AND OTHER BODY CANNULA
A method of treating an occluded blood vessel includes sensing the impedance at a plurality of locations around the circumference of the blood vessel at least two different frequencies to identify vascular occlusive material, and distinguish vascular occlusive material from the vessel wall.
1 . A method of treating an occluded blood vessel, the method comprising:
sensing the impedance at a plurality of locations around the circumference of the blood vessel at least two different frequencies to identify vascular occlusive material, and distinguish vascular occlusive material from the vessel wall.
2 . The method of claim 1 further comprising applying ablative energy to the identified vascular occlusive material.
3 . The method of claim 2 further comprising moving an electrode toward a location where vascular occlusive material has been identified, and applying ablative energy to the vascular occlusive material at the location.
4 . The method of claim 1 wherein sensing the impedance at least two frequencies is done simultaneously.
5 . The method of claim 1 wherein sensing the impedance at least two frequencies is done contemporaneously.
6 . The method of claim 1 wherein sensing the impedance at least two frequencies is done within 10 ms.
7 . The method of claim 1 wherein the impedance is sensed between two electrodes disposed in the blood vessel.
8 . The method of claim 1 wherein the impedance is sensed between an electrode in the blood vessel and an electrode outside of the blood vessel.
9 . The method of claim 1 wherein the two frequencies are sufficiently different to yield different impedance measurements for the living tissue of the vessel.
10 . The method of claim 9 wherein the two frequencies include about 10 kHz and 100 kHz.
11 . A method of treating an occluded blood vessel, the method comprising:
positioning a medical device in the blood vessel, the medical device having a plurality of electrodes around its circumference; and
sensing the impedance at a plurality of locations around the circumference of the blood vessel with the plurality of electrodes at least two different frequencies to identify vascular occlusive material, and distinguish vascular occlusive material from the vessel wall.
12 . The method of claim 11 further comprising applying ablative energy to the identified vascular occlusive material.
13 . The method of claim 11 further comprising using at least one of the electrodes on the medical device to apply ablative energy to the identified vascular occlusive material.
14 . The method of claim 11 wherein sensing the impedance at least two frequencies is done simultaneously.
15 . The method of claim 11 wherein sensing the impedance at least two frequencies is done contemporaneously.
16 . The method of claim 11 wherein sensing the impedance at least two frequencies is done within 10 ms.
17 . The method of claim 11 wherein the impedance is sensed between two electrodes disposed in the blood vessel.
18 . The method of claim 17 wherein the two electrodes are disposed on the same medical device.
19 . The method of claim 17 wherein the two electrodes are disposed on different medical devices.
20 . The method of claim 11 wherein the impedance is sensed between an electrode in the blood vessel and an electrode outside of the blood vessel.
21 . The method of claim 11 wherein the two frequencies are sufficiently different to yield different impedance measurements for the living tissue of the vessel.
22 . The method of claim 11 wherein the two frequencies include about 10 kHz and 100 kHz.
23 . A method of identifying vascular occlusive material in a vessel, comprising rotating and axially moving a electrode device through the vessel and measuring the impedance at points along the length of the device at least two frequencies, to distinguish between vascular occlusive material and vessel wall.
24 . The method of claim 23 further comprising making a three dimensional map of the location of vascular occlusive material based upon the impedance measurements.