MEDICAL DEVICE AND METHOD OF USE
Systems and methods for treating tissue with cryogenic media and/or high pressure jet media for cutting either sequentially or contemporaneously and removing tissue from a site in a patient body.
1 . A method of cutting and removing a target tissue, comprising:
introducing a working end of a probe into an interstitial site in a patient body;
activating a pressure source to provide a flow of a cryogenic media through the probe and jetting the cryogenic media from the working end at an operating parameter configured to mechanically remove tissue;
contemporaneously moving the working end; and
activating a negative pressure source coupled to a flow channel in the probe to extract the removed tissue and cryogenic media from the site.
2 . The method of claim 1 wherein moving the working end includes at least one of rotating, translating axially, reciprocating, oscillating and vibrating.
3 . The method of claim 2 wherein moving the working end in provided by a motor drive.
4 . The method of claim 1 further comprising sensing fluid pressure at the site and modulating an operating parameter of the flow in response to sensed fluid pressure in the site.
5 . The method of claim 1 wherein the cryogenic media includes a particulate material selected from the group of ice, biocompatible materials and bioresorbable materials.
6 . The method of claim 1 , further comprising pre-treating the interstitial site to cause a thermal change in tissue prior to activating the pressure source.
7 . The method of claims 4 further comprising monitoring a fluid pressure at the interstitial site using a pressure sensor in communication with a static fluid column extending to the interstitial site.
8 . The method of claim 7 wherein the static fluid column extends through an independent channel in the probe.
9 . The method of claims 4 further including de-activating the pressure source if the sensed pressure drops below a predetermined level.
10 . The method of claims 4 further including de-activating the pressure source if the sensed pressure drops below a predetermined level for a selected time interval.
11 . The method of claims 4 wherein the fluid pressure is monitored by a pressure sensor positioned proximate to the site.
12 . The method of claim 11 wherein the pressure sensor is carried by the probe.
13 . The method of claim 11 wherein the pressure sensor is carried by a member insertable through a channel in the probe.
14 . The method of claim 8 wherein the independent channel has a diameter of at least 0.5 mm.
15 . The method of claim 1 wherein the probe is operated to cut tissue at a rate of at least 5 grams per minute.
16 . The method of claims 1 wherein the probe extracts cut tissue through an extraction channel in the probe.
17 . The method of claim 2 wherein the working end is rotated at a rate of between 10 rpm and 1,000 rpm.
18 . The method of claims 1 wherein the cryogenic media is jetted from the working end through at least one jetting orifice.
19 . The method of claims 1 wherein the introducing step includes advancing the working end over a guide member to the site.