Devices and methods for performing cryo therapy, cryo ablation or cryoplasty. A cryo therapy apparatus may comprise an elongate shaft, a cooling member disposed at the distal end of the shaft, and a pressure gauge coupled to the cooling member.
1. A cryo therapy device, comprising:
an elongate shaft having a proximal end and a distal end;
a cooling member disposed at the distal end, wherein the cooling member comprises an outer member and an inflatable inner member; and
a strain sensor attached to a surface of the inner member to provide an indication of the strain on the surface.
2. The cryo therapy device of claim 1 , wherein the surface is an inner surface of the inner member.
3. The cryo therapy device of claim 1 , wherein the surface is an outer surface of the inner member.
4. The cryo therapy device of claim 1 , wherein the strain sensor provides an output signal corresponding to a strain on the surface.
5. The cryo therapy device of claim 1 , wherein the strain sensor comprises a strain gauge.
6. The cryo therapy device of claim 1 , wherein the strain sensor comprises a fuse link.
7. The cryo therapy device of claim 1 , further comprising a relief cutting means for relieving the pressure in the inner member.
8. The cryo therapy device of claim 7 , wherein the relief cutting means is operable to relieve pressure in the inner member when the strain sensor detects that a strain on the surface of the inner member exceeds a predetermined threshold.
9. The cryo therapy device of claim 8 , wherein the relief cutting means comprises a radio-frequency energy source.
10. The cryo therapy device of claim 8 , further comprising a relief valve disposed within the inner member.
11. The cryo therapy device of claim 10 , wherein the relief cutting means comprises a laser energy source in optical communication with the relief valve by fiber optic cable.
12. The cryo therapy device of claim 10 , wherein the relief cutting means comprises an ultrasonic energy source in mechanical communication with the relief valve.
13. The cryo therapy device of claim 1 , further comprising a pressure release tube having a proximal end, a distal end, and a lumen extending therethrough.
14. The cryo therapy device of claim 13 , wherein the pressure release tube is in fluid communication with the inner member.
15. The cryo therapy device of claim 14 , wherein the pressure release tube further comprises a removable valve disposed at the proximal end thereof.
16. The cryo therapy device of claim 13 , wherein the pressure release tube further comprises a pressure-sensitive valve disposed at the distal end thereof.
17. The cryo therapy device of claim 13 , further comprising a fuse link coupled to the pressure release tube.
18. The cryo therapy device of claim 17 , wherein the fuse link is disposed over an opening within the pressure relief tube and wherein the fuse link is coupled to the strain sensor.
19. A method, comprising:
providing an elongate shaft having a proximal end and a distal end;
disposing a cooling member at the distal end, wherein the cooling member comprises an outer member and an inflatable inner member; and
attaching a strain sensor to a surface of the inner member to provide an indication of the strain on the surface.
20. The method of claim 19 , wherein the strain sensor comprises a strain gauge.