Device, system and methods for measurement of pressures in the urinary tract
A catheter for measuring pressure in the urinary tract of a patient includes a catheter body having a proximal and distal end. A plurality of lumens is formed in the catheter body, and an adaptor is coupled to the proximal end of the catheter body. The adaptor includes a port for each lumen. A first pressure sensor, typically including a balloon, is fluidically coupled to a first lumen and is configured and positioned to measure pressure in a urethra of the patient. A second pressure sensor, also typically including a balloon, is fluidically coupled to a second lumen and is configured and positioned on the catheter body to measure pressure in a bladder of the patient. An expandable retention member, which may be coupled to a third lumen, is positioned on the catheter body between the first and second expandable pressure sensors so that the catheter body may be retained at a selected location in the urinary tract to properly position the fluid pressure sensors in the bladder and urethra, respectively.
1. A method for measuring pressure at multiple locations in the urinary tract of a patient to facilitate a treatment for urinary incontinence, the method comprising:
advancing a catheter having a first and second pressure sensor into the urinary tract of a patient so as position the first pressure sensor at a first location in a urethra of the patient and the second pressure sensor at a second location in a bladder of the patient, the catheter including a plurality of lumens including at least a first lumen and a second lumen, the first pressure sensor fluidically coupled to the first lumen and the second pressure sensor fluidically coupled to the second lumen, wherein the plurality of lumens are configured so as to minimize an effect of a pressure change in one lumen of the plurality of lumens on a pressure in another lumen of the plurality of lumens;
expanding an expandable retention member so as to retain the first pressure sensor at the first location and the second pressure sensor at the second location during exertion of a physiological force on the catheter; and
measuring pressures at the first location and the second location in response to an external stimulus.
2. The method of claim 1 , wherein the pressures at the first and second location are measured substantially simultaneously.
3. The method of claim 1 , wherein the pressures at the first and second location are measured sequentially.
4. The method of claim 1 , wherein the external stimulus comprises an electrical signal.
5. The method of claim 4 , wherein the electrical signal comprise a neuromodulation signal generated by an electrode electrically coupled to a nerve innervating the bladder.
6. The method of claim 1 , wherein the external stimulus comprises adding fluid to the bladder from outside the body.
7. The method of claim 1 , wherein the physiological force corresponds to a hydrostatic pressure from fluid in the patient's bladder.
8. The method of claim 1 , wherein the physiological force corresponds to a force resulting from a contraction of at least one of the patient's bladder or urethral sphincter.
9. The method of claim 1 , wherein the at least one of the first or second pressure sensors comprises an expandable member, the method further comprising expanding at least of the first or second pressure sensors.
10. The method of claim 1 , wherein the catheter is configured such that measurement of the pressure at either of the locations is not substantially affected by a position of a pressure sensor at the other location.
11. The method of claim 10 , wherein the catheter includes a plurality of lumens including at least a first a second lumen, the first pressure sensor fluidically coupled to the first lumen and the second pressure sensor fluidically coupled to the second lumen.
12. The method of claim 11 , wherein the plurality of lumens are so as to minimize an effect of a pressure change in one lumen of the plurality of lumens on a pressure in another lumen of the plurality.
13. The method of claim 1 , wherein each lumen of the plurality of lumens has sufficient stiffness or hoop strength such that a pressure change in one lumen of the plurality causes a 5% or less pressure change in another lumen of the plurality of lumens.
14. The method of claim 1 , wherein each lumen of the plurality of lumens has sufficient stiffness or hoop strength such that a pressure change in one lumen of the plurality causes a 2% or less pressure change in another lumen of the plurality.
15. The method of claim 1 , wherein a radial rigidity of each lumen of the plurality of lumens is in a range of about 20 to 100 N/mm.
16. The method of claim 1 , wherein the radial rigidity of each lumen of the plurality of lumens is in a range of about 50 to 100 N/mm.