Method for measuring ventricular pressure using a pressure sensing valve
A pressure sensing catheter having a pressure sensor and an antenna that is coupled to the pressure sensor, e.g., by a connector, are provided. The pressure sensor can be adapted to measure a pressure surrounding the catheter, and the antenna can be adapted to telemetrically communicate the measured pressure to an external device. In an exemplary embodiment, the antenna, pressure sensor, and/or connector are hermetically sealed, e.g., by the catheter and/or a coating, to prevent the antenna, pressure sensor, and connector from coming into contact with fluid, thereby allowing the catheter to be permanently implanted or otherwise used for long term use. Exemplary methods for manufacturing and using pressure sensing catheters are also provided.
1. A method for measuring ventricular pressure, comprising:
positioning a distal end of a ventricular catheter within a patient's ventricle;
coupling a proximal end of the ventricular catheter to a valve inlet formed on an implantable valve having a valve assembly and a pressure sensor disposed therein, and coupling a valve outlet formed on the valve to a drainage catheter such that fluid flows from the ventricle through the implantable valve to the drainage catheter, wherein a rate of fluid flowing through the valve is controlled by the valve assembly disposed within the implantable valve; and
obtaining a pressure measurement of the fluid flowing through the valve using the pressure sensor disposed within the valve, wherein the pressure sensor is located upstream of the valve assembly within the valve and thus the pressure measurement is made prior to the fluid flowing into the valve assembly.
2. The method of claim 1 , further comprising obtaining the pressure measurement telemetrically by positioning a reading device in proximity to the valve.
3. The method of claim 2 , wherein the pressure sensor is formed on a microchip that is coupled to an antenna that communicates the pressure measurement to the reading device.
4. The method of claim 1 , wherein the pressure sensor is in-line with the valve assembly.
5. The method of claim 1 , wherein the pressure sensor is disposed within a domed portion of the valve, the domed portion defining a reservoir therein, and wherein the pressure sensor obtains a pressure measurement of the pressure flowing through the reservoir in the domed portion.
6. The method of claim 5 , further comprising inserting a needle through the domed portion of the valve, wherein a needle guard protects the pressure sensor from coming into contact with the needle when the needle is inserted into the domed portion.
7. The method of claim 5 , further comprising depressing the domed portion of the valve to pump fluid through the reservoir.
8. The method of claim 1 , further comprising suturing at least one flange on the implantable valve to tissue to secure the implantable valve to tissue.
9. A method for measuring ventricular pressure, comprising:
implanting an implantable valve beneath a patient's scalp, the implantable valve having a pressure sensor assembly disposed therein for sensing pressure of a flow of fluid passing therethrough, and a valve assembly disposed therein for regulating the flow of fluid through the implantable valve, the pressure sensor assembly being distal of the valve assembly;
positioning a distal end of a ventricular catheter coupled to an outlet of the valve in a patient's ventricle;
coupling a valve outlet formed on the implantable valve to a drainage catheter such that fluid flows from the ventricle, through the pressure sensor assembly of the implantable valve, through the valve assembly of the implantable valve, and to the drainage catheter; and
positioning an external device adjacent to the patient's scalp to telemetrically communicate with an antenna disposed within the implantable valve and thereby obtain a reading of a pressure of fluid flowing through the implantable valve and measured by a pressure sensor disposed within the pressure sensor assembly and coupled to the antenna.
10. The method of claim 9 , further comprising depressing a domed portion of the implantable valve to pump fluid therethrough, the pressure sensor being disposed within a reservoir defined by the domed portion.