IMPLANTABLE SYSTEM FOR FLOW MEASUREMENT INCLUDING CHARGE AMPLIFIER
First Claim
1. A flow measurement system comprising:
- a lead adapted for implantation within a patient;
at least one flow measurement means, mounted on the lead, for detecting a flow parameter of ionic media at a detecting position in a selected detecting area when the lead is inserted into the patient;
a capsule, positioned on the lead proximate to the flow measurement means, the flow measurement means comprising at least first and second electrodes, the capsule positioned on the lead proximate to at least the first electrode;
electrical circuitry, housed within the capsule and operatively connected to the first electrode, for receiving and processing flow signals from the flow measurement means; and
a plurality of electrical conductors contained in said lead, at least one conductor having a distal end operatively connected to the electrical circuitry and having a proximal end operatively connected to a medical device.
1 Assignment
0 Petitions
Accused Products
Abstract
An implantable medical device lead having a flow measurement sensor mounted thereon is provided with a capsule mounted proximate to the sensor. The capsule is used to house electrical circuitry corresponding to the sensor in order to prevent impedance on conductors of the lead, which gradually decreases over chronic periods, from directly affecting signal transmission between the sensor and the electrical circuitry. The electrical circuitry includes a charge amplifier used for processing signals from the sensor. In some cases, the amplifier can be initially calibrated and periodically tuned so as to have consistent functioning with the sensor over chronic periods.
-
Citations
20 Claims
-
1. A flow measurement system comprising:
-
a lead adapted for implantation within a patient; at least one flow measurement means, mounted on the lead, for detecting a flow parameter of ionic media at a detecting position in a selected detecting area when the lead is inserted into the patient; a capsule, positioned on the lead proximate to the flow measurement means, the flow measurement means comprising at least first and second electrodes, the capsule positioned on the lead proximate to at least the first electrode; electrical circuitry, housed within the capsule and operatively connected to the first electrode, for receiving and processing flow signals from the flow measurement means; and a plurality of electrical conductors contained in said lead, at least one conductor having a distal end operatively connected to the electrical circuitry and having a proximal end operatively connected to a medical device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. A medical device having flow measurement system capable of being dynamically adjusted following implantation within a patient comprising:
-
a lead adapted for implantation within a patient; at least one flow measurement means, mounted on the lead, for detecting a flow parameter of ionic media at a detecting position in a selected detecting area when the lead is inserted into the patient; a capsule positioned on the lead proximate to the flow measurement means; electrical circuitry housed within the capsule and operatively connected to the flow measurement means, the electrical circuitry adapted for receiving and processing flow signals from the flow measurement means, the electrical circuitry comprising at least one charge amplifier comprising one or more pluralities of electrical components, each of the pluralities connected to the charge amplifier via switches; a medical device comprising a control circuit operatively connected to the charge amplifier, the control circuit adapted to periodically determine source capacitance of the charge amplifier and adapted to trigger one or more of the switches to adjust one or more electrical characteristics of the amplifier to correspond with the determined source capacitance; and a plurality of electrical conductors contained in said lead, at least one conductor having a distal end operatively connected to the one or more of the switches and having a proximal end operatively connected to the control circuit, and at least another conductor having a distal end operatively connected to an output of the amplifier and having a proximal end operatively connected to the control circuit. - View Dependent Claims (15, 16, 17)
-
-
18. A method of calibrating and subsequent tuning a charge amplifier in an implantable medical device having flow measurement capability comprising the steps of:
-
providing a medical device having an implantable lead including at least one flow measurement means and capsule positioned thereon, the means adapted for detecting a flow parameter of ionic media at a detecting position in a selected detecting area when said lead is inserted into a patient, the capsule housing electrical circuitry that is operatively connected to the flow measurement means, the electrical circuitry at least comprising a charge amplifier; implanting the lead within the patient; determining a baseline capacitance of the flow measurement sensor following implantation of the lead; calibrating the charge amplifier by adjusting values of electrical components of the charge amplifier to correspond with the baseline capacitance; determining source capacitance of the charge amplifier following use of the medical device within the patient for a period of time; and tuning the charge amplifier if the source capacitance differs from the baseline capacitance by adjusting the values of the electrical components of the charge amplifier to correspond with the source capacitance. - View Dependent Claims (19, 20)
-
Specification