Energy transfer amplification for intrabody devices

• US 8,386,021 B2
• Filed: 10/06/2009
• Issued: 02/26/2013
• Est. Priority Date: 07/29/2003
• Status: Active Grant

• Current Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Original Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Inventors: Govari, Assaf, Levin, Michael
• Primary Examiner(s): Chen, Tse
• Assistant Examiner(s): IP, JASON M
• Application Number:
  US12/574,374
• Publication Number:
  US 20100023092A1
• Time in Patent Office: 1,239 Days
• Field of Search: 600/407, 600/424, 600/430, 600/431, 600/433, 600/434, 600/435, 600/13, 600/14
• US Class Current: 600/424
• CPC Class Codes: A61B 2090/3975 active
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: A61B 5/6846 specially adapted to be brought in contact with an internal body part, i.e. invasive
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/4657 Measuring instruments used for implanting artificial joints for surgical instruments A61B90/06
• CPC Class Codes: A61F 2002/3067 for data transfer
• CPC Class Codes: A61F 2002/3429 with an integral peripheral collar or flange, e.g. oriented away from the shell centre line
• CPC Class Codes: A61F 2002/3611 Heads or epiphyseal parts of femur
• CPC Class Codes: A61F 2002/4658 for measuring dimensions, e.g. length
• CPC Class Codes: A61F 2002/4668 for measuring angles
• CPC Class Codes: A61F 2250/0002 for data transfer
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

Apparatus for driving current in a power circuit of a medical device inserted into a body of a subject includes a power transmitter, which is adapted to generate, in a vicinity of the body, an electromagnetic field having a predetermined frequency capable of inductively driving the current in the power circuit. A passive energy transfer amplifier, having a resonant response at the frequency of the electromagnetic field is placed in proximity to the medical device so as to enhance the current driven in the power circuit by the electromagnetic field.

Claims

1. Apparatus adapted to drive current in a wireless position sensor comprising a power circuit, a power coil, and a sensing coil, the wireless position sensor adapted to be inserted into a body of a subject to wirelessly transmit position signals indicative of a position of the wireless position sensor in the body of the subject, the apparatus comprising:

a power transmitter, which is adapted to generate, in a vicinity of the body, an RF electromagnetic field having a predetermined frequency capable of driving the current in the power circuit of the wireless position sensor, and dependent upon a spatial position and orientation of the sensing coil, cause currents to flow in the sensing coil, the power circuit converting the currents flowing in the sensing coil into position signals;

a passive energy transfer amplifier, having a resonant response at the frequency of the electromagnetic field and adapted to be implanted in the body and placed in proximity to the wireless position sensor so as to enhance inductive driving of the power coil of the wireless position sensor, by amplifying the RF electromagnetic field and causing a greater current flow in the power coil of the wireless position sensor so as to enhance the current driven in the power circuit by the electromagnetic field, the power coil of the wireless position sensor transmitting the position signals for determining six position and orientation coordinates of the wireless position sensor, wherein six position and orientation coordinates of the wireless position sensor comprise X, Y, Z directions and pitch, yaw, and roll orientations; and

a signal processing unit adapted to receive position signals from the power coil of the wireless position sensor and determining six position and orientation coordinates of the wireless position sensor.

2. The apparatus according to claim 1, wherein the passive energy transfer amplifier comprises a coil and a capacitance, which are coupled so as to define a resonant circuit having the resonant response at the frequency of the electromagnetic field.

3. A method for driving current in a wireless position sensor comprising a power circuit, a power coil, and a sensing coil, the wireless position sensor adapted to be inserted into a body of a subject to wirelessly transmit position signals indicative of a position of the wireless position sensor in the body of the subject, the method comprising:

generating, in a vicinity of the body, an RF electromagnetic field having a predetermined frequency capable of driving the current in the power circuit of the wireless position sensor and dependent upon a spatial position and orientation of the sensing coil, cause currents to flow in the sensing coil, the power circuit converting the currents flowing in the sensing coil into position signals;

placing a passive energy transfer amplifier, having a resonant response at the frequency of the electromagnetic field, in the body in proximity to the wireless position sensor so as to enhance inductive driving of the power coil of the wireless position sensor, by amplifying the RF electromagnetic field and causing a greater current flow in the power coil of the wireless position sensor so as to enhance the current driven in the power circuit by the RF electromagnetic field;

transmitting position signals from the power coil of the wireless position sensor for determining six position and orientation coordinates of the wireless position sensor; and

determining six position and orientation coordinates of the wireless position sensor based on the transmitted position signals from the power coil of the wireless position sensor, wherein six position and orientation coordinates of the wireless position sensor comprise X, Y, Z directions and pitch, yaw, and roll orientations.

4. The method according to claim 3, wherein the passive energy transfer amplifier comprises a coil and a capacitance, which are coupled so as to define a resonant circuit having the resonant response at the frequency of the electromagnetic field.