Synchronization of wireless catheters

• US 9,241,632 B2
• Filed: 07/20/2011
• Issued: 01/26/2016
• Est. Priority Date: 07/20/2011
• Status: Active Grant

• Current Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Original Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Inventors: Kilim, Nahum, Govari, Assaf, Altmann, Andres Claudio, Ephrath, Yaron
• Primary Examiner(s): Porter, Jr., Allen
• Application Number:
  US13/186,626
• Publication Number:
  US 20130023746A1
• Time in Patent Office: 1,651 Days
• Field of Search: 600/509, 607/59, 607/60, 370/250, 370/503
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/0015 characterised by features of the telemetry system
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: H04J 3/06 Synchronising arrangements for television systems H04N5/04; bit-synchronisation H04L7/00
• CPC Class Codes: H04J 3/0635 Clock or time synchronisation in a network timer in protocols H04L69/28
• CPC Class Codes: H04J 3/0647 Synchronisation among TDM nodes
• CPC Class Codes: H04J 3/0658 Clock or time synchronisation among packet nodes
• CPC Class Codes: H04J 3/0661 using timestamps
• CPC Class Codes: H04J 3/0667 Bidirectional timestamps, e.g. NTP or PTP for compensation of clock drift and for compensation of propagation delays arrangements for monitoring round trip delays in packet switching networks H04L43/0864
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04L 1/00 Arrangements for detecting or preventing errors in the information received correcting synchronisation H04L7/00
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04Q 2209/845 where the measuring is synchronized between sensing devices
• CPC Class Codes: H04Q 9/04 Arrangements for synchronous operation

Abstract

A method includes disposing multiple medical probes to acquire physiological data concurrently from a living body. The data is sent from the multiple medical probes by transmitting over wireless channels respective sequences of data packets that are marked with respective packet numbers. A synchronization signal that is broadcast to the multiple probes is received in the probes. In response to receiving the synchronization signal, the packet numbers that are to be assigned in the probes to subsequent data packets in the respective sequences are reset.

Claims

1. A system, comprising:

multiple medical probes, each of which probes is configured to acquire physiological data from a living body with which the probe is in contact, to send the data from the probe by transmitting over a wireless channel a sequence of data packets that are marked with respective packet numbers, to receive a synchronization signal that is broadcast to the multiple probes, and, in response to receiving the synchronization signal, to reset the packet numbers that are assigned in the probe to subsequent data packets in the sequence, wherein the synchronization signal does not reset an internal clock of the probes; and

a central control unit, which is configured to transmit the synchronization signal, to receive multiple respective sequences of the data packets from the multiple probes, to time-synchronize the data transmitted in the data packets and to output the time-synchronized data for synchronizing the subsequent data packets.

2. The system according to claim 1, wherein each probe is configured to transmit a respective acknowledgement packet in response to receiving the synchronization signal at the probe, and wherein the central control unit is configured to receive respective acknowledgement packets transmitted by the probes and to time-synchronize the data based on the received acknowledgement packets.

3. The system according to claim 2, wherein each probe is configured to indicate in the respective acknowledgement packet a respective time offset at which the synchronization signal was received at the probe, relative to a data packet produced by the probe.

4. The system according to claim 3, wherein the central control unit is configured to time-synchronize the data based on multiple time offsets indicated in the acknowledgement packets transmitted by the probes.

5. The system according to claim 3, wherein the central control unit is configured to estimate, based on multiple time offsets indicated in the acknowledgement packets transmitted by the probes, a time period during which the data is not synchronized, and to discard the data belonging to the estimated time period.

6. The system according to claim 3, wherein each probe is configured to indicate in the respective acknowledgement packet a respective last packet number of a last data packet that was transmitted from the probe before reception of the synchronization signal, and wherein the central control unit is configured to determine a highest packet number of multiple last packet numbers indicated in the acknowledgement packets transmitted by the probes and to extract the time offset from the data packet having the highest number.

7. The system according to claim 2, wherein the central control unit is configured to present the time-synchronized data to an operator.

8. The system according to claim 1, wherein the central control unit is configured to evaluate a predefined criterion, and to transmit the synchronization signal upon meeting the criterion.

9. The system according to claim 8, wherein the central control unit is configured to evaluate the criterion by estimating a time difference between the multiple probes based on the received data packets, and comparing the time difference to a threshold.

10. The system according to claim 8, wherein the central control unit is configured to transmit the synchronization signal at periodic intervals.

11. The system according to claim 1, wherein the probes comprise intracardiac catheters, and wherein the sensors comprise electrodes that measure electrical signals in a heart.