Synchronization and calibration of clocks for a medical device and calibrated clock

• US 7,624,293 B2
• Filed: 02/15/2006
• Issued: 11/24/2009
• Est. Priority Date: 10/15/2002
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Bhavaraju, Naresh C., Peters, Thomas E., Werder, Jonathan C., Frei, Mark G., Osorio, Ivan
• Primary Examiner(s): Lee; Thomas
• Assistant Examiner(s): Rahman; Fahmida
• Application Number:
  US11/355,489
• Publication Number:
  US 20060155495A1
• Time in Patent Office: 1,378 Days
• Field of Search: 713/400, 713/401, 713/500, 713/600
• US Class Current: 713/400
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/374 Detecting the frequency distribution of signals, e.g. detecting delta, theta, alpha, beta or gamma waves
• CPC Class Codes: A61B 5/4094 Diagnosing or monitoring seizure diseases, e.g. epilepsy
• CPC Class Codes: A61N 1/025 Digital circuitry features of electrotherapy devices, e.g. memory, clocks, processors
• CPC Class Codes: A61N 1/36025 for treating a mental or cerebral condition
• CPC Class Codes: A61N 1/36082 Cognitive or psychiatric applications, e.g. dementia or Alzheimer's disease
• CPC Class Codes: A61N 1/37 Monitoring; Protecting
• CPC Class Codes: A61N 1/372 Arrangements in connection with the implantation of stimulators
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: G04G 7/00 Synchronisation radio-controlled time-pieces G04R
• CPC Class Codes: G16H 40/40 for the management of medical equipment or devices, e.g. scheduling maintenance or upgrades
• CPC Class Codes: G16H 40/63 for local operation

Abstract

Apparatus and method support the synchronization and calibration of a plurality of clocks in a medical device system that may provide treatment to a patient with a nervous system disorder. The plurality of clocks, which may be located at different components of the medical device system, comprises a first clock and a second clock. The second clock may be synchronized to a first clock by disabling a run mode operation and setting the second clock to a selected time. When a reference time of the first clock approximately equals the selected time, the second clock enables the run mode operation. Additionally, a drift time that is indicative of a time difference between the first clock and the second clock is determined. If the drift time is greater than a predetermined amount, an indication to resynchronize the first and second clocks is provided.

Claims

1. A method for synchronizing a plurality of clocks, the plurality of clocks comprising a first slave clock and a master clock, the method comprising:

(a) determining whether to synchronize the first slave clock to the master clock, wherein at least one of the first slave clock or the master clock is associated with a medical device system;

(b) in response to (a), disabling a run mode operation of the medical device system;

(c) determining a delay time between a first time and a second time, wherein the first time includes the time for initiating the synchronization of the first slave clock and the master clock and the second time includes the time for receiving an indication to synchronize;

(d) in response to (a), sending a reference time by the master clock;

(e) setting the first slave clock to the reference time; and

(f) enabling the run mode operation of the medical device system.

2. The method of claim 1, wherein the master clock and the first slave clock communicate through a communications channel selected from the group consisting of a wireless channel, an Intranet connection, and an Internet connection.

3. The method of claim 1, wherein the plurality of clocks further comprises a second slave clock, and step (e) further comprises

setting the second slave clock to the reference time.

4. The method of claim 1, wherein one of the first and the second slave clocks is configured to be implanted in a patient.

5. The method of claim 1, wherein the determining in (a) comprises:

(i) receiving a current time of the first slave clock;

(ii) determining a difference between the current time and a master clock time; and

(iii) if the difference is greater than a predetermined amount, determining to synchronize the first slave clock with the master clock.

6. The method of claim 1, wherein the slave clock is configured to be implanted in a patient.

7. A method for synchronizing a plurality of clocks, the plurality of clocks comprising a first slave clock and a master clock, the method comprising:

(a) comparing a first current time of the first slave clock with a second current time of a master clock, wherein the first slave clock controls a multi-modal medical device system that provides treatment therapy to a patient with a medical condition;

(b) if the difference between the first and second current time is greater than a preset limit, determining to synchronize the first slave clock with the master clock;

(c) in response to (b), disabling a run mode operation of the medical device system;

(d) determining a delay time between a first time and a second time, wherein the first time includes the time for initiating the synchronization of the first slave clock and the master clock and the second time includes the time for receiving an indication to synchronize;

(e) in response to (b), providing a reference time from the master clock; and

(f) setting the first slave clock to the reference time; and

(g) enabling the run mode operation of the medical device system.

8. The method of claim 7, wherein the plurality of clocks further comprises a second slave clock, and step (f) further comprises

setting the second slave clock to the reference time.

9. The method of claim 8, wherein one of the first and second slave clocks is configured to be implanted within a patient.

10. The method of claim 7, wherein the providing in (e) is done over a communication channel selected from the group consisting of a wireless channel, a local area network, a wide area network, and an Internet connection.

11. The method of claim 7, wherein providing in (e) comprises:

(i) receiving a time signal from a clock reference; and

(ii) transmitting the time signal to the first slave clock.

12. The method of claim 11, wherein the clock reference is an atomic clock.

13. The method of claim 7, wherein the first slave clock is configured to be implanted within a patient.