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

• US 7,321,837 B2
• Filed: 02/15/2006
• Issued: 01/22/2008
• Est. Priority Date: 10/15/2002
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Werder, Jonathan C., Frei, Mark G., Osorio, Ivan, Bhavaraju, Naresh C., Peters, Thomas E.
• Primary Examiner(s): Bui; Bryan
• Assistant Examiner(s): LE, JOHN H
• Application Number:
  US11/355,784
• Publication Number:
  US 20060161384A1
• Time in Patent Office: 706 Days
• Field of Search: 702176-178, 702/89, 600/439, 600/544, 600/545, 600/610, 607/27, 607/30, 607/32, 607/45, 607/60, 607/62, 607/116, 708/322, 381/56, 128/419
• US Class Current: 702/89
• 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 calibrating a plurality of clocks wherein at least one of the clocks is associated with a medical device system, the plurality of clocks comprising a first clock and a second clock, the method comprising:

(a) reading a first current time from the second clock;

(b) obtaining a reference time;

(c) subtracting the current time from a reference time in order to determine a first drift time;

(d) storing the first drift time into a memory;

(e) notifying a user to calibrate the first and second clocks;

(f) receiving a selected time, the selected time being different than the reference time;

(g) receiving an indication that the selected time approximately equals the reference time;

(h) obtaining a second current time from the second clock;

(i) subtracting the second current time from the selected time in order to determine a second drift time; and

(j) storing the second drift time into a memory.

2. The method of claim 1, wherein one of the first and second clocks is implanted within a patient.

3. The method of claim 1, wherein the reference time is obtained from an implanted device.

4. An apparatus for calibrating a plurality of clocks in a medical device system, the medical device system providing treatment to a patient with a nervous system disorder, the plurality of clocks comprising a first clock and a second clock, the apparatus comprising:

a user interface;

a communications interface that is coupled to the second clock;

a memory; and

a processor that is connected to the user interface in order to receive an instruction from a user, that is connected to the memory, and that instructs the second clock through the communications interface, the processor configured to perform the steps of;

(a) receiving a current time from the second clock;

(b) subtracting the current time from a reference time in order to determine a time difference;

(c) if the time difference is greater than a predetermined amount, resynchronizing the first and second clocks;

(d) notifying a user to calibrate the first and second clocks;

(e) receiving a selected time, the selected time being greater than the reference time;

(f) receiving an indication that the selected time approximately equals the reference time;

(g) obtaining the current time from the second clock;

(h) subtracting the current time from the selected time in order to determine a drift time; and

(i) storing the drift time into a memory.

5. The apparatus of claim 4, wherein the processor is configured to perform the further step of:

(j) if the drift time is greater than the predetermined amount, resynchronizing the first and second clocks.