Closed Loop Control System based on a Non-Invasive Continuous Sensor

• US 20150148774A1
• Filed: 11/22/2013
• Published: 05/28/2015
• Est. Priority Date: 11/22/2013
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Yao, Huanfen
• Granted Patent: US 9,452,260 B2
• Time in Patent Office: Days
• US Class Current: 604/504
• CPC Class Codes: A61B 2010/0067 Tear or lachrymal fluid
• CPC Class Codes: A61B 2560/0214 of power generation or supply
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 5/002 Monitoring the patient using a local or closed circuit, e.g. in a room or building A61B5/0017 takes precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/14507 specially adapted for measuring characteristics of body fluids other than blood devices for taking samples of body liquids A61B10/0045
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1477 non-invasive
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 5/6821 Eye
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3561 local, e.g. within room or hospital
• CPC Class Codes: A61M 2205/3576 with non implanted data transmission devices, e.g. using external transmitter or receiver
• CPC Class Codes: A61M 2205/3584 using modem, internet or bluetooth
• CPC Class Codes: A61M 2205/3592 using telemetric means, e.g. radio or optical transmission
• CPC Class Codes: A61M 2205/6054 Magnetic identification systems
• CPC Class Codes: A61M 2210/0612 Eyes
• CPC Class Codes: A61M 2230/005 Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/201 : Glucose concentration
• CPC Class Codes: A61M 5/142 : Pressure infusion, e.g. using pumps
• CPC Class Codes: A61M 5/14244 : adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/1723 : using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: G02C 7/04 : Contact lenses for the eyes disinfection or sterilisation of contact lenses A61L12/00

Abstract

Methods and systems for controlling analyte levels are described. An example method may include receiving a sensor measurement relating to an eye-mountable device. The method also may include determining an analyte concentration based on the one or more sensor measurements, and comparing the analyte concentration to a target analyte concentration. Based on the comparing, the method further may include providing instructions to a drug delivery device, where the instructions are configured to control a drug delivery rate by the drug delivery device.

Claims

1. A method comprising:

receiving one or more sensor measurements relating to an eye-mountable device, wherein the eye-mountable device comprises a polymeric material having a concave surface and a convex surface opposite the concave surface, and wherein the concave surface is configured to be removably mounted over a corneal surface and the convex surface is configured to be compatible with eyelid motion when the concave surface is so mounted;

determining a glucose concentration based on the one or more sensor measurements;

obtaining a target glucose concentration;

comparing the glucose concentration to the target glucose concentration; and

based on the comparing, providing instructions to an insulin delivery device, wherein the instructions are configured to control an insulin delivery rate by the insulin delivery device.

2. The method of claim 1, wherein the glucose concentration compared to the target glucose concentration is a blood glucose concentration, and wherein determining the glucose concentration based on the one or more sensor measurements comprises:

determining a tear-film glucose concentration based on the one or more sensor measurements; and

determining the blood glucose concentration based on the tear-film glucose concentration.

3. The method of claim 1, further comprising:

providing the glucose concentration to a display device configured to generate a display of variation of the glucose concentration over time.

4. The method of claim 1, further comprising:

establishing a rate of change of glucose concentration based on the one or more sensor measurements, wherein the instructions to the insulin delivery device are further based on the established rate of change of glucose concentration.

5. The method of claim 1, further comprising:

establishing a range of glucose concentration about the target glucose concentration based on patient-specific information, wherein providing the instructions comprises;

providing instructions configured to maintain a predetermined insulin delivery rate by the insulin delivery device, when the glucose concentration is within the range; and

providing instructions configured to change the insulin delivery rate by the insulin delivery device, when the glucose concentration is outside of the range.

6. The method of claim 1, wherein the eye-mountable device is in communication with a reader, and wherein receiving the one or more sensor measurements comprises receiving the one or more sensor measurements by way of the reader.

7. The method of claim 6, wherein the reader is configured to wirelessly communicate with the eye-mountable device so as to request and receive the one or more sensor measurements.

8. The method of claim 7, wherein the reader is configured to wirelessly power the eye-mountable device.

9. The method of claim 6, wherein the reader is part of a head-mountable device (HMD).

10. The method of claim 1, wherein the one or more sensor measurements relate to a tear-film contacting the eye-mountable device, and wherein the one or more sensor measurements are obtained by a glucose sensor in the eye-mountable device.

11. A system comprising:

an eye-mountable device including a polymeric material having a concave surface and a convex surface opposite the concave surface, wherein the concave surface is configured to be removably mounted over a corneal surface and the convex surface is configured to be compatible with eyelid motion when the concave surface is so mounted;

an electrochemical sensor mounted in the eye-mountable device and configured to provide one or more sensor measurements;

a reader including one or more antennas configured to;

(i) transmit radio frequency (RF) radiation to power the eye-mountable device and the electrochemical sensor, and (ii) receive indications of the one or more sensor measurements; and

a controller in communication with the reader, wherein the controller is configured to;

(i) receive information related to the one or more sensor measurements from the reader;

(ii) determine a glucose concentration based on the information;

(iii) obtain a target glucose concentration;

(iv) compare the glucose concentration to the target glucose concentration; and

(v) based on the comparing, provide instructions to an insulin delivery device to control an insulin delivery rate to a blood stream by the insulin delivery device.

12. The system of claim 11, wherein the controller is integrated into:

(i) the reader, (ii) the insulin delivery device, or (iii) a remote device in communication with the reader and the insulin delivery device.

13. The system of claim 11, wherein the eye-mountable device further includes a reagent that selectively reacts with an analyte in a tear-film contacting the eye-mountable device, and wherein the reagent is localized proximate the electrochemical sensor.

14. The system of claim 11, wherein the reader is configured to transmit the RF radiation to power the eye-mountable device and the electrochemical sensor at least a predetermined period of time before receiving the indications of the one or more sensor measurements.

15. The system of claim 11, wherein the polymeric material includes a channel configured to expose the electrochemical sensor to a tear-film contacting the polymeric material of the eye-mountable device.

16. The system of claim 11, wherein the controller is further configured to establish a rate of change of glucose concentration based on the information related to the one or more sensor measurements, wherein the instructions to the insulin delivery device are further based on the established rate of change of glucose concentration.

17. A non-transitory computer readable medium having stored thereon instructions that, when executed by a computing device, cause the computing device to perform functions comprising:

receiving information related to one or more sensor measurements indicative of a concentration of an analyte, wherein the one or more sensor measurements are obtained by a sensor in an eye-mountable device, wherein the eye-mountable device comprises a transparent polymeric material having a concave surface and a convex surface opposite the concave surface, wherein the concave surface is configured to be removably mounted over a corneal surface and the convex surface is configured to be compatible with eyelid motion when the concave surface is so mounted;

determining the concentration of the analyte based on the information;

obtaining a target concentration for the analyte;

comparing the concentration of the analyte to the target concentration for the analyte; and

based on the comparing, providing instructions to a drug delivery device, wherein the instructions are configured to control a drug delivery rate by the drug delivery device.

18. The non-transitory computer readable medium of claim 17, wherein the functions further comprise:

establishing a rate of change of concentration of the analyte based on the one or more sensor measurements, wherein the instructions to the drug delivery device are further based on the established rate of change of concentration of the analyte.

19. The non-transitory computer readable medium of claim 17, wherein the functions further comprise:

establishing a range of concentration for the analyte about the target concentration based on patient-specific information, wherein providing the instructions comprises;

providing instructions configured to maintain a predetermined drug delivery rate by the drug delivery device, when the concentration of the analyte is within the range; and

providing instructions configured to change the drug delivery rate by the drug delivery device, when the concentration of the analyte is outside of the range.

20. The non-transitory computer readable medium of claim 17, wherein the eye-mountable device is in communication with a reader that is part of a head-mountable device, wherein the reader is configured to wirelessly communicate with and wirelessly power the eye-mountable device, and wherein the function of receiving the information related to the one or more sensor measurements comprises receiving the information from the reader.