Glucose Monitor Calibration Algorithm Using Regression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current glucose monitoring systems face challenges in providing continuous, accurate, and comfortable glucose level data for diabetic patients, as traditional methods involve painful finger pricks and lack effective non-invasive solutions that offer continuous data beyond discrete points.
Innovation Solution
A method and apparatus for calibrating glucose monitor data by obtaining reference glucose values from a blood glucose meter, using regression techniques to calculate calibration characteristics, and applying these to glucose monitor data for continuous calibration, allowing for real-time and post-processing calibration of glucose levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional finger prick blood glucose testing is used, then accurate glucose measurement is obtained, but patient comfort and compliance deteriorate due to pain and discomfort
Solution Approach 1:
The patent replaces the mechanical finger prick lancet system with an implantable electrochemical sensor that continuously monitors glucose levels through a small incision in the abdominal wall. This substitutes the repeated mechanical trauma of finger pricks with a single implantable sensor that provides continuous data without pain.
Solution Approach 2:
The patent transitions from discrete point measurements via finger pricks to continuous glucose monitoring. The implantable sensor continuously measures glucose levels in interstitial fluid, providing uninterrupted data streams that eliminate the need for repeated painful testing while maintaining measurement accuracy.
2Measurement precision
If discrete point glucose measurements are obtained, then accurate reference values are provided, but continuous monitoring capability is lost
Solution Approach 1:
The implantable sensor continuously measures glucose levels in interstitial fluid from the time of implantation throughout the sensor's operational life (typically 7-14 days). This continuous action provides both accurate reference values and continuous monitoring capability, eliminating the trade-off between discrete accuracy and continuous data availability.
Solution Approach 2:
The patent uses interstitial fluid as an intermediary medium between blood glucose and the sensor. Glucose diffuses from the blood through the tissue into the sensor, allowing continuous measurement of glucose levels without direct blood contact, thus enabling both accuracy and continuity.
3Loss of time
If calibration is performed using single reference point, then calibration speed is improved, but calibration accuracy and reliability deteriorate
Solution Approach 1:
The system performs preliminary calibration using multiple reference measurements taken at different times during the sensor's operational period. These preliminary calibration points are stored and then used to calculate a final calibrated glucose value, ensuring both speed and reliability by preparing calibration data in advance.
Solution Approach 2:
The system uses feedback from multiple reference glucose measurements to iteratively improve the calibration. The measured reference values are compared with sensor readings, and the calibration factor is adjusted accordingly, creating a feedback loop that ensures both rapid and reliable calibration.
4Measurement precision
If multiple reference measurements are used for calibration, then calibration accuracy is improved, but calibration complexity and time consumption increase
Solution Approach 1:
The system performs self-calibration by automatically using the implantable sensor's own reference measurements to adjust its calibration factor. The sensor system itself generates the calibration data and performs the calculation, eliminating the need for external calibration equipment or complex manual procedures.
Solution Approach 2:
The patent merges the calibration function with the monitoring function into a single integrated system. The same sensor that continuously monitors glucose also uses its own reference measurements to perform calibration, combining multiple functions into one device and simplifying the overall process.
Data Source
Figure 1~2
Figure 3~7
Figure 8(A)~8(C)
AI summary
A method of calibrating glucose monitor data includes collecting the glucose monitor data over a period of time at predetermined intervals, obtaining reference glucose values from a reference source that temporally correspond with the glucose monitor data obtained at the predetermined intervals, calculating the calibration characteristics using the reference glucose values and corresponding glucose monitor data to regress the obtained glucose monitor data, and calibrating the obtained glucose monitor data using the calibration characteristics. In additional embodiments, calculation of the calibration characteristics includes linear regression and, in particular embodiments, least squares linear regression. Alternatively, calculation of the calibration characteristics includes non-linear regression. Data integrity may be verified and the data may be filtered.; Further, calibration techniques may be modified during a fast rate of change in the patient's blood glucose level to increase sensor accuracy.