# How Devices Precisely Track Glucose Across Body Compartments > This patent describes a method for accurately estimating a person's blood glucose by accounting for the natural time delay in how glucose moves between different body fluids, like blood and the fluid around cells, to better control insulin pumps. - **Patent:** US 9854998 - **Original title:** Method and/or system for multicompartment analyte monitoring - **Owner:** Medtronic Minimed - **Granted:** 2018 - **Status:** Active - **Times cited:** 1 - **Field:** biotech, medical_devices, software, consumer_electronics ## What it does This patent describes a method and system for more accurately monitoring an analyte, such as glucose (Claim 3), in a person's body. It uses a sensor (Claim 7) to measure the analyte in a 'second physiological compartment,' like interstitial fluid (Claim 3). A controller or processor (Claim 1, 7) then estimates the time delay, or 'latency,' for the analyte to move between this second compartment and a 'first physiological compartment,' such as blood plasma (Claim 3). This estimation relies on at least one blood glucose reference sample (Claim 1, 7). The system then 'compensates' for this latency when calculating the analyte's concentration in the first compartment. This compensation involves accumulating differences between sensor readings and an offset, and combining this with a term that includes the estimated latency (Claim 1). Based on this more accurate estimate, the controller generates commands for infusion pumps (Claim 1, 7), such as an insulin pump, to adjust treatment. For example, a continuous glucose monitor (CGM) measures glucose in interstitial fluid, and this patent helps the system predict the actual blood glucose level more precisely, even with the natural delay, to deliver the correct amount of insulin. ## What it does NOT cover - Does not cover glucose monitoring systems that do not actively estimate and compensate for the time delay (latency) between glucose levels in different body compartments. - Does not cover systems that only measure glucose in a single physiological compartment without considering the transport latency between two distinct compartments. - Does not cover glucose monitoring systems that only display readings without generating commands for an infusion pump based on the estimated concentration. - Does not cover systems that do not use at least one blood glucose reference sample to help estimate the latency. - Does not cover compensation methods that do not involve accumulating difference values between a sensor signal and an offset, and combining this with a term including the estimated latency. ## The clever bit The clever part is explicitly estimating and then mathematically compensating for the natural time lag (latency) of an analyte, like glucose, as it moves between different body fluids. This allows for more accurate real-time estimation of blood glucose from a sensor placed in a different body compartment, which is crucial for automated treatment decisions. ## Real-world examples 1. Medtronic MiniMed systems 2. Automated insulin delivery systems (artificial pancreas systems) 3. Continuous Glucose Monitoring (CGM) devices integrated with insulin pumps ## Why it matters Accurate glucose monitoring is critical for managing diabetes, especially for automated insulin delivery systems. The body's fluids, like blood and interstitial fluid, don't change glucose levels at the exact same time. This patent improves the precision of continuous glucose monitoring by accounting for these natural delays, leading to more timely and effective treatment decisions. This directly impacts patient safety and health outcomes by reducing the risk of dangerously high or low blood sugar. ## Frequently asked questions ### What does How Devices Precisely Track Glucose Across Body Compartments cover? This patent describes a method for accurately estimating a person's blood glucose by accounting for the natural time delay in how glucose moves between different body fluids, like blood and the fluid around cells, to better control insulin pumps. ### Who owns patent US 9854998? Medtronic Minimed owns this patent, granted in 2018. ### When does this patent expire? This patent is expected to expire on October 10, 2034, when the invention enters the public domain. ### What is patent US 9854998 cited by? This patent has been cited by 1 later patents that build on its ideas. ### What problem does this patent solve? Accurate glucose monitoring is critical for managing diabetes, especially for automated insulin delivery systems. The body's fluids, like blood and interstitial fluid, don't change glucose levels at the exact same time. This patent improves the precision of continuous glucose monitoring by accounting for these natural delays, leading to more timely and effective treatment decisions. This directly impacts patient safety and health outcomes by reducing the risk of dangerously high or low blood sugar. ### What does this patent NOT cover? Does not cover glucose monitoring systems that do not actively estimate and compensate for the time delay (latency) between glucose levels in different body compartments. **Full plain-English explainer:** https://patentbrief.org/patent/us/9854998/method-andor-system-for-multicompartment-analyte-monitoring **Original patent:** https://patents.google.com/patent/US9854998 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How a Computer System Automatically Adjusts Blood Sugar in Real-Time](https://patentbrief.org/patent/us/8956321/computerized-system-for-blood-chemistry-monitoring) — This patent describes a computerized system that continuously monitors a patient's blood glucose and automatically adjusts insulin and dextrose delivery to keep blood sugar levels stable, especially for critically ill patients. - [Smart Clothing That Compares Pulse Signals from Both Sides of Your Body](https://patentbrief.org/patent/us/20200281484/an-apparatus-for-monitoring-the-pulse-of-a-person-and-a-method-thereof) — This patent describes a piece of clothing, like a t-shirt, with built-in sensors in its sleeves or legs to measure and compare pulse characteristics from different limbs, helping to detect subtle health differences. - [How Two Special Antibodies Find Substances in Body Fluids](https://patentbrief.org/patent/us/4376110/psa-test-for-prostate-cancer) — This patent describes a "sandwich" method using two highly specific, man-made antibodies to detect and measure tiny amounts of specific substances, like disease markers, in a fluid sample. - [How Medical Monitors Adapt Oxygen Alarms to Reduce False Alerts](https://patentbrief.org/patent/us/RE47218/tysabri-dosing) — This patent describes an adaptive alarm system for medical patient monitors that dynamically adjusts oxygen saturation thresholds based on recent patient data, aiming to reduce unnecessary alerts. - [How a Robotic Surgical Tool Clamps Tissue Manually and Automatically](https://patentbrief.org/patent/us/11786761/ultrasonic-robotic-tool-actuation) — This patent describes a surgical tool for robotic operations that can clamp tissue using a motor-driven yoke, but also allows a surgeon to manually control the clamping action.