Implantable Fluorescence Sensing (Eversense)

The Eversense system by Senseonics (distributed by Ascensia) is the market's only long-term implantable CGM, utilizing optical fluorescence rather than electrochemical oxidation. The sensor uses a phenylboronic acid hydrogel that fluoresces in the presence of glucose. It is a passive device powered via inductive coupling by a removable external transmitter, eliminating internal batteries.

To combat the Foreign Body Response (FBR), the sensor elutes dexamethasone to prevent fibrosis, enabling wear times of 90 to 365 days. Unlike modern transcutaneous CGMs, Eversense generally requires daily calibration via fingerstick, maintaining a clinical reliance on high-accuracy diabetic test strips (specifically Ascensia's Contour Next line) to ensure data fidelity.