Diabetes mellitus is a metabolic disorder in which the patient presents abnormally high glucose concentrations in blood due to either insufficient insulin production or inability of cells to respond to insulin.Continuous glucose monitoring(CGM)involves highly frequent,repetitive measurements of blood glucose concentration,and allows tight glucose control for improved diabetes care.CGM can be effectively accomplished using minimally invasive,subcutaneously implanted sensors that measure glucose concentration in interstitial fluid(ISF).