In response to signing a reimbursement contract with one of the largest insurers in the U.S., shares of Senseonics Holdings (NYSEMKT: SENS), a medical device company focused on blood sugar monitoring, rose 11% as of 10:30 a.m. EDT on Tuesday.Senseonics announced today that Aetna (NYSE: AET) is now offering reimbursement for the company's recently approved Eversense Continuous Glucose Monitoring System (CGM).