Inclusion Criteria:  1.age ≥6 years old 2.Patients with hypoglycaemia 3.Endogenous hyperinsulinemic hypoglycaemia 4.Enhanced CT or MRI within 1 month 5.Signed written consent  Exclusion Criteria:  1. Breast feeding 2.Pregnancy or the wish to become pregnant within 6 months 3.Renal function: serum creatinine during 41-73umol/L 4.Any medical condition may significantly interfere with study compliance; 5.Known allergy