Basal glucose =81 mg/dl but insuline =38 mu/ml (insuline/glucose > 0,3 ). symptoms of ipoglycemia... how to exclude an insulinoma? ultrasound?thanks!

Hypoglycemia: To diagnose insulinoma, you need to demonstrate inappropriately high insulin/C-peptide when your glucose is low. A glu of 81 is not low, it is normal. You have symptoms of hypo, but these symptoms are often from something else. Insulinoma is rare. Do not start getting CT/ultrasound etc until you establish the biochemical diagnosis first. An Endocrinologist can help you.