Liu, who is more than half a century old, has been experiencing intermittent panic attacks, dizziness, profuse sweating, confusion and even coma for five years, and has been treated as other diseases for no effect. Not long ago, he came to Beijing Second Artillery General Hospital Hepatobiliary Gastroenterology Center to seek help from Professor Zhou Dinghua. After a comprehensive examination, he was diagnosed with islet cell tumor, and Professor Zhou implemented pancreatic tumor ablation treatment using high-intensity focused ultrasound technology. Recently, Lao Liu’s hypoglycemic symptoms disappeared and his fasting blood sugar was normal, and he was discharged from the hospital. Tip: Because islet cell tumor is an endocrine tumor originating from pancreatic beta cells, it is difficult to be detected by ultrasound, CT, MRI and other imaging examinations, and it is difficult to locate. Islet cell tumor is a rare tumor that is more likely to be misdiagnosed. It mainly presents with symptoms such as panic, shivering, pallor, sweating, tachycardia and other symptoms and psychiatric symptoms such as personality change, confusion, epilepsy, coma, etc. Once diagnosed, it usually requires surgical treatment. Because the tumor was located in the head of the pancreas, pancreaticoduodenectomy was routinely performed to cure the patient completely. Because the islet cell tumor is insidious, it is difficult to locate intraoperatively, and the surgery is complicated and extremely risky. High-intensity focused ultrasound is a new type of tumor thermal ablation technology, which has attracted much attention because it is a non-invasive and non-invasive treatment. The use of high-intensity focused ultrasound skillfully combined with ultrasound imaging technology for islet cell tumor ablation not only has clear localization, precise conformation, safety and reliability, but also can adjust the ultrasound dose in real time according to the ablation effect of tumor and blood sugar level to ensure the integrity of tumor ablation. This patient has been undiagnosed since the onset of symptoms and has been misdiagnosed as epilepsy and psychosis. Islet cell tumors include insulinoma, gastrinoma, pancreatic hyperglycemia, vasoactive intestinal peptide tumor, and pancreatic growth inhibitor tumor that originate from the pancreas. These tumors are small in size but powerful in energy, and their symptoms are mostly manifested as symptoms such as hypoglycemia, hypertension, and obesity. Since islet cell tumors are easily misdiagnosed, they should be treated early once detected clinically, and the high-intensity focused ultrasound and ultrasonography technology will completely change the traditional surgical treatment mode of islet cell tumors.