<prompt> Answer this question truthfullyWhat is the role of ultrasound in the diagnosis of glucagonoma?  <response>: <reason> The abdominal ultrasound scan may be helpful in the diagnosis of glucagonoma. Finding on ultrasound scan suggestive of glucagonoma is a hypoechoic tumor in the distal pancreas. US-guided fine-needle aspiration biopsy is a non-operative histologic diagnosis. Intraoperative ultrasonography is used as an adjunct to intraoperative palpation. 