Application of parametric ultrasound contrast agent perfusion studies for differentiation of hyperplastic adrenal nodules from adenomas-Initial study

Abstract

Objectives: To evaluate the possibilities of differentiation of non-malignant adrenal masses with the application of the new technique for the evaluation of enhancement after administration of an ultrasound contrast agent: parametric imaging.

Patients and methods: 34 non-malignant adrenal masses in 29 patients were evaluated in a dynamic examination after the administration of ultrasound contrast agent with parametric imaging. Patterns on parametric imaging of arrival time were evaluated. The final diagnosis was based on CT, MRI, biochemical studies, follow up and/or histopathology examination.

Results: The study included: 12 adenomas, 10 hyperplastic nodules, 7 myelolipomas, 3 pheochromocytomas, hemangioma with hemorrhage and cyst. The pattern of peripheral laminar inflow of Sonovue on parametric images of arrival time of was 100% sensitive for hyperplastic nodules and 83% specific in regard to adenomas.

Conclusions: Parametric contrast enhanced ultrasound may accurately differentiate hyperplastic adrenal nodules from adenomas and could be complementary to CT or MRI. Incorporation of perfusion studies to CT or MRI could possibly enable one-shop complete characterization of adrenal masses. This could deliver additional information in diagnostics of patients with Conn Syndrome and warrants further studies in this cohort of patients.

Keywords: Adrenal gland diseases; Adrenal hyperplasia; Perfusion imaging; Ultrasound.