Reasons why referring doctors order renal ultrasound contrast studies.

Purpose: To determine the indications for CEUS for renal mass evaluation.

Methods: This retrospective, single-center, IRB-approved, HIPAA compliant study analyzed data from 303 consecutive patients scheduled for a renal CEUS to determine the indications for the examination. A chart review was performed from 05/01/2020 through 05/31/2021 on all patients who received a renal CEUS. The patient demographics were extracted as well as the motivating factor for ordering the examination.

Results: From the 303 patients, 114 were referred because of an indeterminate mass seen on CT and 28 were referred for long-term follow-up of a mass defined as benign or malignant was identified on CT. 9 patients were referred for a CEUS follow-up due to an indeterminate mass on MRI and 6 patients were referred for long-term follow-up of a mass defined as benign or malignant on MRI. 34 patients were referred for follow-up for characterization of a lesion seen on unenhanced ultrasound. 48 patients and 21 patients were referred for long-term follow-up of a previously observed benign or malignant lesion, respectively, seen on CEUS. CEUS was ordered in 21 patients to follow-up a partial nephrectomy and 5 patients for follow-up of a thermal ablation. 7 patients were referred because of a clinical finding.

Conclusion: The main reason for a renal CEUS referral is to characterize a mass which could not be characterized on CT or MRI. Another main indication is for long-term follow-up of lesions to decrease radiation dose. Referrals due to inability to receive CT or MRI contrast or renal insufficiency were minor indications.