Retrospective Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Jan 28, 2017; 9(1): 10-16
Published online Jan 28, 2017. doi: 10.4329/wjr.v9.i1.10
Impact of contrast-enhanced ultrasound in patients with renal function impairment
Rossano Girometti, Tiziano Stocca, Elena Serena, Antonio Granata, Michele Bertolotto
Rossano Girometti, Institute of Diagnostic Radiology, Department of Medical and Biological Sciences, University of Udine, University Hospital “S. Maria della Misericordia”, 33100 Udine, Italy
Tiziano Stocca, S.O.C. Radiologia, San Giovanni di Dio Hospital, 34170 Gorizia, Italy
Elena Serena, Michele Bertolotto, Department of Radiology, University of Trieste, Cattinara Hospital, Strada di Fiume, 34149 Trieste, Italy
Antonio Granata, UOC di Nefrologia-Dialisi, “San Giovanni di Dio” Hospital, 92100 Agrigento, Italy
Author contributions: Girometti R and Bertolotto M designed the study; Stocca T and Bertolotto M performed examinations; Stocca T, Serena E, Granata A and Bertolotto M analyzed images; Girometti R, Stocca T, Serena E, Granata A and Bertolotto M analyzed data; Girometti R and Bertolotto M wrote the paper.
Institutional review board statement: The study was reviewed and approved by the Ethical Committee of the Friuli Venezia Giulia, Italy.
Informed consent statement: By Italian regulations (Determinazione Ministeriale 20.03.2008, Delibera del 15.12.2011 del Garante per la Protezione dei Dati personali) informed consent acquisition is waived for retrospective studies.
Conflict-of-interest statement: Nothing to disclose.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Correspondence to: Rossano Girometti, MD, Institute of Radiology, Department of Medical and Biological Sciences, University of Udine, University Hospital “S. Maria della Misericordia”, via Colugna, 33100 Udine, Italy.
Telephone: +39-0432-559266 Fax: +39-0432-559867
Received: June 11, 2016
Peer-review started: June 15, 2016
First decision: July 29, 2016
Revised: September 18, 2016
Accepted: November 1, 2016
Article in press: November 2, 2016
Published online: January 28, 2017

To investigate the role of contrast enhanced ultrasound (CEUS) in evaluating patients with renal function impairment (RFI) showing: (1) acute renal failure (ARF) of suspicious vascular origin; or (2) suspicious renal lesions.


We retrospectively evaluated patients addressed to CEUS over an eight years period to rule-out vascular causes of ARF (first group of 50 subjects) or assess previously found suspicious renal lesions (second group of 41 subjects with acute or chronic RFI). After preliminary grey-scale and color Doppler investigation, each kidney was investigated individually with CEUS, using 1.2-2.4 mL of a sulfur hexafluoride-filled microbubble contrast agent. Image analysis was performed in consensus by two readers who reviewed digital clips of CEUS. We calculated the detection rate of vascular abnormalities in the first group and performed descriptive statistics of imaging findings for the second group.


In the first group, CEUS detected renal infarction or cortical ischemia in 18/50 patients (36%; 95%CI: 23.3-50.9) and 1/50 patients (2%; 95%CI: 0.1-12), respectively. The detection rate of infarction was significantly higher (P = 0.0002; McNemar test) compared to color Doppler ultrasonography (10%). No vascular causes of ARF were identified in the remaining 31/50 patients (62%). In the second group, CEUS detected 41 lesions on 39 patients, allowing differentiation between solid lesions (21/41; 51.2%) vs complex cysts (20/41; 48.8%), and properly addressing 15/39 patients to intervention when feasible based on clinical conditions (surgery and cryoablation in 13 and 2 cases, respectively). Cysts were categorized Bosniak II, IIF, III and IV in 8, 5, 4 and 3 cases, respectively. In the remaining two patients, CEUS found 1 pseudolesion and 1 subcapsular hematoma.


CEUS showed high detection rate of renal perfusion abnormalities in patients with ARF, influencing the management of patients with acute or chronic RFI and renal masses throughout their proper characterization.

Keywords: Contrast-enhanced ultrasonography, Renal function impairment, Acute renal failure, Renal infarction, Renal lesions, Renal cysts, Bosniak classification

Core tip: Imaging in patients with renal function impairment (RFI) is challenging because of well-known limitations of conventional color Doppler ultrasound or risks related to the use of contrast media on computed tomography and magnetic resonance imaging. Contrast-enhanced ultrasound is a safer imaging tool in patients with RFI, showing 36% detection rate of renal infarction in patients with acute renal failure of suspicious vascular origin, and the capability of characterizing renal lesions in order to address patients to most proper treatment.