Dual contrast-enhanced ultrasound for diagnosis of obstructive diseases in upper urinary tracts

Objective To establish a dual contrast-enhanced ultrasonography(DCEUS)method for diagnosing the upper urinary tract obstructive diseases,and to discuss the diagnosis criterion and value.Methods A total of 147patients with upper urinary tract obstructive diseases underwent dual contrast-enhanced ultrasound examination.A dose of SonoVue solution was directly injected into the renal pelvis via the puncture tube,and the antegrade contrast agent movement within the upper urinary tract was continuously monitored under CPS mode.Meanwhile,intravenous contrast-enhanced ultrasound was performed to observe the capillary filling of the urinary tract and surrounding structures,that is what we called DCEUS.And all the patient received magnetic resonance urography(MRU)and urinary contrast-enhanced CT within one week.With the operative findings and/or postoperative pathology taken as the golden standard,the accuracies of DCEUS and MRU in diagnosing the obstructive levels and severity of upper urinary tract obstruction were compared,and the accuracies of DCEUS and contrast-enhanced CT in diagnosing causes of the obstruction were compared.Results(1)The accuracy of DCEUS inrevealing the obstructive levels were 100%,showing no significant difference with MRU(98.6%)(P0.05).(2)The accuracy of DCEUS in evaluating the severity of upper urinary tract obstruction was 98.6%,which was significantly better than that of MRU(89. 8%,P0.01).(3)The accuracy of DCEUS in diagnosing the obstructive causes was 93.2%,showing no significant difference with contrast-enhanced CT(93.9%,P0.05).(4)No complications were found during renal pelvis puncture or administration of SonoVue in the 147patients,and no late complications were noticed during 1-6months ultrasound follow-up in the 143patients who were followed up.Conclusion DCEUS is a safe,effective method;it can accurately locate the upper urinary tract obstruction and help to make qualitative diagnosis,and combination with percutaneous nephrostomy can yield even better clinical values.