Contrast-Enhanced Ultrasound (CEUS) for Follow-Up of Bosniak 2F Complex Renal Cystic Lesions-A 12-Year Retrospective Study in a Specialized European Center.

Bosniak 2F renal cystic lesions feature morphologic characteristics between Bosniak I and III categories, the majority of which remain benign. However, a minor part of Bosniak 2F lesions may progress to malignancy. The purpose of this study was to assess Bosniak 2F cystic lesions during follow-up examinations by CEUS. One-hundred-and-twelve out of 364 patients with Bosniak 2F lesions underwent follow-up CEUS examinations between February 2008 and February 2020. Twelve out of 364 patients underwent renal surgery without follow-up CEUS. The progression rate of Bosniak 2F renal lesions detected by CEUS accounted for 7.1% (8/112 patients) after a mean of 12.9 months. The first follow-up CEUS revealed 75% of progressions (6/8), the remaining 25% (2/8) of progressions were detected during second follow-up CEUS. Underlying clear-cell renal cell carcinoma was histopathologically validated in 5/8 progressive complex cystic renal lesions. Stable sonomorphologic features were observed in 92.1% (104/112 patients). CEUS depicts a promising diagnostic imaging modality in the diagnostic work-up and follow-up of complex renal cystic lesions at higher spatial and temporal resolutions than CT or MRI. Its excellent safety profile, its easy and repeatable accessibility, and low financial costs render CEUS an attractive and powerful alternative imaging tool for monitoring complex renal cystic lesions.

Contrast-Enhanced Ultrasound in the Follow-Up of Endoleaks after Endovascular Aortic Repair (EVAR).

Endovascular aortic repair (EVAR) has become established in the treatment of abdominal aortic aneurysms and shows potential benefits such as a low perioperative morbidity and a short hospitalization duration. The follow-up after EVAR primarily consists of lifelong postinterventional imaging of the aneurysm size in order to detect complications such as endoleaks or stent dislocation. Computed tomography angiography, an imaging modality that uses ionizing radiation and that relies on a contrast medium which is dependent on thyroid and renal function, is widely used for follow-up. Meanwhile, contrast-enhanced ultrasound (CEUS) has been established as a viable, fast and cost-effective imaging alternative for the follow-up and the detection of endoleaks after EVAR with the additional benefit of being a real-time non-ionizing radiation examination and having comparable or even superior diagnostic performance. This review describes the use of CEUS for follow-up after EVAR and describes the most common pathologies.