To review the Ultrasound (US) and Contrast Enhanced Ultrasound (CEUS) features of renal complex cysts. To describe the role of CEUS in the characterization of renal cysts using the Bosniak classification.

Renal cysts are very common in adults since approximately 50% of patients aged >50 years have at least one. Moreover, their detection is very frequent in clinical practice because of the increasing use of imaging modalities. While simple cysts are fully characterized with ultrasound (US), other lesions require further characterization, which is traditionally obtained by multiphase imaging, such as contrast-enhanced Computer Tomography (CECT) and Magnetic Resonance (MRI). Contrast-enhanced ultrasound (CEUS) has been proved to be a useful imaging modality to characterize complex renal cysts using...

Conventional US has high accuracy in differentiating simple cysts from minimally complex cysts. On baseline US, a simple cyst is defined by the presence of a linear thin wall and anechoic content without septa, calcifications, or solid components. When a simple renal cyst is detected, no further imaging examinations are necessary. However, up to 8% of renal cysts may show a complex pattern defined by the presence of increasing intracystic echogenicity, at least one intracystic septum, wall thickening or solid nodules. In these cases, a...

The Bosniak renal cyst classification is a useful method for diagnosing and suggesting the management of complicated cysts and cystic neoplasm since it correlates the malignant potential of the cysts depending on their features. In addition to that, the Bosniak classification is also accurate for predicting malignancy using CEUS. Although this classification is based on CT and MRI findings, CEUS may replace CT in complex renal cyst evaluation. Some authors have found CEUS sensitivity higher than CT depicting the cystic wall and septa vascularity. Moreover,...

N. Faure Bach; Terrassa/ES - nothing to disclose A. Borrat Padrós; Barcelona/ES - nothing to disclose A. M. Perez; Terrrassa/ES - nothing to disclose L. Esteba; Terrassa/ES - nothing to disclose J. L. Reyes Juarez; Barcelona/ES - nothing to disclose I. Roig; Terrassa/ES - nothing to disclose

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