Letter to the Editor on the Article: “Comparison of Magnetic Resonance Imaging and Contrast-Enhanced Ultrasound as Diagnostic Options for Unclear Cystic Renal Lesions: A Cost-Effectiveness Analysis” - Spiesecke, Paul; Reinhold, Thomas; Lerchbaumer, Markus Herbert (Ultraschall in der Medizin - European Journal of Ultrasound, 2021)