During the last two decades three-dimensional (3D) ultrasound has become increasingly popular around the world. There have been a great number of research papers studying its feasibility as well as reliability and accuracy. Compared to two-dimensional (2D), 3D ultrasound produces better visualization with minimal probe manipulation. The sonographer performing 2D ultrasound has to mentally assemble crosssectional images of a structure and/or object into a 3D image. In cases with uncertain anatomic orientation less experienced examiners may experience difficulties in envisioning three dimensions of the visualized structure, lesion or organ. Patients and parents are often faced with similar problems. A number of studies have shown that novice operators can efficiently store and interpret the volume data by 3D ultrasound, which may have many positive implications in the practice.