Ultrasound simulators: experience with the SonoTrainer and comparative review of other training systems

Ultrasound has become indispensable in prenatal diagnosis. Ultrasound training, however, still lacks proper quality assessment and control. Moreover, most fetal anomalies which must be diagnosed during pregnancy are extremely rare. Ultrasound simulators could provide an opportunity to overcome this dilemma. This review summarizes the potential benefits of simulator-based ultrasound training, briefly describes the properties of a variety of ultrasound simulators that have been developed for various applications including prenatal diagnosis, and presents the SonoTrainer sonography simulation system which makes it possible to run a real-time simulation of a complete prenatal ultrasound examination. We evaluated the system for the training of first- and second-trimester screening for both normal and pathological findings and found that physicians who received theoretical training and were additionally trained with the simulator (T + S) significantly improved their skills in measurements of nuchal translucency thickness (NT) and crown-rump length (CRL) as compared with colleagues who only underwent theoretical instruction (T) [mean +/- SD NT deviation: 0.31 +/- 0.1 mm (T + S) vs. 0.62 +/- 0.2 mm (T), P < 0.05; mean +/- SD CRL deviation: 1.48 +/- 2.0 mm (T + S) vs. 3.27 +/- 2.5 (T), P < 0.05]. Simulator-based training enabled physicians to diagnose rare fetal anomalies in the second trimester with a sensitivity of 86% and a specificity of 100%. In a study in which second-trimester scans including fetal anomalies were presented to physicians, 96% of the participants subjectively estimated their training effect as being good. We therefore conclude that simulator-based training would provide an ideal educational tool to test, improve and monitor a physician's or technician's ultrasound skills in detecting fetal anomalies.