Relationship between mental rotation ability, clinical experience and navigation performance in simulated prenatal sonography

Prenatal sonography can provide crucial information for patient care. A central part in this subspecialty is navigating to a target cut plane to acquire an image for inspection and, therefore, the determinants of navigation performance in prenatal sonography should be explored. In this study, we tested the relationship between mental rotation (MR) ability, clinical experience and navigation performance to a target cut plane in prenatal sonography. Thirty sonographers completed an MR test (MRT-A) and were asked to navigate to a target cut plane, using a simulator. We analyzed the number of errors that sonographers made on their way to the target, the duration of their navigation, and their final distance from the target. The number of errors and the duration of navigation were analyzed according to two phases: Phase 1 - from the starting point of the navigation to a perimeter where sonographers could view their target organ (i.e., femur bones) and Phase 2 - from the perimeter to the perspective (target cut plane) of the organ that sonographers were asked to acquire. We found that higher mental rotation (MR) ability reduced the number of errors and the duration of navigation in Phase 1, but not in Phase 2. We also found that greater experience reduced the number of errors all the way to the target cut plane but reduced the duration of navigation only in Phase 2. In addition, we found that both higher MR ability and greater experience reduced the final distance from the target cut plane. Finally, our findings demonstrated that the number of errors in Phase 2 was approximately 32 times greater than in Phase 1, suggesting that sonographers might have engaged in frequent trial and error during their navigation in Phase 2. Our findings suggest that training programs for prenatal sonography should be designed to support sonographers with lower MR ability by placing greater weight on how to make 3D inferences from 2D data and on how to use such inferences for navigation. In addition, our findings suggest that navigation in prenatal sonography is a two-phase process and therefore, that navigation performance should be studied according to the phase of navigation. Future studies should test if navigation performance affects the quality of diagnosis in prenatal sonography.