Fig. 3.

Imaging learning model. a Classical learning model: “2D → 3D → 2D”. ① Long and difficult learning process that results in vague 3D structures due to lack of immediate correction. ② Process of clinical practice in which residents must correct and rebuild this structure. b New learning model combining 2D and 3D images: “2D + 3D → 3D → 2D”. ① Accelerated learning process in which structures can be corrected in both a timely and repeated manner, which results in accurate 3D structures. ② Process of clinical practice in which the remembered 3D structures are successfully applied