Pre-/intraoperative diagnosis images in minimally invasive surgery can provide necessary guidance for therapy, hand–eye discoordination occurs when guidance information is displayed away from the surgical area. Three-dimensional (3-D) and augmented reality (AR) visualization techniques can provide better judgement and faster understanding for surgeons compared with traditional two-dimensional information. Binocular vision based 3-D guidance system such as surgical microscope, head-mounted display and surgical robot, have shown significant advantages. However, individual difference between observers induced accuracy inconsistency and visual fatigue limit the application of binocular 3-D technique in clinic. To provide a more intuitive and reliable approach for accurate and less invasiveness clinical treatment, we propose an in situ real 3-D see-through microsurgical guidance system.
We firstly propose an optical enhancement module and corresponding high-accuracy 3-D image rendering method to address the resolution and accuracy limitations that affect the visualization of detailed anatomic structures. Furthermore, a novel see-through microscopic device is proposed to assist surgeons with the superimposition of real 3-D guidance onto the surgical target is magnified by an optical visual magnifier module. The see-through surgical guidance system can provide depth perception and allow multiple viewers to have corresponding perspectives from different directions. Quantitatively evaluations on resolution, viewing angle, image accuracy and superimposed accuracy have demonstrated clinical satisfied results. Average accuracy of 3D image superimposition on surgical target was 0.93 mm±0.41 mm. Phantom and clinical volunteer experiments in neurosurgery and orthopaedic surgery also showed high quality reproduction and accurate superimposition of detailed anatomic structures on magnified surgical target, indicating potential clinical availability.
We believe that the novel microsurgery AR guidance system will open up a better approach to provide reliable and intuitive 3D medical information during surgery and other fields. It also has considerable potential in presenting intuitive 3D information in biology and medical researches. Website: http://at3d.med.tsinghua.edu.cn/en
Keywords: Image-guided microsurgery, Medical integral videography, Real 3-D see-through device