Lumbar Vertebral With Spondylolisthesis And Ligamentum Flavum Model Building Based On 3-D Printing

Objective: Extract modeling data by exploring and making use of CT and MRI statistics and then combine the data with 3-D printing technology to design and construct a digital model of the lumbar and ligamentum flavum so as to realize a new way of modeling spondylolisthesis and ligamentum flavum by printing skeletal tissue and soft tissue simultaneously. Method: Choose a NO.5 lumbar vertebral degree II spondylolisthesis patient and conduct CT and MR scan. Then use Mimics, a medical 3D reconstruction software, to conduct pre-process of the data in the DICOM pictures: perform threshold segmentation, smoothing, hole-filling and repairing on each vertebra after extracting CT data and then do outlining, extracting and reconstruction to the spondylolisthesis tissue morphology of the MRI image material to construct a CAD model of the entity. Next, do post processing to the model by using 3D Max and import the file into Magics 19.01 and then detect the repaired model by conducting the repair function of the application. Finally, export STL pictures and print the model by SLA Stereo Lithography Apparatus. Result: Using CT and MRI statistics to extract modeling data and 3D printing technology to make resin model of the spine guaranteed the morphological consistence with CAD model. It reflected the morphology and anatomical structure of the centrum and its ligamentum flavum objectively and accurately. The spondylolisthesis, spondylolysis, and zygapophyseal joints are clear to see. Compared with the two-dimension of imaging data, this model is more visualized and stereo. Conclusion: Using CT and MR statistics to extract modeling data and 3D printing technology to construct model make it possible to 3D print vertebra and ligamentum flavum simultaneously and find out more ways to conduct 3D print of vertebra and ligamentum flavum.