Application of multiple slice spiral CT (MSCT) postprocessing technique in scoliosis

Objective: To study further clinical value of multi-slice spiral CT (MSCT) postprocessing technique in patients with scoliosis. Methods: Radiological image data in 26 cases with scoliosis that have been performed operation to correct the defomity between January 2006 and January 2008 were studied retrospectively. All cases were performed with preoperative X-ray, multi-slice spiral CT scan. And all the images were reformed by Multiple Planar Reconstruction, Curved Planar Reconstruction (MRP/CPR), Maximum Intensity Projection(MIP), 3D-Surface Shaded Display(3D-SSD),4D-angio and Volume Rendering Technique (VRT), which were used to evaluate the value of the various images. The postoperative relative position of the screw to the pedicle and vertebra was investigated and to evaluate the advantages and disadvantages of MSCT of different postprocessing in scoliosis. Results: Among 26 cases, Cobb's angle range was from 35 degree to 128 degree. There were 17 idiopathic scoliosis and 5 congenital scoliosis, 2 neuro fibromatosis scoliosis, and one other according to clinical classification MRP/CPR techniques were easily used for scoliosis with coronary and sagittal image. It may offer many potential advantages for defining spine anomalies liable to cause progression of scoliosis, including visualization of the deformity in any plane, from any angle, with the overlying structures subtracted. 3D-SSD was suitable to show the whole of the spinal structure and the angle of scoliosis, but failed to display the content of the vertebral canal. It was always useful if there is extensive bony tissue. VRT could directly and clearly show all of the anatomy of scoliosis through adjusting the density threshold, such as modality of complex anomalies, osteal pathological changes, and related condition about scoliosis, it was especially suitable for the classification of scoliosis and displaying the status of the vertebral canal It was valuable for surgical operation. 4D-anglo was the best in use for evaluation all related signs in scoliosis. MIP technique could only provide poor effect and was not suitable for evaluation of scoliosis. Conclusion: MSCT can be used for scanning of the whole spine in one time, and post-processing techniques can provide accurately the space structure of scoliosis which appears to be an effective modality to assess the pedicle screw position, and it is of important value for spine doctor to set down surgical plan in individual patient. (authors)