TOP - Three Ortogonal Planes : A Program for Determining the Degree of Scoliosis

Abstract: Scoliosis is a congenital disease caused by a complex three dimensional deformity of the spine. Traditionally, the disease is diagnosed by measuring the 2D angle between two vertebrae in the coronal plane, the so called Cobb angle. Many methods have been suggested to obtain a true measure of scoliosis in three dimensions. We suggest a method inspired by automatic image registration techniques to describe the entire curvature using 3D image data from spiral Computed Tomography. The method lets the user view three orthogonal slices of the dataset and interact with them until they match each other visually, thus obtaining information of the six degrees of freedom for a rigid body transformation. This has been implemented in a program that could be run on any computer. The output of the program is a description of the deformity of the spine in the form of position and rotation of each vertebra. Comparison with another metod for calculating vertebrae angles have been done. The other method has a more automatic approach and gives a less detailed description of the full deformity of the spine.