Surface reconstruction of torsos with and without scoliosis.

Visible surface asymmetries such as uneven shoulders, waist and hips, shoulder height differences and a shoulder blade prominence are often the most troublesome features associated with adolescent scoliosis. Treatment considerations are influenced by the severity and changes over time of these asymmetries. Outcomes are judged on how well the asymmetries are improved towards a normal trunk shape. In this paper, a deformable self organizing feature map (SOFM) is used as a geometric surface reconstruction tool to model the torso surface of subjects with and without scoliosis. The proposed parameterization technique provides a means of quantifying the surface asymmetries and assessing the changes due to either natural history or the effects of treatment. For evaluation 10 control subjects without scoliosis and 10 adolescents with scoliosis were scanned and their torsos were reconstructed. This preliminary study demonstrates that in around 5 min a torso scan with 60,000 data points can be transformed into a 2562 nodes mesh using SOFM. The accuracy of the final mesh is around 1.40 mm on average. The high accuracy and speed of this technique, makes it well suitable to be used in a clinical setting to assess surface features of subjects with scoliosis.