Accuracy of rib cage parameters from 3-Dimensional reconstruction images obtained using simultaneous biplanar radiographic scanning technique in adolescent idiopathic scoliosis: Comparison with conventional computed tomography.

Simultaneous biplanar radiographic scanning technique (EOS) (EOS Imaging, Paris, France) variability has previously been evaluated for spinal parameters, however limited EOS data exist regarding accuracy of 3-dimensional (3D) rib cage reconstruction. The purpose of this study was to compare the evaluation of ribcage parameter between EOS 3D images and 3D computed tomography (CT) images from adolescent idiopathic scoliosis (AIS) patients, and validate the accuracy of EOS 3D ribcage reconstruction images. In total, 31 AIS patients (27 females, 4 males; mean age 14.4 years) with Lenke types 1 or 2 who underwent corrective surgery were enrolled. EOS 3D images were assessed preoperatively for all patients. Rib cage parameters were measured, including surface spinal penetration index (sSPI), endothoracic hump ratio (EHR), vertebra-sternum angle (VSA), rib-vertebral angle difference (RVAD) at apex and vertebral lateral decentering (VLD). Measurements were subsequently compared with CT images. No significant differences were observed in sSPI or EHR measurements between EOS and CT images. Measured VSA values from EOS and CT were -28.1 degrees and -26.1 degrees, respectively. Measured RVAD values from EOS and CT were 13.0 degrees and 12.0 degrees, respectively. No significant differences were observed for measured VSA or RVAD values between EOS and CT images. Measured VLD values from EOS and CT were 68.5% and 67.5%, respectively, representing similar values. The accuracy of rib cage parameters measured with EOS software is similar to the measurements obtained with CT. The results of this study provide surgeons with important evidence pertaining to this novel imaging technology.