title: Three-dimensional (3-D) reconstruction of the spine from a single X-ray image and prior vertebra models.
abstract: The lateral bending test is routinely used by clinicians for the preoperative assessment of spinal mobility. The evaluation of bending motion is usually based on the qualitative analysis of a two-dimensional (2-D) antero-posterior X-ray image. The aim of this paper is to introduce a novel three-dimensional (3-D) reconstruction technique that is a prerequisite for the quantitative 3-D analysis of lateral bending motion. An algorithm was developed for the 3-D reconstruction of the spine from a single X-ray image. The X-ray is calibrated using a small calibration object and an explicit calibration algorithm. The information contained in the single X-ray is completed by registering a priori 3-D geometric models of individual vertebrae. Part of the error yielded by the 3-D/2-D registration is corrected by a vertebral alignment constraint that aims to minimize intervertebral dislocations. Three-dimensional models of 15 different scoliosis patients, obtained from a standard stereo-radiographic 3-D reconstruction, were used in simulation and validation experiments. Experimental results show that the new method is robust and accurate. With pessimistic levels of simulated noise, the average root mean square reconstruction error is 2.89 mm, which is appropriate for common clinical applications.
authors.affiliation: Ecole Polytechnique de Montreal and the Sainte-Justine Hospital Research Center, Montreal, QC H3T 1C5, Canada. justin.novosad@ieee.org
authors.forename: Justin
authors.initials: J
authors.lastname: Novosad
authors.forename: Farida
authors.initials: F
authors.lastname: Cheriet
authors.forename: Yvan
authors.initials: Y
authors.lastname: Petit
authors.forename: Hubert
authors.initials: H
authors.lastname: Labelle
mesh_terms: D000465:Algorithms; D001185:Artificial Intelligence; D002138:Calibration; D016000:Cluster Analysis; D003198:Computer Simulation; D021621:Imaging, Three-Dimensional / Q000295:instrumentation / Q000379:methods*; D016247:Information Storage and Retrieval / Q000379:methods; D008954:Models, Biological; D015233:Models, Statistical; D010363:Pattern Recognition, Automated; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000295:instrumentation / Q000379:methods; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D015203:Reproducibility of Results; D012600:Scoliosis / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013131:Spine / Q000000981:diagnostic imaging*; D013382:Subtraction Technique