Quantitative evaluation of an automatic segmentation method for 3D reconstruction of intervertebral scoliotic disks from MR images

BMC Medical Imaging

Research Article

Chevrefils Claudia¹  Cheriet Farida²  Aubin Carl-Eric³  Grimard Guy⁴  Miron Marie-Claude⁴ 

[1] Ecole Polytechnique de Montreal, Biomedical Engineering Institute, H3C 3A7, Montreal, QC, Canada;Sainte-Justine University Hospital Center, H3T 1C5, Montreal, QC, Canada;Ecole Polytechnique de Montreal, Biomedical Engineering Institute, H3C 3A7, Montreal, QC, Canada;Sainte-Justine University Hospital Center, H3T 1C5, Montreal, QC, Canada;Department of Computer Engineering and Software, Ecole Polytechnique de Montreal, H3C 3A7, Montreal, QC, Canada;Ecole Polytechnique de Montreal, Biomedical Engineering Institute, H3C 3A7, Montreal, QC, Canada;Sainte-Justine University Hospital Center, H3T 1C5, Montreal, QC, Canada;Department of Mechanical Engineering, Ecole Polytechnique de Montreal, H3C 3A7, Montreal, QC, Canada;Sainte-Justine University Hospital Center, H3T 1C5, Montreal, QC, Canada;

关键词: Intervertebral Disk;    Cobb Angle;    Automatic Segmentation;    Manual Segmentation;    Spin Echo Sequence;   

DOI  :  10.1186/1471-2342-12-26

 received in 2011-11-01, accepted in 2012-07-05,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundFor some scoliotic patients the spinal instrumentation is inevitable. Among these patients, those with stiff curvature will need thoracoscopic disk resection. The removal of the intervertebral disk with only thoracoscopic images is a tedious and challenging task for the surgeon. With computer aided surgery and 3D visualisation of the interverterbral disk during surgery, surgeons will have access to additional information such as the remaining disk tissue or the distance of surgical tools from critical anatomical structures like the aorta or spinal canal. We hypothesized that automatically extracting 3D information of the intervertebral disk from MR images would aid the surgeons to evaluate the remaining disk and would add a security factor to the patient during thoracoscopic disk resection.MethodsThis paper presents a quantitative evaluation of an automatic segmentation method for 3D reconstruction of intervertebral scoliotic disks from MR images. The automatic segmentation method is based on the watershed technique and morphological operators. The 3D Dice Similarity Coefficient (DSC) is the main statistical metric used to validate the automatically detected preoperative disk volumes. The automatic detections of intervertebral disks of real clinical MR images are compared to manual segmentation done by clinicians.ResultsResults show that depending on the type of MR acquisition sequence, the 3D DSC can be as high as 0.79 (±0.04). These 3D results are also supported by a 2D quantitative evaluation as well as by robustness and variability evaluations. The mean discrepancy (in 2D) between the manual and automatic segmentations for regions around the spinal canal is of 1.8 (±0.8) mm. The robustness study shows that among the five factors evaluated, only the type of MRI acquisition sequence can affect the segmentation results. Finally, the variability of the automatic segmentation method is lower than the variability associated with manual segmentation performed by different physicians.ConclusionsThis comprehensive evaluation of the automatic segmentation and 3D reconstruction of intervertebral disks shows that the proposed technique used with specific MRI acquisition protocol can detect intervertebral disk of scoliotic patient. The newly developed technique is promising for clinical context and can eventually help surgeons during thoracoscopic intervertebral disk resection.

【 授权许可】

Unknown   
© Chevrefils et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.