Title
Spine detection in CT and MR using iterated marginal space learning.
Abstract
Examinations of the spinal column with both, Magnetic Resonance (MR) imaging and Computed Tomography (CT), often require a precise three-dimensional positioning, angulation and labeling of the spinal disks and the vertebrae. A fully automatic and robust approach is a prerequisite for an automated scan alignment as well as for the segmentation and analysis of spinal disks and vertebral bodies in Computer Aided Diagnosis (CAD) applications. In this article, we present a novel method that combines Marginal Space Learning (MSL), a recently introduced concept for efficient discriminative object detection, with a generative anatomical network that incorporates relative pose information for the detection of multiple objects. It is used to simultaneously detect and label the spinal disks. While a novel iterative version of MSL is used to quickly generate candidate detections comprising position, orientation, and scale of the disks with high sensitivity, the anatomical network selects the most likely candidates using a learned prior on the individual nine dimensional transformation spaces. Finally, we propose an optional case-adaptive segmentation approach that allows to segment the spinal disks and vertebrae in MR and CT respectively. Since the proposed approaches are learning-based, they can be trained for MR or CT alike. Experimental results based on 42 MR and 30 CT volumes show that our system not only achieves superior accuracy but also is among the fastest systems of its kind in the literature. On the MR data set the spinal disks of a whole spine are detected in 11.5s on average with 98.6% sensitivity and 0.073 false positive detections per volume. On the CT data a comparable sensitivity of 98.0% with 0.267 false positives is achieved. Detected disks are localized with an average position error of 2.4mm/3.2mm and angular error of 3.9°/4.5° in MR/CT, which is close to the employed hypothesis resolution of 2.1mm and 3.3°.
Year
DOI
Venue
2013
10.1016/j.media.2012.09.007
Medical Image Analysis
Keywords
Field
DocType
Marginal space learning,Spine detection,Spinal disk segmentation,Vertebra segmentation,Generative-discriminative detection
CAD,Object detection,Computer vision,Pattern recognition,Segmentation,Computer-aided diagnosis,Artificial intelligence,Iterated function,Discriminative model,Mathematics,Magnetic resonance imaging,False positive paradox
Journal
Volume
Issue
ISSN
17
8
1361-8415
Citations 
PageRank 
References 
39
1.49
35
Authors
7
Name
Order
Citations
PageRank
B. Michael Kelm125515.41
Michael Wels212910.56
Shaohua Kevin Zhou3139288.97
Sascha Seifert4958.08
Michael Sühling526619.15
Yefeng Zheng61391114.67
Dorin Comaniciu78389601.83