Title
Automatic Location of Vertebrae on DXA Images Using Random Forest Regression.
Abstract
We provide a fully automatic method of segmenting vertebrae in DXA images. This is of clinical relevance to the diagnosis of osteoporosis by vertebral fracture, and to grading fractures in clinical trials. In order to locate the vertebrae we train detectors for the upper and lower vertebral endplates. Each detector uses random forest regressor voting applied to Haar-like input features. The regressors are applied at a grid of points across the image, and each tree votes for an endplate centre position. Modes in the smoothed vote image are endplate candidates, some of which are the neighbouring vertebrae of the one sought. The ambiguity is resolved by applying geometric constraints to the connections between vertebrae, although there can be some ambiguity about where the sequence starts (e.g. is the lowest vertebra L4 or L5, Fig 2a). The endplate centres are used to initialise a final phase of Active Appearance Model search for a detailed solution. The method is applied to a dataset of 320 DXA images. Accuracy is comparable to manually initialised AAM segmentation in 91% of images, but multiple grade 3 fractures can cause some edge confusion in severely osteoporotic cases.
Year
DOI
Venue
2012
10.1007/978-3-642-33454-2_45
Lecture Notes in Computer Science
Field
DocType
Volume
Computer vision,Confusion,Pattern recognition,Computer science,Segmentation,Active appearance model,Artificial intelligence,Vertebra,Random forest
Conference
7512
Issue
ISSN
Citations 
Pt 3
0302-9743
10
PageRank 
References 
Authors
0.67
9
3
Name
Order
Citations
PageRank
Martin G. Roberts1272.36
Timothy F. Cootes24358579.15
Judith E. Adams3535.57