title: Semiautomated segmentation of the human spine based on echoplanar images.
abstract: The number of functional magnetic resonance imaging (fMRI) studies performed on the human spinal cord (SC) has considerably increased in recent years. The lack of a validated processing pipeline is, however, a significant obstacle to the spread of SC fMRI. One component likely to be involved in any such pipeline is the process of SC masking, analogous to brain extraction in cerebral fMRI. In general, SC masking has been performed manually, with the incumbent costs of being very time consuming and operator dependent. To overcome these drawbacks, we have developed a tailored semiautomatic method for segmenting echoplanar images (EPI) of human spine that is able to identify the spinal canal and the SC. The method exploits both temporal and spatial features of the EPI series and was tested and optimized on EPI images of cervical spine acquired at 3 T. The dependence of algorithm performance on the degree of EPI image distortion was assessed by computing the displacement warping field that best matched the EPI to the corresponding high-resolution T(2) images. Segmentation accuracy was above 80%, a significant improvement over values obtained with similar approaches, but not exploiting temporal information. Geometric distortion was found to explain about 50% of the variance of algorithm classification efficiency.
authors: MARBILab, Museo storico della fisica e Centro di studi e ricerche Enrico Fermi, c/o Fondazione Santa Lucia, 00179 Rome, Italy.
authors: Giovanni
authors: G
authors: Giulietti
authors: Paul E
authors: PE
authors: Summers
authors: Diana
authors: D
authors: Ferraro
authors: Carlo A
authors: CA
authors: Porro
authors: Bruno
authors: B
authors: Maraviglia
authors: Federico
authors: F
authors: Giove
mesh_terms: D000328:Adult; D000465:Algorithms; D017352:Echo-Planar Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013131:Spine / Q000033:anatomy & histology*; D055815:Young Adult