title: Technique for the computation of lower leg muscle bulk from magnetic resonance images.
abstract: An unsupervised technique to estimate the relative size of a patient's lower leg musculature in vivo using magnetic resonance imaging (MRI) in the context of venous insufficiency is presented. This post-acquisition technique was designed to segment calf muscle bulk, which could be used to make inter- or intra-patient comparisons of calf muscle size in the context of unilateral leg ulcers and venous return. Pre-processing stages included partial volume reduction, intensity inhomogeneity correction and contrast equalization. The algorithm created a binary mask of voxels that fell within a computed threshold designated as representing muscle based on a 3-class fuzzy clustering approach. The segmentation was improved using a set of morphological operations to remove adipose tissue, spongy bone and cortical bone. The technique was evaluated for accuracy against a manual segmented ground truth. Results showed that the automatic technique performed sufficiently well in terms of accuracy and efficacy. The automatic method did not suffer from intra-observer variability.
authors.affiliation: Electrical & Electronic Engineering, National University of Ireland Galway, University Road, Galway, Ireland. b.broderick2@nuigalway.ie
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Broderick
authors.forename: Sylvain
authors.initials: S
authors.lastname: Dessus
authors.forename: Pierce A
authors.initials: PA
authors.lastname: Grace
authors.forename: Gearóid
authors.initials: G
authors.lastname: Olaighin
mesh_terms: D000465:Algorithms; D016477:Artifacts; D017143:Fuzzy Logic; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007866:Leg; D008279:Magnetic Resonance Imaging; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D015588:Observer Variation; D009929:Organ Size; D015203:Reproducibility of Results