title: Automatic Myonuclear Detection in Isolated Single Muscle Fibers Using Robust Ellipse Fitting and Sparse Representation.
abstract: Accurate and robust detection of myonuclei in isolated single muscle fibers is required to calculate myonuclear domain size. However, this task is challenging because: 1) shape and size variations of the nuclei, 2) overlapping nuclear clumps, and 3) multiple z-stack images with out-of-focus regions. In this paper, we have proposed a novel automatic detection algorithm to robustly quantify myonuclei in isolated single skeletal muscle fibers. The original z-stack images are first converted into one all-in-focus image using multi-focus image fusion. A sufficient number of ellipse fitting hypotheses are then generated from the myonuclei contour segments using heteroscedastic errors-in-variables (HEIV) regression. A set of representative training samples and a set of discriminative features are selected by a two-stage sparse model. The selected samples with representative features are utilized to train a classifier to select the best candidates. A modified inner geodesic distance based mean-shift clustering algorithm is used to produce the final nuclei detection results. The proposed method was extensively tested using 42 sets of z-stack images containing over 1,500 myonuclei. The method demonstrates excellent results that are better than current state-of-the-art approaches.
authors.forename: Hai
authors.initials: H
authors.lastname: Su
authors.forename: Fuyong
authors.initials: F
authors.lastname: Xing
authors.forename: Jonah D
authors.initials: JD
authors.lastname: Lee
authors.forename: Charlotte A
authors.initials: CA
authors.lastname: Peterson
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
mesh_terms: D000465:Algorithms; D000818:Animals; D002467:Cell Nucleus / Q000502:physiology*; D016000:Cluster Analysis; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008853:Microscopy; D018485:Muscle Fibers, Skeletal / Q000166:cytology*