Premium
Bone marrow segmentation based on a combined consideration of transverse relaxation processes and Dixon oscillations
Author(s) -
Balasubramanian Mukund,
Jarrett Delma Y.,
Mulkern Robert V.
Publication year - 2016
Publication title -
nmr in biomedicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.278
H-Index - 114
eISSN - 1099-1492
pISSN - 0952-3480
DOI - 10.1002/nbm.3498
Subject(s) - thresholding , bone marrow , signal (programming language) , transverse plane , subtraction , segmentation , image subtraction , sampling (signal processing) , nuclear magnetic resonance , biomedical engineering , materials science , acoustics , physics , image processing , computer science , anatomy , medicine , image (mathematics) , pathology , artificial intelligence , mathematics , optics , binary image , arithmetic , detector , programming language
The aim of this study was to demonstrate that gradient‐echo sampling of single spin echoes can be used to isolate the signal from trabecular bone marrow, with high‐quality segmentation and surface reconstructions resulting from the application of simple post‐processing strategies. Theoretical expressions of the time‐domain single‐spin‐echo signal were used to simulate signals from bone marrow, non‐bone fatty deposits and muscle. These simulations were compared with and used to interpret signals obtained by the application of the gradient‐echo sampling of a spin‐echo sequence to image the knee and surrounding tissues at 1.5 T. Trabecular bone marrow has a much higher reversible transverse relaxation rate than surrounding non‐bone fatty deposits and other musculoskeletal tissues. This observation, combined with a choice of gradient‐echo spacing that accentuates Dixon‐type oscillations from chemical‐shift interference effects, enabled the isolation of bone marrow signal from surrounding tissues through the use of simple image subtraction and thresholding. Three‐dimensional renderings of the marrow surface were then readily generated with this approach – renderings that may prove useful for bone morphology assessment, e.g. for the measurement of femoral anteversion. In conclusion, understanding the behavior of signals from bone marrow and surrounding tissue as a function of time through a spin echo facilitates the segmentation and reconstruction of bone marrow surfaces using straightforward post‐processing strategies that are typically available on modern radiology workstations. Copyright © 2016 John Wiley & Sons, Ltd.