Semi-automated segmentation of magnetic resonance images for thigh skeletal muscle and fat using threshold technique after spinal cord injury

After spinal cord injury (SCI), reduced physical activity leads to muscle loss and increased fat below the injury site. MRI is the preferred method for measuring muscle and fat in the thigh. Manual tracing of muscle groups on MRI images is reliable but time-consuming and subjective. It can take 1–1.5 years to analyze data from 20 SCI patients, pushing researchers to use less accurate methods. This study validates a semi-automated threshold technique for MRI image segmentation to measure thigh muscle compartments after SCI, aiming to provide an accurate and faster tool.

• 1
  The threshold technique accurately measures thigh circumference, subcutaneous adipose tissue, whole muscle, femoral bone, bone marrow fat, knee extensor, and intramuscular fat cross-sectional areas in men with SCI.
• 2
  The threshold technique showed a high level of agreement with manual tracing, proving its robustness in quantifying muscle, fat, and bone compartments in SCI patients.
• 3
  The semi-automated technique reduced analysis time by approximately 80% compared to manual segmentation, analyzing 216 images in one hour per subject.