Reduction of Magnetic Resonance Imaging Processing Time for the Assessment of Leg Muscle Volume in Children with Cerebral Palsy
Milla Ceja, Kimberly
University of Delaware
Cerebral palsy (CP) is a movement disorder associated with substantially reduced muscle volume, especially in the lower extremities. A criterion method used to assess muscle volume is magnetic resonance imaging (MRI); however, the processing procedures can be extremely labor intensive. The aim of this study was to determine the proportion and location of magnetic resonance images needed to accurately estimate leg muscle volume in children with CP. To address this aim, the volume of individual leg muscles was assessed in 13 children with spastic CP (4-11 years) using MRI. Muscle volume from the full image set (FIM) was compared to 1- image (1IM) and 3-image (3IM) subsets. Results from 13 subjects and 10 muscles in the leg are presented. Muscle volumes from FIM and 1IM were strongly correlated for the peroneus brevis (r2 = 0.97), gastrocnemius (r2 = 0.80), flexor hallucis longus (r2 = 0.79), tibialis anterior (r2 = 0.78; all p < 0.001), flexor digitorum longus (r2 = 0.74; p = 0.001), tibialis posterior (r2 = 0.71, p = 0.001), extensor digitorum longus (r2 = 0.69, p = 0.001) and peroneus longus (r2 = 0.62, p = 0.001). Muscle volumes from FIM and 1IM were moderately correlated for the extensor hallucis longus (r2 = 0.44, p = 0.013), and soleus (r2 = 0.42, p = 0.016). The relationships between FIM and 3IM vs. between FIM and 1IM were stronger for all muscles (r2 = 0.78 to 0.95, all p < 0.001). The results indicate that total volume of the leg muscles can be estimated with as few as 3 magnetic resonance images in children with CP.