%0 Journal Article
%T Examination of anticipated chemical shift and shape distortion effect on materials commonly used in prosthetic socket fabrication when measured using MRI: A validation study
%A Mohammad Reza Safari
%A PhD
%A Philip Rowe
%A PhD
%A Arjan Buis
%A PhD
%J Journal of Rehabilitation Research and Development
%D 2013
%I Rehabilitation Research and Development Service, Department of Veterans Affairs
%R 10.1682/jrrd.2011.09.0159
%X The quality of lower-limb prosthetic socket fit is influenced by shape and volume consistency during the residual limb shape-capturing process (i.e., casting). Casting can be quantified with magnetic resonance imaging (MRI) technology. However, chemical shift artifact and image distortion may influence the accuracy of MRI when common socket/casting materials are used. We used a purpose-designed rig to examine seven different materials commonly used in socket fabrication during exposure to MRI. The rig incorporated glass marker tubes filled with water doped with 1 g/L copper sulfate (CS) and 9 plastic sample vials (film containers) to hold the specific material specimens. The specimens were scanned 9 times in different configurations. The absolute mean difference of the glass marker tube length was 1.39 mm (2.98%) (minimum = 0.13 mm [0.30%], maximum = 5.47 mm [14.03%], standard deviation = 0.89 mm). The absolute shift for all materials was <1.7 mm. This was less than the measurement tolerance of +/¨C2.18 mm based on voxel (three-dimensional pixel) dimensions. The results show that MRI is an accurate and repeatable method for dimensional measurement when using matter containing water. Additionally, silicone and plaster of paris plus 1 g/L CS do not show a significant shape distortion nor do they interfere with the MRI image of the residual limb.
%K accuracy
%K casting
%K chemical shift
%K MRI
%K prosthesis
%K prosthetic socket
%K residual limb
%K residual limb volume
%K shape distortion
%K socket material
%U http://www.rehab.research.va.gov/jour/2013/501/pdf/safari501.pdf