Article

Correlating the features of the actual executed movement with the
associated cortical activations can enhance the reliability of the functional
Magnetic Resonance Imaging (fMRI) data interpretation. This is crucial for
longitudinal evaluation of motor recovery in neurological patients and for
investigating detailed mutual interactions between activation maps and movement
parameters.Therefore, we have explored a new set-up combining fMRI with an
optoelectronic motion capture system, which provides a multi-parameter
quantification of the performed motor task. METHODS: The cameras of the motion
system were mounted inside the MR room and passive markers were placed on the
subject skin, without any risk or encumbrance. The versatile set-up allows
3-dimensional multi-segment acquisitions including recording of possible mirror
movements, and it guarantees a high inter-sessions repeatability.We demonstrated
the integrated set-up reliability through compatibility tests. Then, an fMRI
block-design protocol combined with kinematic recordings was tested on a healthy
volunteer performing finger tapping and ankle dorsal- plantar-flexion. A
preliminary assessment of clinical applicability and perspectives was carried out
by pre- and post rehabilitation acquisitions on a hemiparetic patient performing
ankle dorsal- plantar-flexion. For all sessions, the proposed method integrating
kinematic data into the model design was compared with the standard analysis.
RESULTS: Phantom acquisitions demonstrated the not-compromised image quality.
Healthy subject sessions showed the protocols feasibility and the model
reliability with the kinematic regressor. The patient results showed that brain
activation maps were more consistent when the images analysis included in the
regression model, besides the stimuli, the kinematic regressor quantifying the
actual executed movement (movement timing and amplitude), proving a significant
model improvement. Moreover, concerning motor recovery evaluation, after one
rehabilitation month, a greater cortical area was activated during exercise, in
contrast to the usual focalization associated with functional recovery. Indeed,
the availability of kinematics data allows to correlate this wider area with a
higher frequency and a larger amplitude of movement. CONCLUSIONS: The kinematic
acquisitions resulted to be reliable and versatile to enrich the fMRI images
information and therefore the evaluation of motor recovery in neurological
patients where large differences between required and performed motion can be
expected.

Langue : ANGLAIS