Article

Prognosis of long-term motor outcome of acute stroke patients with
severe motor impairment is difficult to determine. OBJECTIVE: Our primary goal
was to evaluate the prognostic value of corticospinal tract (CST) injury on motor
outcome of the upper limb compared with motor impairment level and lesion volume.
METHODS: In all, 10 acute stroke patients with moderately severe to severe motor
impairment of the upper limb underwent diffusion tensor imaging (DTI) and testing
of upper limb strength and dexterity at acute, subacute, and chronic poststroke
time points. A density-weighted CST atlas was constructed using DTI tractography
data from normal participants. This CST atlas was applied, using a largely
automated process, to DTI data from patients to quantify CST injury at each time
point. Differences in axial diffusivity (AD), radial diffusivity (RD), and
fractional anisotropy (FA) of the ipsilesional CST relative to the contralesional
CST were measured. RESULTS: Acute loss in CST AD correlated most strongly and
significantly with subacute and chronic strength and dexterity and remained
significant after adjusting for acute motor impairment or lesion volume. Subacute
loss in CST FA correlated most strongly with chronic dexterity, whereas subacute
behavioral measures of limb strength correlated most strongly with chronic
strength measures. CONCLUSIONS: Loss in acute CST AD and subacute CST FA are
strong prognostic indicators of future motor functions of the upper limb for
stroke patients with substantial initial motor impairment. DTI-derived measure of
CST injury early after stroke may have utility in health care planning and in
design of acute stroke clinical trials.
CI - (c) The Author(s) 2014.

Langue : ANGLAIS