Imaging Laterality in Chronic Stroke Patients

Summary

In healthy individuals, unimanual movement (with either the left or right hand) is associated with activity in a network of predominantly contralateral brain regions, including the primary motor cortex (PMC). This laterality is often compromised following a middle cerebral artery (MCA) stroke. Neuroimaging studies of these patients have shown that unimanual movements with the effected hand are associated with elevated Blood Oxygen-Level Dependent (BOLD) signal in both the lesioned and the nonlesioned primary motor cortices. Elevated activity in the contralesional PMC is well-established in chronic stroke patients and is associated with poor motor rehabilitation outcomes. Yet the neurobiologic basis for this aberrant neural activity is equivocal. The overarching goal of this project is to determine the neurobiologic basis for elevated activity in the contralesional primary motor cortex.

Conditions

• Stroke
• Motor Cortex; Lesion

Interventions

DIAGNOSTIC_TEST

Rasch modified version of the Fugl-Meyer Motor assessment

All participants will receive a comprehensive clinical assessment of motor function including the Rasch modified version of the Fugl-Meyer Motor assessment and a kinematic assessment of unimanual and bimanual movements using a 45 sensor 3D active marker based motion capture system. The three primary measures investigated in the kinematics include: 1) movement efficiency, 2) movement smoothness, and 3) motor compensation.

DIAGNOSTIC_TEST

Anatomical image acquisition

High-resolution structural scans will be obtained using an inversion recovery 3D spoiled gradient echo (3DSPGR) sequence using a matrix size of 256 x 256, field of view of 24 cm, section thickness of 1.5 mm with no gap between sections, and 128 slices, giving an in-plane resolution of 0.94 mm. This sequence will be used for anatomic overlays of the functional data and for spatial normalization to a standard atlas.

DIAGNOSTIC_TEST

Functional MRI task and acquisition

Briefly, patients will be given two pressure-sensitive bulbs (one to be held in each hand and fastened lightly to their wrists with Velcro such that they do not drop it during the scan. During two 2½ minute runs they will be prompted to squeeze the bulb in either their affected or unaffected hand in blocks of 15 seconds. These blocks will be interspersed with blocks of rest. The pressure from the bulbs will be digitally recorded and quantified offline in order to: 1) verify that the patient was squeezing the ball, and 2) assess the presence of 'mirror movements' from the opposing hand that may inform the imaging results regarding loss of laterality).

Sponsors & Collaborators

• MUSC Center for Biomedical Research Excellence in Stroke Recovery

  collaborator UNKNOWN

• Medical University of South Carolina

  lead OTHER

Principal Investigators

• Colleen A Hanlon, PhD · Medical University of South Carolina

Study Design

Allocation

NON_RANDOMIZED

Purpose

DIAGNOSTIC

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

21 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2014-12-15

Primary Completion

2019-05-30

Completion

2019-05-30

Countries

• United States

Study Locations