Interhemispheric Functional Connectivity in the Primary Motor Cortex Assessed by Resting-State Functional Magnetic Resonance Imaging Aids Long-Term Recovery Prediction among Subacute Stroke Patients with Severe Hand Weakness

Yu-Sun Min; Jang Woo Park; Eunhee Park; Ae-Ryoung Kim; Hyunsil Cha; Dae-Won Gwak; Seung-Hwan Jung; Yongmin Chang; Tae-Du Jung

doi:10.3390/jcm9040975

Interhemispheric Functional Connectivity in the Primary Motor Cortex Assessed by Resting-State Functional Magnetic Resonance Imaging Aids Long-Term Recovery Prediction among Subacute Stroke Patients with Severe Hand Weakness

J Clin Med. 2020 Apr 1;9(4):975. doi: 10.3390/jcm9040975.

Authors

Yu-Sun Min^{1

2

3}, Jang Woo Park⁴, Eunhee Park^{1

2}, Ae-Ryoung Kim^{1

2}, Hyunsil Cha⁴, Dae-Won Gwak², Seung-Hwan Jung², Yongmin Chang^{4

5

6}, Tae-Du Jung^{1

2}

Affiliations

¹ Department of Rehabilitation Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea.
² Department of Rehabilitation Medicine, Kyungpook National University Hospital, Daegu 41944, Korea.
³ Department of Biomedical Engineering, Seoul National University College of Medicine, Seoul 03080, Korea.
⁴ Department of Medical & Biological Engineering, Kyungpook National University, Daegu 41944, Korea.
⁵ Department of Radiology, Kyungpook National University Hospital, Daegu 41944, Korea.
⁶ Department of Molecular Medicine, School of Medicine, Kyungpook National University, Daegu 41944, Korea.

Abstract

This study aimed to evaluate the usefulness of interhemispheric functional connectivity (FC) as a predictor of motor recovery in severe hand impairment and to determine the cutoff FC level as a clinically useful parameter. Patients with stroke (n = 22; age, 59.9 ± 13.7 years) who presented with unilateral severe upper-limb paresis and were confirmed to elicit no motor-evoked potential responses were selected. FC was measured using resting-state functional magnetic resonance imaging (rsfMRI) scans at 1 month from stroke onset. The good recovery group showed a higher FC value than the poor recovery group (p = 0.034). In contrast, there was no statistical difference in FC value between the good recovery and healthy control groups (p = 0.182). Additionally, the healthy control group showed a higher FC value than that shown by the poor recovery group (p = 0.0002). Good and poor recovery were determined based on Brunnstrom stage of upper-limb function at 6 months as the standard, and receiver operating characteristic curve indicated that a cutoff score of 0.013 had the greatest prognostic ability. In conclusion, interhemispheric FC measurement using rsfMRI scans may provide useful clinical information for predicting hand motor recovery during stroke rehabilitation.

Keywords: functional magnetic resonance imaging; motor cortex; neuronal plasticity; recovery of function; stroke.