Accuracy of Measurements of the Structural Reserve for Upper Limb Function in Patients With Moderate-to-Severe Stroke

Yeun Jie Yoo; So Yeon Jun; Eun Jin Park; Youngkook Kim

doi:10.1161/STROKEAHA.123.043109

Accuracy of Measurements of the Structural Reserve for Upper Limb Function in Patients With Moderate-to-Severe Stroke

Stroke. 2023 Jul;54(7):1854-1862. doi: 10.1161/STROKEAHA.123.043109. Epub 2023 Jun 5.

Authors

Yeun Jie Yoo¹, So Yeon Jun², Eun Jin Park³, Youngkook Kim³

Affiliations

¹ Department of Rehabilitation Medicine, St Vincent's Hospital (Y.J.Y.), College of Medicine, The Catholic University of Korea, Seoul.
² Department of Rehabilitation Medicine, Seoul St Mary's Hospital (S.Y.J.), College of Medicine, The Catholic University of Korea, Seoul.
³ Department of Rehabilitation Medicine, Yeouido St Mary's Hospital (E.J.P., Y.K.), College of Medicine, The Catholic University of Korea, Seoul.

PMID: 37272392
DOI: 10.1161/STROKEAHA.123.043109

Abstract

Background: The structural integrity of the corticospinal tract (CST) is an important biomarker of poststroke upper limb recovery. Injured CST undergoes Wallerian degeneration rostrocaudally during the first few months. However, there is no standardized measurement of the structural integrity of the CST. This study aimed to determine the measurement accuracy of the structural integrity of the CST.

Methods: This cross-sectional study included 50 consecutive patients with middle cerebral artery stroke who underwent diffusion tensor imaging upon transfer from the acute stroke unit to the inpatient rehabilitation facility (2018-2022). We evaluated hemiplegic upper limb function using Shoulder Abduction and Finger Extension (SAFE) scores. Fractional anisotropy values representing the structural integrity of the CST were evaluated using 4 region of interest-based and 2 tract-based measurements, including the posterior limb of internal capsule, cerebral peduncle, pons, pontomedullary junction, entire CST, and CST in the brainstem. Multivariate linear regression models and the area under the curve (AUC) were used to determine measurement accuracy for hemiplegic upper limb function.

Results: The structural integrity of the CST at the pontomedullary junction showed the highest explanatory power, followed by the entire CST, in the multivariate linear regression models (adjusted R²=0.459 and 0.425, respectively). The structural integrity of the CST at the pontomedullary junction also showed the highest AUC, followed by the entire CST, in discriminating patients with a SAFE score of <8 or 5 from those with SAFE ≥8 or 5 (SAFE <8: AUC, 0.90 [95% CI, 0.80-1.00]; AUC, 0.83 [0.66-0.99]; SAFE <5: AUC, 0.87 [0.77-0.96]; AUC, 0.83, [0.72-0.95], respectively).

Conclusions: The structural integrity of the CST measured at the pontomedullary junction or entire CST demonstrated the highest accuracy for hemiplegic upper limb function in the subacute phase of stroke.

Keywords: anisotropy; biomarker; corticospinal tract; diffusion tensor imaging; stroke.

MeSH terms

Anisotropy
Cross-Sectional Studies
Diffusion Tensor Imaging* / methods
Hemiplegia / diagnostic imaging
Humans
Pyramidal Tracts / diagnostic imaging
Stroke* / diagnostic imaging
Upper Extremity