Differences in Brain Adaptive Functional Reorganization in Right and Left Total Brachial Plexus Injury Patients.
OBJECTIVE
Total brachial plexus avulsion injury (BPAI) results in the total functional loss of the affected limb and induces extensive brain functional reorganization. However, because the dominant hand is responsible for more cognitive-related tasks, injuries on this side induce more adaptive changes in brain function. In this article, we explored the differences in brain functional reorganization after injuries in unilateral BPAI patients.


METHODS
We applied resting-state functional magnetic resonance imaging scanning to 10 left and 10 right BPAI patients and 20 healthy control subjects. The amplitude of low-frequency fluctuation (ALFF), which is a resting-state index, was calculated for all patients as an indication of the functional activity level of the brain. Two-sample t-tests were performed between left BPAI patients and controls, right BPAI patients and controls, and between left and right BPAI patients.


RESULTS
Two-sample t-tests of the ALFF values revealed that right BPAIs induced larger scale brain reorganization than did left BPAIs. Both left and right BPAIs elicited a decreased ALFF value in the right precuneus (P < 0.05, Alphasim corrected). In addition, right BPAI patients exhibited increased ALFF values in a greater number of brain regions than left BPAI patients, including the inferior temporal gyrus, lingual gyrus, calcarine sulcus, and fusiform gyrus.


CONCLUSIONS
Our results revealed that right BPAIs induced greater extents of brain functional reorganization than left BPAIs, which reflected the relatively more extensive adaptive process that followed injuries of the dominant hand.
Department of Hand Surgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
Jun-Tao
JT
Feng
Department of Radiology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
Han-Qiu
HQ
Liu
Department of Hand Surgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
Jian-Guang
JG
Xu
Department of Hand Surgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
Yu-Dong
YD
Gu
Department of Hand Surgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China. Electronic address: yundongshen@126.com.
Yun-Dong
YD
Shen
D000328:Adult; D001917:Brachial Plexus / Q000293:injuries*; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009778:Occipital Lobe / Q000503:physiopathology; D010296:Parietal Lobe / Q000503:physiopathology; D013702:Temporal Lobe / Q000503:physiopathology; D055815:Young Adult
Amplitude of low frequency fluctuation; Brachial plexus avulsion injury; Brain reorganization; Hand dominance; Resting-state fMRI