Noninvasive Brain Stimulations for Unilateral Spatial Neglect after Stroke: A Systematic Review and Meta-Analysis of Randomized and Nonrandomized Controlled Trials

Abstract

Background Unilateral spatial neglect (USN) is the most frequent perceptual disorder after stroke. Noninvasive brain stimulation (NIBS) is a tool that has been used in the rehabilitation process to modify cortical excitability and improve perception and functional capacity. Objective To assess the impact of NIBS on USN after stroke. Methods An extensive search was conducted up to July 2016. Studies were selected if they were controlled and noncontrolled trials examining transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and theta burst stimulation (TBS) in USN after stroke, with outcomes measured by standardized USN and functional tests. Results Twelve RCTs (273 participants) and 4 non-RCTs (94 participants) proved eligible. We observed a benefit in overall USN measured by the line bisection test with NIBS in comparison to sham (SMD −2.35, 95% CI −3.72, −0.98; p = 0.0001); the rTMS yielded results that were consistent with the overall meta-analysis (SMD −2.82, 95% CI −3.66, −1.98; p = 0.09). The rTMS compared with sham also suggested a benefit in overall USN measured by Motor-Free Visual Perception Test at both 1 Hz (SMD 1.46, 95% CI 0.73, 2.20; p < 0.0001) and 10 Hz (SMD 1.19, 95% CI 0.48, 1.89; p = 0.54). There was also a benefit in overall USN measured by Albert's test and the line crossing test with 1 Hz rTMS compared to sham (SMD 2.04, 95% CI 1.14, 2.95; p < 0.0001). Conclusions The results suggest a benefit of NIBS on overall USN, and we conclude that rTMS is more efficacious compared to sham for USN after stroke.

Repetitive transcranial magnetic stimulation in stroke rehabilitation: review of the current evidence and pitfalls

“…In detail, the results included the following: seven studies for motor function, 62–68 three for manual dexterity, 69–71 three for walking and balance, 72–74 three for spasticity, 64,75,76 six for dysphagia, 77–82 five for aphasia, 83–87 three for unilateral neglect, 88–90 three for post-stroke depression and vascular depression, 66,91,92 one for cognitive function, 66 and one for CPSP. 93 The study by Graef and colleagues 64 included data on both motor function and spasticity and, therefore, the results were independently considered for both categories.…”

“…90 According to the most recent meta-analysis on the same topic, the benefits of rTMS seem to be particularly evident when 1 Hz frequency of stimulation is used. 88…”

Influence of Static Magnetic Field Stimulation on the Accuracy of Tachystoscopically Presented Line Bisection

“…However, no treatment for neglect has been established thus far. As reported in three recent reviews about the effectiveness of NIBS on USN symptoms [ 29 , 31 , 70 ], inhibitory rTMS is one of the promising tools for future treatment, but TMS is expensive and requires a quite high-level of technical skill for its use. On the other hand, the NdFeB magnet is an inexpensive industrial product that is easily available, and application of the magnet on the scalp does not require a high operational skill.…”

Noninvasive Brain Stimulation and Noninvasive Peripheral Stimulation for Neglect Syndrome Following Acquired Brain Injury

“…[64][65][66] The use of NIBS to modulate cortical activity in a target area in patients with neglect was the topic of three recent meta-analysis. [67][68][69] However, the authors found no clear positive effect of NIBS for the treatment of neglect following stroke. Some limitations in the scope of these meta-analysis must be pointed out: first, only cerebrovascular disease patients were included; secondly, the authors did not evaluate the type of sham used in the experiments and the blinding of evaluators, and third, the results suffered from bias due to small number of patients and strong heterogeneity of the protocol of NIBS applied with only few randomized controlled studies retrieved.…”