Long-term effects of continuous theta-burst stimulation in visuospatial neglect

Abstract

Objective: To investigate whether the efficacy of continuous theta-burst stimulation (cTBS) for improving visuospatial neglect can be enhanced by providing more days of stimulation and more stimulation trains per day. Methods: In a prospective study, right-handed patients with right hemisphere stroke and visuospatial neglect were randomized to cTBS or sham cTBS treatment for 2 weeks and were followed up for 4 weeks. The cTBS group received active cTBS over the posterior parietal cortex of the unaffected hemisphere, combined with conventional rehabilitation therapy. Changes in scores for two paper-pencil tests for visuospatial neglect (star cancellation and line bisection) were evaluated. Results: In each group, 10 patients completed follow up. Compared with the sham group, star cancellation test scores in the cTBS group were improved by 37.03% at the end of treatment and by 47.21% after 4 weeks' follow up, and the line bisection score improved by 21.37% at the end of treatment and by 35.99% after 4 weeks' follow up. Conclusions: These results suggest that the efficacy of cTBS in visuospatial neglect can be enhanced and prolonged by increasing the days of stimulation and the number of stimulation trains per day over the left posterior parietal cortex.

Transcranial Magnetic Stimulation as an Intervention Tool to Recover from Language, Swallowing and Attentional Deficits after Stroke: A Systematic Review

“…Spatial neglect, that is, the inability to attend, reply, react or orient to stimuli located in the contralesional portion of space, [1,2,8,9,[20][21][22] affects from 30 to 81% of patients in the acute phase [8,9] and it is sustained in approximately a third of them [9]. It appears most often due to right hemispheric lesions of the middle cerebral artery, damaging the neural substrates of space representation and awareness [2,8,23].…”

“…The search for new methods able to increase the efficacy of recovery programs is crucial [17,20]. It is well recognized that, following stroke, the balance of function between the hemispheres is disturbed and the affected hemisphere becomes more inhibited, while the hemisphere contralateral to the lesion shows an increased activity [3,25,26].…”

“…These were published between 2009 and 2016. The literature applied cTBS [1,20] or LF-rTMS [8,9,21,22] to the unaffected hemisphere over posterior parietal cortex or HF-rTMS to the stroke affected hemisphere, [8] as an adjuvant to conventional therapy. Moreover, Cha and Kim [23] applied LF-rTMS over P3, based on the International 10/20 system, and Yang et al [2] stimulated the contralateral posterior parietal cortex either with cTBS, LF-rTMS or HF-rTMS.…”

“…Furthermore, the treatment effects were superior for Cerebrovasc Dis 2018;46:176-183 DOI: 10.1159/000494213 allocentric compared to egocentric neglect, which was explained by the fact that allocentric neglect patients had wider brain lesions and, thereafter, more severe baseline symptoms [21]. Fu et al [20] provided initial evidence that increasing number of training runs per day and of stimulation days might enhance and lengthen cTBS efficacy on improvement of visuospatial neglect.…”

“…The authors also assumed that this difference could have been originated by the functional heterogeneity of patients [2]. Fu et al [20] suggested that applying a combination of multiple neglect tests could be more sensitive than using only a test to detect and define the presence of visuospatial neglect.…”