Intermittent Theta Burst Stimulation (iTBS) for Treatment of Chronic Post-Stroke Aphasia: Results of a Pilot Randomized, Double-Blind, Sham-Controlled Trial

BACKGROUND: Research indicates intermittent theta burst stimulation (iTBS) is a potential treatment of post-stroke aphasia. MATERIAL/METHODS: In this double-blind, sham-controlled trial (NCT 01512264) participants were randomized to receive 3 weeks of sham (G(0)), 1 week of iTBS/2 weeks of sham (G(1)), 2 weeks of iTBS/1 week of sham (G(2)), or 3 weeks of iTBS (G(3)). FMRI localized residual language function in the left hemisphere; iTBS was applied to the maximum fMRI activation in the residual language cortex in the left frontal lobe. FMRI and aphasia testing were conducted pre-treatment, at ≤1 week after completing treatment, and at 3 months follow-up. RESULTS: 27/36 participants completed the trial. We compared G(0) to each of the individual treatment group and to all iTBS treatment groups combined (G(1–3)). In individual groups, participants gained (of moderate or large effect sizes; some significant at P<0.05) on the Boston Naming Test (BNT), the Semantic Fluency Test (SFT), and the Aphasia Quotient of the Western Aphasia Battery-Revised (WAB-R AQ). In G(1–3), BNT, and SFT improved immediately after treatment, while the WAB-R AQ improved at 3 months. Compared to G(0), the other groups showed greater fMRI activation in both hemispheres and non-significant increases in language lateralization to the left hemisphere. Changes in IFG connectivity were noted with iTBS, showing differences between time-points, with some of them correlating with the behavioral measures. CONCLUSIONS: The results of this pilot trial support the hypothesis that iTBS applied to the ipsilesional hemisphere can improve aphasia and result in cortical plasticity.