Effect of repetitive transcranial magnetic stimulation in a patient with chronic crossed aphasia: fMRI study

We report here the case of a 52-year-old Korean woman who was initially diagnosed with non-fluent/global crossed aphasia.

Initial computed tomography of the brain revealed a haematoma of approximately 40 ml in the right basal ganglia area and cavitation around the right lateral ventricle. Three years after onset the aphasia was resolved to a conduction aphasia and she had an ongoing left-sided gait disturbance. Follow-up anatomical magnetic resonance imaging found no recurrence of haemorrhage. Language functional magnetic resonance imaging was examined before and after repetitive transcranial magnetic stimulation treatment. A 90-mm round coil stimulator was used and the repetitive transcranial magnetic stimulation treatment location was P3 on the 10-20 International electrode placement system (1 Hz, 20 min per day for 10 days over a 2-week period). Functional magnetic resonance imaging results before repetitive transcranial magnetic stimulation treatment showed no significant activity in either the ipsilesional or contralesional hemispheres for noun generation and sentence completion paradigms (p < 0.001, cluster size 128). Compared with the pre-treatment phase, following repetitive transcranial magnetic stimulation treatment the data from functional magnetic resonance imaging revealed significant activations in the right inferior frontal lobe (Broca's area), posterior temporal gyrus (Wernicke's area), and parietal lobe for both the noun generation and sentence completion tasks (p < 0.001, cluster size 128).

This functional magnetic resonance imaging case study is the first to suggest the use of repetitive transcranial magnetic stimulation for improving language outcome in a patient with crossed aphasia. In addition, we report the value of language functional magnetic resonance imaging before and after repetitive transcranial magnetic stimulation treatment for determining the effect of treatment and the underlying neurobiological mechanism of functional recovery following repetitive transcranial magnetic stimulation treatment.