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Transcranial magnetic stimulation over the anterior cingulate cortex improves blepharospasm, according to a new study. The results suggest that the ACC is involved in the pathophysiology of blepharospasm, and that TMS may provide a noninvasive therapeutic approach to treatment. Seven patients with blepharospasm received low-frequency (0.2 Hz) repetitive TMS (lfrTMS) for 15 minutes (a total of 180 stimuli) to each of four brain areas: motor cortex, premotor cortex, supplementary motor area, and ACC. Stimulation sessions were separated by at least 2 days. Video recording of blepharospasm was evaluated by a blinded observer before and after stimulation. lfrTMS over all four areas led to improvement in blepharospasm, in contrast to two other techniques, continuous theta burst stimulation and transcranial direct stimulation, which led to no significant improvement. lfrTMS of the ACC led to an approximately 30% improvement in symptoms compared to baseline as rated by the blinded observer, an approximately 20% improvement as rated by the patient, and an approximately 10% improvement in the blink reflex recovery. Stimulation of the SMA and PMC led to smaller improvements in physician and patient rating, and slightly larger improvements in blink reflex recovery. The electrophysiologic effect of the lfrTMS was inhibitory, suggesting that "hypersensitivity of the ACC is directly or indirectly involved in the pathophysiology of benign essential blepharospasm," the authors conclude. "Inhibition of these areas using lfrTMS could provide a therapeutic tool and is worthy of a larger study." Blepharospasm and the modulation of cortical excitability in primary and secondary motor areas G Kranz, EA Shamin, PT Lin, GS Kranz, B Voller, M Hallett Neurology 2009;73:2031-2036 ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn