title: Bilateral impairment of intracortical inhibition in delayed-onset posthemiplegic dystonia: pathophysiological implications.
abstract: OBJECTIVE
  To study short interval intracortical inhibition (SICI) in a rare patient with segmental dystonia of the left upper limb due to a vascular lesion in the contralateral putamen without corticospinal tract involvement.
  
  
  METHODS
  Paired-pulse transcranial magnetic stimulation (TMS) was applied to both hemispheres in a conditioning-test paradigm. Six interstimulus intervals (ISIs) and 4 conditioning stimulation intensities were investigated in two separate sessions.
  
  
  RESULTS
  Motor evoked potentials upon single-pulse TMS were within the normal range, whereas paired-pulse TMS revealed major changes in cortical excitability, proving that SICI was bilaterally absent.
  
  
  CONCLUSIONS
  The bilateral impairment of SICI cannot be considered the cause of dystonic contractions, but just a predisposing factor.
  
  
  CONCLUSIONS
  The absence of SICI might be regarded as a condition able to promote maladaptive plastic changes triggered by focal lesions in the putamen.
authors: Department of Neurosciences, Ophthalmology and Genetics, University of Genoa, Via de Toni, 5, 16132 Genova, Italy.
authors: Carlo
authors: C
authors: Trompetto
authors: Alessandro
authors: A
authors: Buccolieri
authors: Marco
authors: M
authors: Bove
authors: Gianpaolo
authors: G
authors: Brichetto
authors: Laura
authors: L
authors: Avanzino
authors: Lucio
authors: L
authors: Marinelli
authors: Giovanni
authors: G
authors: Abbruzzese