title: Grey Matter Microstructural Integrity Alterations in Blepharospasm Are Partially Reversed by Botulinum Neurotoxin Therapy.
abstract: OBJECTIVE
  Benign Essential Blepharospasm (BEB) and hemifacial spasm (HFS) are the most common hyperkinetic movement disorders of facial muscles. Although similar in clinical presentation different pathophysiological mechanisms are assumed. Botulinum Neurotoxin (BoNT) is a standard evidence-based treatment for both conditions. In this study we aimed to assess grey matter microstructural differences between these two groups of patients and compared them with healthy controls. In patients we furthermore tracked the longitudinal morphometric changes associated with BoNT therapy. We hypothesized microstructural differences between the groups at the time point of maximum symptoms representation and distinct longitudinal grey matter dynamics with symptom improvement.
  
  
  METHODS
  Cross-sectional and longitudinal analyses of 3T 3D-T1 MRI images from BEB, HFS patients prior to and one month after BoNT therapy and from a group of age and sex matched healthy controls. Cortical thickness as extracted from Freesurfer was assessed as parameter of microstructural integrity.
  
  
  RESULTS
  BoNT therapy markedly improved motor symptoms in patients with BEB and HFS. Significant differences of grey matter integrity have been found between the two patients groups. The BEB group showed lower cortical thickness at baseline in the frontal-rostral, supramarginal and temporal regions compared to patients with HFS. In this group BoNT treatment was associated with a cortical thinning in the primary motor cortex and the pre-supplementary motor area (pre-SMA). Contrary patients with HFS showed no longitudinal CT changes. A decreased cortical thickness was attested bilaterally in the temporal poles and in the right superior frontal region in BEB patients in comparison to HC. Patients in the HFS group presented a decreased CT in the left lingual gyrus and temporal pole.
  
  
  CONCLUSIONS
  Although patients with BEB and HFS present clinically with involuntary movements of facial muscles, they exhibited differences in cortical thickness. While BoNT therapy was equally effective in both groups, widespread changes of cortical morphology occurred only in BEB patients. We demonstrated specific disease- and therapy-dependent structural changes induced by BoNT in the studied hyperkinetic conditions.
authors.affiliation: Department of Neurology, University of Kiel, Kiel, Germany.
authors.forename: Hanganu
authors.initials: H
authors.lastname: Alexandru
authors.affiliation: Department of Neurology, University of Kiel, Kiel, Germany.|Movement Disorders and Neurostimulation, Department of Neurology, Neuroimage Center (NIC) of the Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
authors.forename: Muthuraman
authors.initials: M
authors.lastname: Muthuraman
authors.affiliation: Movement Disorders and Neurostimulation, Department of Neurology, Neuroimage Center (NIC) of the Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
authors.forename: Venkata Chaitanya
authors.initials: VC
authors.lastname: Chirumamilla
authors.affiliation: Movement Disorders and Neurostimulation, Department of Neurology, Neuroimage Center (NIC) of the Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
authors.forename: Nabin
authors.initials: N
authors.lastname: Koirala
authors.affiliation: Department of Neurology, University of Kiel, Kiel, Germany.
authors.forename: Burcu
authors.initials: B
authors.lastname: Paktas
authors.affiliation: Department of Neurology, University of Kiel, Kiel, Germany.
authors.forename: Günther
authors.initials: G
authors.lastname: Deuschl
authors.affiliation: Department of Neurology, University of Kiel, Kiel, Germany.
authors.forename: Kirsten E
authors.initials: KE
authors.lastname: Zeuner
authors.affiliation: Department of Neurology, University of Kiel, Kiel, Germany.|Movement Disorders and Neurostimulation, Department of Neurology, Neuroimage Center (NIC) of the Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.
authors.forename: Sergiu
authors.initials: S
authors.lastname: Groppa
mesh_terms: D000328:Adult; D000368:Aged; D001764:Blepharospasm / Q000000981:diagnostic imaging / Q000188:drug therapy*; D001905:Botulinum Toxins / Q000008:administration & dosage* / Q000494:pharmacology; D003430:Cross-Sectional Studies; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging* / Q000187:drug effects; D019569:Hemifacial Spasm / Q000000981:diagnostic imaging / Q000188:drug therapy*; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
chemical_list: D001905:Botulinum Toxins