title: Parkinson disease, brain volumes, and subthalamic nucleus stimulation.
abstract: BACKGROUND
  High-frequency stimulation of the subthalamic nucleus (STN) is an effective treatment for advanced Parkinson disease (PD). The clinical and preoperative predictive factors of the best postoperative outcome have been identified. Radiologic predictive factors were investigated.
  
  
  METHODS
  Forty patients with PD underwent surgery for bilateral STN stimulation. MRI was performed in stereotactic conditions before surgery. Brain parenchyma, caudate nucleus, putamen, pallidum, and red nucleus volumes and the surface of the mesencephalon were measured and normalized as percentages of the intracranial volume. Clinical evaluation was performed 1 month before and 6 months after surgery.
  
  
  RESULTS
  The normalized brain parenchyma volume was lower in patients who were older and had a longer disease duration or a lower frontal score and was not predictive of the postoperative outcome. The residual scores for activities of daily living and parkinsonian motor disability were higher in patients with a smaller normalized mesencephalon. The normalized caudate nucleus volume was predictive of the pre- and postoperative levodopa-equivalent dosage.
  
  
  CONCLUSIONS
  Brain atrophy is not an exclusion criterion for neurosurgery, indicating that patients' neurologic, psychiatric, and neuropsychological characteristics are the best predictive factors for neurosurgery. The fact that a smaller normalized mesencephalon surface was associated with a lower beneficial effect of the subthalamic nucleus stimulation on the parkinsonian motor disability suggests that the normalized mesencephalon surface is a predictive factor of the postoperative outcome.
authors.affiliation: Service de Neuroradiologie, Centre d'Investigation Clinique, Hôpital de la Salpêtrière, Assistance-Publique-Hôpitaux de Paris, France.
authors.forename: F
authors.initials: F
authors.lastname: Bonneville
authors.forename: M L
authors.initials: ML
authors.lastname: Welter
authors.forename: C
authors.initials: C
authors.lastname: Elie
authors.forename: S Tezenas
authors.initials: ST
authors.lastname: du Montcel
authors.forename: D
authors.initials: D
authors.lastname: Hasboun
authors.forename: C
authors.initials: C
authors.lastname: Menuel
authors.forename: J L
authors.initials: JL
authors.lastname: Houeto
authors.forename: A M
authors.initials: AM
authors.lastname: Bonnet
authors.forename: V
authors.initials: V
authors.lastname: Mesnage
authors.forename: B
authors.initials: B
authors.lastname: Pidoux
authors.forename: S
authors.initials: S
authors.lastname: Navarro
authors.forename: P
authors.initials: P
authors.lastname: Cornu
authors.forename: Y
authors.initials: Y
authors.lastname: Agid
authors.forename: D
authors.initials: D
authors.lastname: Dormont
mesh_terms: D000203:Activities of Daily Living; D017668:Age of Onset; D000368:Aged; D000978:Antiparkinson Agents / Q000008:administration & dosage; D001284:Atrophy / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D001921:Brain / Q000473:pathology* / Q000503:physiopathology; D001931:Brain Mapping / Q000379:methods; D046690:Deep Brain Stimulation / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000473:pathology* / Q000503:physiopathology / Q000628:therapy*; D018579:Patient Selection; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D013223:Statistics as Topic; D020531:Subthalamic Nucleus / Q000502:physiology*; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents