title: Parkinson's disease outcomes after intraoperative CT-guided "asleep" deep brain stimulation in the globus pallidus internus.
abstract: OBJECTIVE
  Recent studies show that deep brain stimulation can be performed safely and accurately without microelectrode recording ortest stimulation but with the patient under general anesthesia. The procedure couples techniques for direct anatomical targeting on MRI with intraoperative imaging to verify stereotactic accuracy. However, few authors have examined the clinical outcomes of Parkinson's disease (PD) patients after this procedure. The purpose of this study was to evaluate PD outcomes following "asleep" deep brain stimulation in the globus pallidus internus (GPi).
  
  
  METHODS
  The authors prospectively examined all consecutive patients with advanced PD who underwent bilateral GPi electrode placement while under general anesthesia. Intraoperative CT was used to assess lead placement accuracy. The primary outcome measure was the change in the off-medication Unified Parkinson's Disease Rating Scale motor score 6 months after surgery. Secondary outcomes included effects on the 39-Item Parkinson's Disease Questionnaire (PDQ-39) scores, on-medication motor scores, and levodopa equivalent daily dose. Lead locations, active contact sites, stimulation parameters, and adverse events were documented.
  
  
  RESULTS
  Thirty-five patients (24 males, 11 females) had a mean age of 61 years at lead implantation. The mean radial error off plan was 0.8 mm. Mean coordinates for the active contact were 21.4 mm lateral, 4.7 mm anterior, and 0.4 mm superior to the midcommissural point. The mean off-medication motor score improved from 48.4 at baseline to 28.9 (40.3% improvement) at 6 months (p < 0.001). The PDQ-39 scores improved (50.3 vs 42.0; p = 0.03), and the levodopa equivalent daily dose was reduced (1207 vs 1035 mg; p = 0.004). There were no significant adverse events.
  
  
  CONCLUSIONS
  Globus pallidus internus leads placed with the patient under general anesthesia by using direct anatomical targeting resulted in significantly improved outcomes as measured by the improvement in the off-medication motor score at 6 months after surgery.
authors.affiliation: Divisions of 1 Neurological Surgery.
authors.forename: Zaman
authors.initials: Z
authors.lastname: Mirzadeh
authors.affiliation: Divisions of 1 Neurological Surgery.
authors.forename: Kristina
authors.initials: K
authors.lastname: Chapple
authors.affiliation: Divisions of 1 Neurological Surgery.
authors.forename: Margaret
authors.initials: M
authors.lastname: Lambert
authors.affiliation: Movement Disorders Center of Arizona, Scottsdale; and.
authors.forename: Virgilio G
authors.initials: VG
authors.lastname: Evidente
authors.affiliation: Banner Good Samaritan Medical Center, Phoenix, Arizona.
authors.forename: Padma
authors.initials: P
authors.lastname: Mahant
authors.affiliation: Banner Good Samaritan Medical Center, Phoenix, Arizona.
authors.forename: Maria C
authors.initials: MC
authors.lastname: Ospina
authors.affiliation: Banner Good Samaritan Medical Center, Phoenix, Arizona.
authors.forename: Johan
authors.initials: J
authors.lastname: Samanta
authors.affiliation: Neurology, and.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Moguel-Cobos
authors.affiliation: Neurology, and.
authors.forename: Naomi
authors.initials: N
authors.lastname: Salins
authors.affiliation: Neurology, and.
authors.forename: Abraham
authors.initials: A
authors.lastname: Lieberman
authors.affiliation: Clinical Neuropsychology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix;
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Tröster
authors.affiliation: Neurology, and.
authors.forename: Rohit
authors.initials: R
authors.lastname: Dhall
authors.affiliation: Divisions of 1 Neurological Surgery.
authors.forename: Francisco A
authors.initials: FA
authors.lastname: Ponce
mesh_terms: D046690:Deep Brain Stimulation / Q000379:methods*; D004567:Electrodes, Implanted; D005260:Female; D005917:Globus Pallidus / Q000601:surgery*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods*; D010300:Parkinson Disease / Q000628:therapy*; D011446:Prospective Studies; D012890:Sleep; D013238:Stereotaxic Techniques; D025321:Surgery, Computer-Assisted / Q000379:methods*; D011795:Surveys and Questionnaires; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: ADL = activity of daily living; DBS = deep brain stimulation; FGATIR = fast gray matter acquisition T1 inversion recovery; GPi = globus pallidus internus; MDS = International Parkinson and Movement Disorder Society; MER = microelectrode recording; PD = Parkinson’s disease; PDQ-39 = 39-Item Parkinson’s Disease Questionnaire; Parkinson’s disease; STN = subthalamic nucleus; UPDRS-III = Unified Parkinson’s Disease Rating Scale Part III; deep brain stimulation; functional neurosurgery; intraoperative imaging; stereotactic accuracy