title: Functional neurosurgery in the MRI environment.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the feasibility of microelectrode recording, electrical stimulation, and electrode position checking during functional neurosurgical procedures (DBS, lesion) in the interventional magnetic resonance imaging (iMRI) environment.
  
  
  METHODS
  Seventy-six surgical procedures for DBS implant or radiofrequency lesion were performed in an open 0.2 T MRI operating room. DBS implants were performed in 54 patients (72 surgical procedures) and unilateral radiofrequency lesions in three for a total of 76 surgeries in 57 patients. Electrophysiological studies including macrostimulation and microelectrode recordings for localization were obtained in the 0.5 to 10 mT fringes of the magnetic field in 51 surgeries. MRI confirmation of the electrode position during the procedure was performed after electrophysiological localization.
  
  
  RESULTS
  The magnetic field associated with the MRI scanner did not contribute significant noise to microelectrode recordings. Anatomical confirmation of electrode position was possible within the MRI artifact from the DBS hardware. Symptomatic hemorrhage was detected in two (2.6 %) patients during the operation. Image quality of the 0.2 T MRI scan was sub-optimal for anatomical localization. However, image fusion with pre-operative scans permitted excellent visualization of the DBS electrode tip in relation to the higher quality 1.5 T MRI anatomical scans.
  
  
  CONCLUSIONS
  This study shows that conventional stereotactic localization, microelectrode recordings, electrical stimulation, implant of DBS hardware, and radiofrequency lesion placement are possible in the open 0.2 T iMRI environment. The convenience of having an imaging modality that can visualize the brain during the operation is ideal for stereotactic procedures.
authors.affiliation: Division of Neurosurgery, School of Medicine, University of California-Los Angeles, 200 UCLA Medical Plaza Suite 504, Los Angeles, CA 90095-7182, USA. adesalles@mednetucla.edu
authors.forename: A A F
authors.initials: AA
authors.lastname: De Salles
authors.forename: L
authors.initials: L
authors.lastname: Frighetto
authors.forename: E
authors.initials: E
authors.lastname: Behnke
authors.forename: S
authors.initials: S
authors.lastname: Sinha
authors.forename: L
authors.initials: L
authors.lastname: Tseng
authors.forename: R
authors.initials: R
authors.lastname: Torres
authors.forename: M
authors.initials: M
authors.lastname: Lee
authors.forename: C
authors.initials: C
authors.lastname: Cabatan-Awang
authors.forename: R
authors.initials: R
authors.lastname: Frysinger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D046690:Deep Brain Stimulation; D005240:Feasibility Studies; D005260:Female; D005917:Globus Pallidus / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D038361:Neuronavigation; D012189:Retrospective Studies; D020531:Subthalamic Nucleus / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D014202:Tremor / Q000628:therapy; D020651:Ventral Thalamic Nuclei / Q000473:pathology / Q000503:physiopathology / Q000601:surgery