title: Microradiosurgical cortical transections generated by synchrotron radiation.
abstract: OBJECTIVE
  Microplanar X-ray beams (microbeams) originated by synchrotron sources have been delivered to the visual brain cortex regions in rodents to create microscopically narrow lesions. The effects of microbeams mimic those generated by microsurgical subpial transections (also known as multiple subpial transections) but are obtained in a low-invasive way.
  
  
  METHODS
  Image-guided atlas-based microbeam cortical transections have been generated on seven 1 month-old Wistar rats. An array of 10 parallel beams of 25 microns in thickness and spaced of 200 micron center-to-center was centered on the visual cortex and deposited an incident dose of 600 Gy.
  
  
  RESULTS
  The procedure was well tolerated by rats. After recovery, rats showed regular behavior, no sign of gross visual impairment and regular weight gain. After 3 months, rats were sacrificed and brains histologically examined. Cortical transections resembling those obtained through a surgical incision were found over the irradiated region. Remarkable sparing of the cortical columns adjacent to the transections was observed. No sign of radionecrosis was evident at least at this time point.
  
  
  CONCLUSIONS
  The visual brain cortex transected by synchrotron-generated microbeams showed an incision-like path of neuronal loss while adjacent non irradiated columns remained intact. These preliminary findings, to be further investigated also using other techniques, suggest that microbeam radiosurgery can affect the cortex at a cellular level providing a potential novel and attractive tool to study cortical function.
authors.affiliation: Cyberknife Radiosurgery Center, Centro Diagnostico Italiano, via Saint Bon, 20147 Milano, Italy; AB Medica, 31 via Nerviano, 20020 Lainate, Milano, Italy. Electronic address: radiosurgery2000@yahoo.com.
authors.forename: Pantaleo
authors.initials: P
authors.lastname: Romanelli
authors.affiliation: European Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, 38043 Grenoble, France. Electronic address: efardone@neuro.fsu.edu.
authors.forename: Erminia
authors.initials: E
authors.lastname: Fardone
authors.affiliation: I.R.C.C.S. Istituto Neurologico Mediterraneo Neuromed, Località Camerelle, 86077 Pozzilli, Italy. Electronic address: domenico.bucci@neuromed.it.
authors.forename: Domenico
authors.initials: D
authors.lastname: Bucci
authors.affiliation: I.R.C.C.S. Istituto Neurologico Mediterraneo Neuromed, Località Camerelle, 86077 Pozzilli, Italy. Electronic address: giuseppe.battaglia@neuromed.it.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Battaglia
authors.affiliation: European Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, 38043 Grenoble, France. Electronic address: brauer@esrf.fr.
authors.forename: Elke
authors.initials: E
authors.lastname: Bräuer-Krisch
authors.affiliation: European Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, 38043 Grenoble, France. Electronic address: requardt@esrf.fr.
authors.forename: Herwig
authors.initials: H
authors.lastname: Requardt
authors.affiliation: European Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, 38043 Grenoble, France.
authors.forename: Geraldine
authors.initials: G
authors.lastname: Le Duc
authors.affiliation: European Synchrotron Radiation Facility (ESRF), 71 avenue des Martyrs, 38043 Grenoble, France. Electronic address: bravin@esrf.fr.
authors.forename: Alberto
authors.initials: A
authors.lastname: Bravin
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000532:radiotherapy*; D019583:Dose Fractionation, Radiation; D004867:Equipment Design; D008297:Male; D008866:Microsurgery / Q000379:methods*; D016634:Radiosurgery / Q000379:methods*; D011882:Radiotherapy, High-Energy / Q000295:instrumentation* / Q000379:methods; D051381:Rats; D017208:Rats, Wistar; D017356:Synchrotrons / Q000295:instrumentation; D016896:Treatment Outcome; D014793:Visual Cortex / Q000473:pathology / Q000601:surgery*
keywords: Brain cortex; Epilepsy; Microbeam; Synchrotron transections