title: Fiber-optic detector for real time dosimetry of a micro-planar x-ray beam.
abstract: OBJECTIVE
  Here, the authors describe a dosimetry measurement technique for microbeam radiation therapy using a nanoparticle-terminated fiber-optic dosimeter (nano-FOD).
  
  
  METHODS
  The nano-FOD was placed in the center of a 2 cm diameter mouse phantom to measure the deep tissue dose and lateral beam profile of a planar x-ray microbeam.
  
  
  RESULTS
  The continuous dose rate at the x-ray microbeam peak measured with the nano-FOD was 1.91 ± 0.06 cGy s(-1), a value 2.7% higher than that determined via radiochromic film measurements (1.86 ± 0.15 cGy s(-1)). The nano-FOD-determined lateral beam full-width half max value of 420 μm exceeded that measured using radiochromic film (320 μm). Due to the 8° angle of the collimated microbeam and resulting volumetric effects within the scintillator, the profile measurements reported here are estimated to achieve a resolution of ∼0.1 mm; however, for a beam angle of 0°, the theoretical resolution would approach the thickness of the scintillator (∼0.01 mm).
  
  
  CONCLUSIONS
  This work provides proof-of-concept data and demonstrates that the novel nano-FOD device can be used to perform real-time dosimetry in microbeam radiation therapy to measure the continuous dose rate at the x-ray microbeam peak as well as the lateral beam shape.
authors.affiliation: Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 and Duke Radiation Dosimetry Laboratory, Duke University Medical Center, Durham, North Carolina 27710.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Belley
authors.affiliation: Department of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708.
authors.forename: Ian N
authors.initials: IN
authors.lastname: Stanton
authors.affiliation: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599.
authors.forename: Mike
authors.initials: M
authors.lastname: Hadsell
authors.affiliation: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599.
authors.forename: Rachel
authors.initials: R
authors.lastname: Ger
authors.affiliation: Department of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708.
authors.forename: Brian W
authors.initials: BW
authors.lastname: Langloss
authors.affiliation: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599.
authors.forename: Jianping
authors.initials: J
authors.lastname: Lu
authors.affiliation: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599 and UNC Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina 27599.
authors.forename: Otto
authors.initials: O
authors.lastname: Zhou
authors.affiliation: Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599; Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina 27599; and UNC Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina 27599.
authors.forename: Sha X
authors.initials: SX
authors.lastname: Chang
authors.affiliation: Department of Chemistry, Duke University, 124 Science Drive, Durham, North Carolina 27708.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Therien
authors.affiliation: Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705;Duke Radiation Dosimetry Laboratory, Duke University Medical Center, Durham, North Carolina 27710; and Department of Radiology, Duke University Medical Center, Durham, North Carolina 27710.
authors.forename: Terry T
authors.initials: TT
authors.lastname: Yoshizumi
mesh_terms: D000818:Animals; D002138:Calibration; D004867:Equipment Design; D005336:Fiber Optic Technology / Q000295:instrumentation*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles; D019047:Phantoms, Imaging; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods; D011878:Radiotherapy / Q000295:instrumentation / Q000379:methods; D014964:X-Ray Therapy / Q000295:instrumentation / Q000379:methods; D014965:X-Rays
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