Affiliations: Department of Radiation Oncology, University of North
Carolina at Chapel Hill, NC, USA | Department of Physics and Astronomy, University of
North Carolina at Chapel Hill, NC, USA | Curriculum of Applied and Materials Sciences,
University of North Carolina at Chapel Hill, NC, USA | Lineberger Comprehensive Cancer Center, University of
North Carolina at Chapel Hill, NC, USA
Note: [] Address for correspondence: Sigen Wang or Sha Chang, Department
of Radiation Oncology, University of North Carolina at Chapel Hill, NC 27599,
USA. Tel.: +1 919 966 1101; Fax: +1 919 966 7681; E-mail:
sgwang@email.unc.edu/sxchang@med.unc.edu
Abstract: Micro-radiotherapy (micro-RT) system is specially designed for small
animal (cancer cell) irradiation for basic and translational cancer research.
We use carbon nanotube (CNT) field emission technology to develop a novel
micro-RT system for image-guided high precision irradiation that is similar to
the state of the art radiotherapy which our cancer patients receive today at
mouse scale. Through the field emission control of its individually addressable
x-ray pixel beams the micro-RT system electronically shapes the radiation field
and forms intensity modulation pattern. In this paper, we present the
development of a carbon nanotube field emission cathode array chip – a key
component for our novel micro-RT system. The prototype micro-RT CNT field
emission cathode array chip has 5 × 5 individually
addressable cathode pixels that are 1 mm in diameter and 2 mm in pitch. An
individual CNT cathode pixel is predicted to generate a dose rate in the order
of 100 cGy/min at the center of the irradiated mouse based on our Monte Carlo
simulation. The temporal and spatial resolutions of the micro-RT system are
expected to be ∼ ms level and < 2 mm respectively.
Keywords: Cancer treatment, micro-radiotherapy (micro-RT) system, small animal model, carbon nanotubes, field emission
Journal: BioFactors, vol. 30, no. 4, pp. 265-270, 2007
