Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.

A Study of Radiation Necrosis and Edema in the Canine Brain Using Positron Emission Tomography and Magnetic Resonance Imaging

Kathleen M. Brennan, Mark S. Roos, Thomas F. Budinger, Robert J. Higgins, Sam T. S. Wong and Kay S. Bristol
Radiation Research
Vol. 134, No. 1 (Apr., 1993), pp. 43-53
DOI: 10.2307/3578500
Stable URL: http://www.jstor.org/stable/3578500
Page Count: 11
  • Read Online (Free)
  • Download ($10.00)
  • Subscribe ($19.50)
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
A Study of Radiation Necrosis and Edema in the Canine Brain Using Positron Emission Tomography and Magnetic Resonance Imaging
Preview not available

Abstract

Radiation injury, a major hazard of central nervous system (CNS) radiotherapy, was investigated using sequential studies with positron emission tomography (PET) and magnetic resonance imaging (MRI) in beagle dogs with both helium and neon-ion hemibrain irradiation. All dogs receiving 7.5-11 Gy of neon showed no signs of radiation injury to 3 years after irradiation. Dogs receiving ≥13 Gy neon or helium succumbed to radiation necrosis and died 21-32 weeks after irradiation. The findings of imaging studies for all dogs who succumbed to radiation necrosis were normal until 3-6 weeks before death. Sequential studies were performed using 0.5 T MRI spin-echo and inversion recovery imaging sequences, and high-resolution (2-3 mm) PET with ${}^{18}{\rm F}$ deoxyglucose and ${}^{82}{\rm Rb}$. The same axial slices (within 1-2 mm) were imaged repeatedly (weekly) after irradiation until death. The earliest CNS changes were seen as decreased metabolic activity in the cortex of the irradiated hemisphere with PET or an increase in signal intensity in the periventricular white matter on $T_{2}\text{-weighted}$ spin-echo imaging on MRI. From the time this increase in signal intensity was first observed, T1 and T2 values increased steadily in both the gray and white matter until death. The changes in white matter were consistently greater than those in gray matter. The results of PET, MRI, and histopathological examinations support the theory that both cellular and vascular mechanisms are involved in radiation necrosis.

Page Thumbnails

  • Thumbnail: Page 
43
    43
  • Thumbnail: Page 
44
    44
  • Thumbnail: Page 
45
    45
  • Thumbnail: Page 
46
    46
  • Thumbnail: Page 
47
    47
  • Thumbnail: Page 
48
    48
  • Thumbnail: Page 
49
    49
  • Thumbnail: Page 
50
    50
  • Thumbnail: Page 
51
    51
  • Thumbnail: Page 
52
    52
  • Thumbnail: Page 
53
    53