PURPOSE: To identify radiation-induced changes in the cerebral vasculature of healthy tissue in the first four months following radiotherapy through the analysis of dynamic-susceptibility contrast perfusion imaging. MATERIALS AND METHODS: Dynamic gradient-echo imaging was performed on 22 patients during injection of a bolus of Gd-DTPA contrast. The relative cerebral blood volume (rCBV), maximum DeltaR2* of the first passage of the bolus, and a recirculation parameter were derived from gamma-variate fits of the dynamic data. The white matter (WM) rCBV and peak heights were estimated through correlation with segmented T1-weighted images. A percent recovery to baseline was also computed to further describe the recirculation phase. RESULTS: A significant elevation of the recirculation phase was observed at doses>15 Gy at two months following radiotherapy. This was reflected in an increased recirculation parameter in the fitted curves in the 15-30, 30-45, and >45 Gy dose groups to 2.8%, 3.8%, and 2.4% above the <15 Gy voxels, as well as in a decline in percent recovery to baseline. A trend toward lower rCBV and peak heights was observed at that same time point. CONCLUSION: The observed results suggest a dose-dependent decline in vessel density and increase in vascular permeability and/or tortuosity in irradiated normal-appearing brain tissue at two months following radiotherapy. Copyright (c) 2005 Wiley-Liss, Inc.
PURPOSE: To identify radiation-induced changes in the cerebral vasculature of healthy tissue in the first four months following radiotherapy through the analysis of dynamic-susceptibility contrast perfusion imaging. MATERIALS AND METHODS: Dynamic gradient-echo imaging was performed on 22 patients during injection of a bolus of Gd-DTPA contrast. The relative cerebral blood volume (rCBV), maximum DeltaR2* of the first passage of the bolus, and a recirculation parameter were derived from gamma-variate fits of the dynamic data. The white matter (WM) rCBV and peak heights were estimated through correlation with segmented T1-weighted images. A percent recovery to baseline was also computed to further describe the recirculation phase. RESULTS: A significant elevation of the recirculation phase was observed at doses>15 Gy at two months following radiotherapy. This was reflected in an increased recirculation parameter in the fitted curves in the 15-30, 30-45, and >45 Gy dose groups to 2.8%, 3.8%, and 2.4% above the <15 Gy voxels, as well as in a decline in percent recovery to baseline. A trend toward lower rCBV and peak heights was observed at that same time point. CONCLUSION: The observed results suggest a dose-dependent decline in vessel density and increase in vascular permeability and/or tortuosity in irradiated normal-appearing brain tissue at two months following radiotherapy. Copyright (c) 2005 Wiley-Liss, Inc.
Authors: Janine M Lupo; Cynthia F Chuang; Susan M Chang; Igor J Barani; Bert Jimenez; Christopher P Hess; Sarah J Nelson Journal: Int J Radiat Oncol Biol Phys Date: 2011-10-12 Impact factor: 7.038
Authors: Suja Saraswathy; Forrest W Crawford; Kathleen R Lamborn; Andrea Pirzkall; Susan Chang; Soonmee Cha; Sarah J Nelson Journal: J Neurooncol Date: 2008-09-23 Impact factor: 4.130
Authors: Friso W A Hoefnagels; Frank J Lagerwaard; Esther Sanchez; Cornelis J A Haasbeek; Dirk L Knol; Ben J Slotman; W Peter Vandertop Journal: J Neurol Date: 2009-03-10 Impact factor: 4.849