Convection-Enhanced Delivery of an Iodine Tracer Into Rat Brain for Synchrotron Stereotactic Radiotherapy

Journal Article · Sun Jul 01 00:00:00 EDT 2007 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2007.01.065· OSTI ID:20951726

Rousseau, Julia ^[1]; Boudou, Caroline ^[1]; Esteve, Francois ^[1]; Elleaume, Helene ^[2]

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1. INSERM U647, Grenoble (France)
2. INSERM U647, Grenoble (France) and Universite Joseph Fourier, Grenoble (France) and European Synchrotron Radiation Facility, Medical Beamline ID17, Grenoble (France) and Centre Hospitalier Universitaire, Hopital Michallon, Grenoble (France)

Purpose: To evaluate direct intracerebral and intratumoral iodine delivery as means to improve iodine distribution for synchrotron stereotactic radiotherapy (SSR) and to evaluate the corresponding X-ray dose distribution. Methods and Materials: Healthy rats and F98 glioma-bearing rats received an iodinated contrast agent (iopamidol) intracerebrally either by bolus injection (5 {mu}L over approximately 1 min) or by convection-enhanced delivery (infusion volumes of 5, 10, and 20 {mu}L at a rate of 0.5 {mu}L/min). We used synchrotron computed tomography (CT) to determine the iodine distribution after completion of infusion and a Monte Carlo code to compute the resulting radiation dose in SSR. Results: Post-infusion CT imaging revealed high iodine concentrations in the perfused area with both injection methods. The iodine concentration remained elevated, with an exponential decay time constant of approximately 50 min, well suited for SSR treatment. Convection-enhanced delivery was shown to provide more uniform and controlled volumes of distribution than bolus injection and was chosen to evaluate the corresponding X-ray dose distribution. Sharp dose gradients around the target and excellent sparing of the contralateral brain were achievable with low iodine concentrations in the surrounding healthy brain tissues and blood vessels. Conclusions: Convection-enhanced delivery is an effective method to deliver high iodine concentrations and could improve the outcome of iodine-enhanced SSR.

• OSTI ID: 20951726
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 3 Vol. 68; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BLOOD VESSELS
BRAIN
COMPUTERIZED TOMOGRAPHY
DOSIMETRY
GLIOMAS
INFUSION
IODINE
IOPAMIDOL
MONTE CARLO METHOD
RADIATION DOSE DISTRIBUTIONS
RADIATION DOSES
RADIOTHERAPY
RATS
SYNCHROTRONS