TY - JOUR
T1 - Magnetic resonance imaging-based radiation-absorbed dose estimation of
166Ho microspheres in liver radioembolization
AU - Seevinck, PR
AU - Van De Maat, Gerrit H.
AU - De Wit, Tim C.
AU - Vente, Maarten A D
AU - Nijsen, JFW
AU - Bakker, CJG
PY - 2012/7/1
Y1 - 2012/7/1
N2 - Purpose: To investigate the potential of magnetic resonance imaging (MRI) for accurate assessment of the three-dimensional
166Ho activity distribution to estimate radiation-absorbed dose distributions in
166Ho-loaded poly (L-lactic acid) microsphere (
166Ho-PLLA- MS) liver radioembolization. Methods and Materials: MRI, computed tomography (CT), and single photon emission CT (SPECT) experiments were conducted on an anthropomorphic gel phantom with tumor-simulating gel samples and on an excised human tumor-bearing liver, both containing known amounts of
166Ho- PLLA-MS. Three-dimensional radiation-absorbed dose distributions were estimated at the voxel level by convolving the
166Ho activity distribution, derived from quantitative MRI data, with a
166Ho dose point-kernel generated by MCNP (Monte Carlo N-Particle transport code) and from Medical Internal Radiation Dose Pamphlet 17. MRI-based radiation-absorbed dose distributions were qualitatively compared with CT and autoradiography images and quantitatively compared with SPECT-based dose distributions. Both MRI- and SPECT-based activity estimations were validated against dose calibrator measurements. Results: Evaluation on an anthropomorphic phantom showed that MRI enables accurate assessment of local
166Ho-PLLA-MS mass and activity distributions, as supported by a regression coefficient of 1.05 and a correlation coefficient of 0.99, relating local MRI-based mass and activity calculations to reference values obtained with a dose calibrator. Estimated MRI-based radiation-absorbed dose distributions of
166Ho-PLLA-MS in an ex vivo human liver visually showed high correspondence to SPECT-based radiation-absorbed dose distributions. Quantitative analysis revealed that the differences in local and total amounts of
166Ho-PLLA-MS estimated by MRI, SPECT, and the dose calibrator were within 10%. Excellent agreement was observed between MRI- and SPECT-based dose-volume histograms. Conclusions: Quantitative MRI was demonstrated to provide accurate three-dimensional
166Ho-PLLA-MS activity distributions, enabling localized intrahepatic radiation-absorbed dose estimation by convolution with a
166Ho dose point-kernel for liver radioembolization treatment optimization and evaluation.
AB - Purpose: To investigate the potential of magnetic resonance imaging (MRI) for accurate assessment of the three-dimensional
166Ho activity distribution to estimate radiation-absorbed dose distributions in
166Ho-loaded poly (L-lactic acid) microsphere (
166Ho-PLLA- MS) liver radioembolization. Methods and Materials: MRI, computed tomography (CT), and single photon emission CT (SPECT) experiments were conducted on an anthropomorphic gel phantom with tumor-simulating gel samples and on an excised human tumor-bearing liver, both containing known amounts of
166Ho- PLLA-MS. Three-dimensional radiation-absorbed dose distributions were estimated at the voxel level by convolving the
166Ho activity distribution, derived from quantitative MRI data, with a
166Ho dose point-kernel generated by MCNP (Monte Carlo N-Particle transport code) and from Medical Internal Radiation Dose Pamphlet 17. MRI-based radiation-absorbed dose distributions were qualitatively compared with CT and autoradiography images and quantitatively compared with SPECT-based dose distributions. Both MRI- and SPECT-based activity estimations were validated against dose calibrator measurements. Results: Evaluation on an anthropomorphic phantom showed that MRI enables accurate assessment of local
166Ho-PLLA-MS mass and activity distributions, as supported by a regression coefficient of 1.05 and a correlation coefficient of 0.99, relating local MRI-based mass and activity calculations to reference values obtained with a dose calibrator. Estimated MRI-based radiation-absorbed dose distributions of
166Ho-PLLA-MS in an ex vivo human liver visually showed high correspondence to SPECT-based radiation-absorbed dose distributions. Quantitative analysis revealed that the differences in local and total amounts of
166Ho-PLLA-MS estimated by MRI, SPECT, and the dose calibrator were within 10%. Excellent agreement was observed between MRI- and SPECT-based dose-volume histograms. Conclusions: Quantitative MRI was demonstrated to provide accurate three-dimensional
166Ho-PLLA-MS activity distributions, enabling localized intrahepatic radiation-absorbed dose estimation by convolution with a
166Ho dose point-kernel for liver radioembolization treatment optimization and evaluation.
KW - Dosimetry
KW - Holmium microspheres
KW - Magnetic resonance imaging
KW - Radiation-absorbed dose
KW - Radioembolization
UR - http://www.scopus.com/inward/record.url?scp=84861634310&partnerID=8YFLogxK
U2 - 10.1016/j.ijrobp.2011.12.085
DO - 10.1016/j.ijrobp.2011.12.085
M3 - Article
C2 - 22633554
AN - SCOPUS:84861634310
SN - 0360-3016
VL - 83
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
IS - 3
ER -