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1. Validation of vessel size imaging (VSI) in high-grade human gliomas using magnetic resonance imaging, image-guided biopsies, and quantitative immunohistochemistry.

Author

Chakhoyan, Ararat, Yao, Jingwen, Leu, Kevin, Pope, Whitney B, Salamon, Noriko, Yong, William, Lai, Albert, Nghiemphu, Phioanh L, Everson, Richard G, Prins, Robert M, Liau, Linda M, Nathanson, David A, Cloughesy, Timothy F, and Ellingson, Benjamin M

Subjects
Blood Vessels, Humans, Glioma, Brain Neoplasms, Magnetic Resonance Imaging, Immunohistochemistry, Reproducibility of Results, Blood Volume, Middle Aged, Female, Male, Neoplasm Grading, Image-Guided Biopsy, Brain Disorders, Neurosciences, Brain Cancer, Clinical Research, Biomedical Imaging, Rare Diseases, Cancer, 4.2 Evaluation of markers and technologies, Cardiovascular
Abstract

To evaluate the association between a vessel size index (VSIMRI) derived from dynamic susceptibility contrast (DSC) perfusion imaging using a custom spin-and-gradient echo echoplanar imaging (SAGE-EPI) sequence and quantitative estimates of vessel morphometry based on immunohistochemistry from image-guided biopsy samples. The current study evaluated both relative cerebral blood volume (rCBV) and VSIMRI in eleven patients with high-grade glioma (7 WHO grade III and 4 WHO grade IV). Following 26 MRI-guided glioma biopsies in these 11 patients, we evaluated tissue morphometry, including vessel density and average radius, using an automated procedure based on the endothelial cell marker CD31 to highlight tumor vasculature. Measures of rCBV and VSIMRI were then compared to histological measures. We demonstrate good agreement between VSI measured by MRI and histology; VSIMRI = 13.67 μm and VSIHistology = 12.60 μm, with slight overestimation of VSIMRI in grade III patients compared to histology. rCBV showed a moderate but significant correlation with vessel density (r = 0.42, p = 0.03), and a correlation was also observed between VSIMRI and VSIHistology (r = 0.49, p = 0.01). The current study supports the hypothesis that vessel size measures using MRI accurately reflect vessel caliber within high-grade gliomas, while traditional measures of rCBV are correlated with vessel density and not vessel caliber.

Published
2019

2. FMISO-PET-derived brain oxygen tension maps: application to glioblastoma and less aggressive gliomas

Author

Chakhoyan, Ararat, Guillamo, Jean-Sébastien, Collet, Solène, Kauffmann, François, Delcroix, Nicolas, Lechapt-Zalcman, Emmanuèle, Constans, Jean-Marc, Petit, Edwige, MacKenzie, Eric, Barre, Louisa, Bernaudin, Myriam, Touzani, Omar, Valable, Samuel, Hypoxie, physiopathologies cérébrovasculaire et tumorale (CERVOxy), Imagerie et Stratégies Thérapeutiques des pathologies Cérébrales et Tumorales (ISTCT), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN), Laboratoire de Mathématiques Nicolas Oresme (LMNO), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Unité Support CYCERON, Normandie Université (NU)-Normandie Université (NU)-CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Tumorothèque de Caen Basse-Normandie (TCBN)-Centre National de la Recherche Scientifique (CNRS), Service de Radiologie [CHU Caen], Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Tumorothèque de Caen Basse-Normandie (TCBN), Laboratoire de Développements Méthodologiques en Tomographie par Emission de Positons (LDM-TEP), Service Hospitalier Frédéric Joliot (SHFJ), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Imagerie et Stratégies Thérapeutiques des pathologies Cérébrales et Tumorales (ISTCT), Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Imagerie et Stratégies Thérapeutiques des pathologies Cérébrales et Tumorales (ISTCT)

Subjects
Adult, Male, Brain Mapping, Brain Neoplasms, [SCCO.NEUR]Cognitive science/Neuroscience, Perfusion Imaging, lcsh:R, lcsh:Medicine, Middle Aged, White Matter, Article, ROC Curve, Positron Emission Tomography Computed Tomography, Humans, Female, lcsh:Q, Prospective Studies, Gray Matter, Misonidazole, Glioblastoma, Hypoxia, Brain, lcsh:Science, Aged
Abstract

Quantitative imaging modalities for the analysis of hypoxia in brain tumors are lacking. The objective of this study was to generate absolute maps of tissue ptO2 from [18F]-FMISO images in glioblastoma and less aggressive glioma patients in order to quantitatively assess tumor hypoxia. An ancillary objective was to compare estimated ptO2 values to other biomarkers: perfusion weighted imaging (PWI) and tumor metabolism obtained from 1H-MR mono-voxel spectroscopy (MRS). Ten patients with glioblastoma (GBM) and three patients with less aggressive glioma (nGBM) were enrolled. All patients had [18F]-FMISO and multiparametric MRI (anatomic, PWI, MRS) scans. A non-linear regression was performed to generate ptO2 maps based on normal appearing gray (NAGM) and white matter (NAWM) for each patient. As expected, a marked [18F]-FMISO uptake was observed in GBM patients. The ptO2 based on patient specific calculations was notably low in this group (4.8 ± 1.9 mmHg, p

Published
2017
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3. Validation of vessel size imaging (VSI) in high-grade human gliomas using magnetic resonance imaging, image-guided biopsies, and quantitative immunohistochemistry

Author

Ararat Chakhoyan, Jingwen Yao, Kevin Leu, Benjamin M. Ellingson, William H. Yong, Richard Everson, David Nathanson, Noriko Salamon, Timothy F. Cloughesy, Albert Lai, Robert M. Prins, Whitney B. Pope, Phioanh L. Nghiemphu, and Linda M. Liau

Subjects
0301 basic medicine, CD31, Image-Guided Biopsy, Male, lcsh:Medicine, Perfusion scanning, Cardiovascular, Article, 03 medical and health sciences, 0302 clinical medicine, Rare Diseases, Clinical Research, Glioma, Biopsy, Medicine, Humans, lcsh:Science, Cancer, screening and diagnosis, Multidisciplinary, Blood Volume, medicine.diagnostic_test, business.industry, Brain Neoplasms, lcsh:R, Neurosciences, Reproducibility of Results, Magnetic resonance imaging, Histology, Middle Aged, medicine.disease, Immunohistochemistry, Magnetic Resonance Imaging, Brain Disorders, Vessel diameter, Brain Cancer, Detection, 030104 developmental biology, Biomedical Imaging, Blood Vessels, lcsh:Q, Female, Neoplasm Grading, business, Nuclear medicine, 030217 neurology & neurosurgery, 4.2 Evaluation of markers and technologies
Abstract

To evaluate the association between a vessel size index (VSIMRI) derived from dynamic susceptibility contrast (DSC) perfusion imaging using a custom spin-and-gradient echo echoplanar imaging (SAGE-EPI) sequence and quantitative estimates of vessel morphometry based on immunohistochemistry from image-guided biopsy samples. The current study evaluated both relative cerebral blood volume (rCBV) and VSIMRI in eleven patients with high-grade glioma (7 WHO grade III and 4 WHO grade IV). Following 26 MRI-guided glioma biopsies in these 11 patients, we evaluated tissue morphometry, including vessel density and average radius, using an automated procedure based on the endothelial cell marker CD31 to highlight tumor vasculature. Measures of rCBV and VSIMRI were then compared to histological measures. We demonstrate good agreement between VSI measured by MRI and histology; VSIMRI = 13.67 μm and VSIHistology = 12.60 μm, with slight overestimation of VSIMRI in grade III patients compared to histology. rCBV showed a moderate but significant correlation with vessel density (r = 0.42, p = 0.03), and a correlation was also observed between VSIMRI and VSIHistology (r = 0.49, p = 0.01). The current study supports the hypothesis that vessel size measures using MRI accurately reflect vessel caliber within high-grade gliomas, while traditional measures of rCBV are correlated with vessel density and not vessel caliber.

Published
2019

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