Usefulness of Double Dose Contrast-enhanced Magnetic Resonance Imaging for Clear Delineation of Gross Tumor Volume in Stereotactic Radiotherapy Treatment Planning of Metastatic Brain Tumors: A Dose Comparison Study

Subedi, Kalloo Sharma

doi:10.1016/j.prro.2013.01.113

Cited by 2 publications

(2 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5). This is in line with several studies demonstrating a higher sensitivity for detecting small metastases using double or triple doses of GBCA 43–46 . Similar contrast (tumor-to-brain) was observed for gadoquatrane at a less than 75% of the Gd dose (more than 90% less for molecule dose) compared with the standard dose of gadoterate meglumine (0.1 mmol Gd/kg bw) (Fig.…”

Section: Discussionsupporting

confidence: 91%

Preclinical Profile of Gadoquatrane

Lohrke¹,

Berger

Frenzel³

et al. 2022

Invest Radiol

View full text Add to dashboard Cite

Objectives The aim of this report was to characterize the key physicochemical, pharmacokinetic (PK), and magnetic resonance imaging (MRI) properties of gadoquatrane (BAY 1747846), a newly designed tetrameric, macrocyclic, extracellular gadolinium-based contrast agent (GBCA) with high relaxivity and stability. Materials and Methods The r1-relaxivities of the tetrameric gadoquatrane at 1.41 and 3.0 T were determined in human plasma and the nuclear magnetic relaxation dispersion profiles in water and plasma. The complex stability was analyzed in human serum over 21 days at pH 7.4 at 37°C and was compared with the linear GBCA gadodiamide and the macrocyclic GBCA (mGBCA) gadobutrol. In addition, zinc transmetallation assay was performed to investigate the kinetic inertness. Protein binding and the blood-to-plasma ratio were determined in vitro using rat and human plasma. The PK profile was evaluated in rats (up to 7 days postinjection). Magnetic resonance imaging properties were investigated using a glioblastoma (GS9L) rat model. Results The new chemical entity gadoquatrane is a macrocyclic tetrameric Gd complex with one inner sphere water molecule per Gd ( q = 1). Gadoquatrane showed high solubility in buffer (1.43 mol Gd/L, 10 mM Tris-HCl, pH 7.4), high hydrophilicity (logP −4.32 in 1-butanol/water), and negligible protein binding. The r1-relaxivity of gadoquatrane in human plasma per Gd of 11.8 mM −1 ·s −1 (corresponding to 47.2 mM −1 ·s −1 per molecule at 1.41 T at 37°C, pH 7.4) was more than 2-fold (8-fold per molecule) higher compared with established mGBCAs. Nuclear magnetic relaxation dispersion profiles confirmed the more than 2-fold higher r1-relaxivity in human plasma for the clinically relevant magnetic field strengths from 0.47 to 3.0 T. The complex stability of gadoquatrane at physiological conditions was very high. The observed Gd release after 21 days at 37°C in human serum was below the lower limit of quantification. Gadoquatrane showed no Gd 3+ release in the presence of zinc in the transmetallation assay. The PK profile (plasma elimination, biodistribution, recovery) was comparable to that of gadobutrol. In MRI, the quantitative evaluation of the tumor-to-brain contrast in the rat glioblastoma model showed significantly improved contrast enhancement using gadoquatrane compared with gadobutrol at the same Gd dose administered (0.1 mmol Gd/kg body weight). In comparison to gadoterate meglumine, similar contrast enhancement was reached with gadoquatrane with 75% less Gd dose. In terms of the molecule dose, this was reduced by 90% when compared with gadoterate meglumine. Because of its tetrameric structure and hence lower number of molecules per volume, all prepared formulations of gadoquatrane were iso-osmolar to blood. Conclusions The tetrameric...

show abstract

Section: Discussionsupporting

confidence: 91%

Preclinical Profile of Gadoquatrane

Lohrke¹,

Berger

Frenzel³

et al. 2022

Invest Radiol

View full text Add to dashboard Cite

show abstract

“…Special imaging techniques have been proposed to improve this process. For instance, double‐dose Gd‐based contrast‐enhanced thin‐slice MRI produced more precise delineation of lesions compared with using a single dose . The addition of overlapping CUBE maximum intensity projection (MIP) images, which have a better contrast‐to‐noise ratio of metastatic lesions than post‐Gd 3D isometric high‐resolution sequences, are often used to enhance the sensitivity of detection.…”

Section: Discussionmentioning

confidence: 99%

Deep learning enables automatic detection and segmentation of brain metastases on multisequence MRI

Grøvik

Michael

et al. 2019

Magnetic Resonance Imaging

195

168

View full text Add to dashboard Cite

Background: Detecting and segmenting brain metastases is a tedious and time-consuming task for many radiologists, particularly with the growing use of multisequence 3D imaging. Purpose: To demonstrate automated detection and segmentation of brain metastases on multisequence MRI using a deep-learning approach based on a fully convolution neural network (CNN). Study Type: Retrospective. Population: In all, 156 patients with brain metastases from several primary cancers were included. Field Strength: 1.5T and 3T. [Correction added on May 24, 2019, after first online publication: In the preceding sentence, the first field strength listed was corrected.] Sequence: Pretherapy MR images included pre-and postgadolinium T 1 -weighted 3D fast spin echo (CUBE), postgadolinium T 1 -weighted 3D axial IR-prepped FSPGR (BRAVO), and 3D CUBE fluid attenuated inversion recovery (FLAIR). Assessment: The ground truth was established by manual delineation by two experienced neuroradiologists. CNN training/development was performed using 100 and 5 patients, respectively, with a 2.5D network based on a GoogLeNet architecture. The results were evaluated in 51 patients, equally separated into those with few (1-3), multiple (4-10), and many (>10) lesions. Statistical Tests: Network performance was evaluated using precision, recall, Dice/F1 score, and receiver operating characteristic (ROC) curve statistics. For an optimal probability threshold, detection and segmentation performance was assessed on a per-metastasis basis. The Wilcoxon rank sum test was used to test the differences between patient subgroups. Results: The area under the ROC curve (AUC), averaged across all patients, was 0.98 AE 0.04. The AUC in the subgroups was 0.99 AE 0.01, 0.97 AE 0.05, and 0.97 AE 0.03 for patients having 1-3, 4-10, and >10 metastases, respectively. Using an average optimal probability threshold determined by the development set, precision, recall, and Dice score were 0.79 AE 0.20, 0.53 AE 0.22, and 0.79 AE 0.12, respectively. At the same probability threshold, the network showed an average falsepositive rate of 8.3/patient (no lesion-size limit) and 3.4/patient (10 mm 3 lesion size limit). Data Conclusion: A deep-learning approach using multisequence MRI can automatically detect and segment brain metastases with high accuracy. Level of Evidence: 3 Technical Efficacy Stage: 2 View this article online at wileyonlinelibrary.com.

show abstract

Usefulness of Double Dose Contrast-enhanced Magnetic Resonance Imaging for Clear Delineation of Gross Tumor Volume in Stereotactic Radiotherapy Treatment Planning of Metastatic Brain Tumors: A Dose Comparison Study

Cited by 2 publications

References 15 publications

Preclinical Profile of Gadoquatrane

Preclinical Profile of Gadoquatrane

Deep learning enables automatic detection and segmentation of brain metastases on multisequence MRI

Contact Info

Product

Resources

About