Double-blind, efficacy evaluation of gadobenate dimeglumine, a gadolinium chelate with enhanced relaxivity, in malignant lesions of the brain

Gadolinium contrast agents for CNS imaging: current concepts and clinical evidence

SUMMARY

The aim of this article was to review the properties of the various gadolinium-based contrast agents used for CNS imaging along with the clinical evidence and published data that highlight the impact these different properties can have on diagnostic performance. In addition, approaches to optimizing image acquisition that take into account the different properties of specific gadolinium-based contrast agents and an extensive review of the safety profiles of the various agents are presented.

Decreased incidence of NSF in patients on dialysis after changing gadolinium contrast-enhanced MRI protocols

PURPOSE

To retrospectively determine the incidence of nephrogenic systemic fibrosis (NSF) in patients on dialysis administered either a lower dose high-relaxivity linear gadolinium-chelate, gadobenate dimeglumine (MultiHance, MH), compared to a standard dose linear gadolinium chelate, gadodiamide (Omniscan, OM).

MATERIALS AND METHODS

This study was Health Insurance Portability and Accountability Act (HIPAA)-compliant and Institutional Review Board (IRB)-approved. As per institution standardized contrast-enhanced magnetic resonance imaging (MRI) protocols, patients on dialysis were imaged using either MH, between 2/2007 to 9/2008, or OM between 10/2003 and 1/2007. Rates of NSF were compared using 95% score-based confidence intervals (CI). The Wilcoxon rank sum test was used to test similarity/difference between contrast doses given to each patient group.

RESULTS

Overall, 312 patients on dialysis received OM and eight (2.6%) developed NSF (95% CI: 1.30%-4.98%). In all, 784 patients on dialysis received MH at a mean cumulative dose of 0.11 mmol/kg (0.05-0.75 mmol/kg) and no cases of NSF were identified (upper 95% confidence bound of 0.45%). The mean cumulative dose of OM was 0.16 mmol/kg (0.1-0.9 mmol/kg) for all patients and 0.28 mmol/kg (0.1-0.8 mmol/kg) for the patients with NSF. The median OM dose was greater in patients who developed NSF (P = 0.03), and was greater than the median MH dose (P < 0.005).

CONCLUSION

NSF incidence in at-risk patients receiving contrast-enhanced MRI can be reduced after changing contrast administration protocols that includes changing the type and dose of contrast agent.

Dynamic contrast enhancement of experimental glioma an intra-individual comparative study to assess the optimal time delay

RATIONALE AND OBJECTIVES

The aim of this study was to compare tumor signal and contrast media uptake characteristics on contrast-enhanced T1-weighted sequences at 3 Tesla over 30 minutes after double-dose administration of different contrast agents in an animal model of brain glioma.

MATERIALS AND METHODS

Nine rats underwent magnetic resonance imaging (MRI) after stereotactic F98 glioma cell implantation before and repetitively for 30 minutes after injection of gadobutrol, gadopentetate, and gadobenate, respectively. Signal-to-noise ratio (SNR) and tumor contrast-to-noise ratio (CNR) were evaluated and MRI-derived tumor volumes were compared to histology.

RESULTS

Postcontrast tumor SNR and CNR peaked at 4 minutes after contrast application. While contrast-enhancement within the tumor was fading, tumor volume increased by continuous contrast-uptake of peripheral parts between 4 minutes (137 + or - 29 mm(3), 126 + or - 16 mm(3), 141 + or - 24 mm(3)) and 20 minutes (182 + or - 35 mm(3), 164 + or - 32 mm(3), 191 + or - 25 mm(3)), respectively. At 8 and 12 minutes, 84% and 91% of the tumor volume were definable, respectively.

CONCLUSION

Optimal correlation between MRI-derived tumor volume and histology is achieved by imaging up to 20 minutes after contrast application. At 4 minutes (this delay is mostly used in clinical routine), only 75% of the enhancing tumor volume is assessable. A delay of 8 minutes already reveals 84% of the tumor and seems to be a practical clinical compromise.

Comparison of gadobenate dimeglumine and gadodiamide in the evaluation of spinal vascular anatomy with MR angiography

BACKGROUND AND PURPOSE

Spinal MRA has been increasingly used to evaluate non-invasively the spinal cord vasculature. Our aim was to prospectively compare gadobenate dimeglumine with gadodiamide in the assessment of the normal spinal cord vasculature by using contrast-enhanced MRA, with the hypothesis that high T1 relaxivity gadolinium compounds may improve visualization of the intradural vessels.

MATERIALS AND METHODS

Twenty subjects underwent 2 temporally separated contrast-enhanced spinal MRAs with gadobenate dimeglumine and gadodiamide (0.2 mmol/kg). Two blinded observers rated postprocessed images on the following qualitative parameters: background homogeneity, sharpness, vascular continuity, and contrast enhancement. Delineation of the ASA, AKA, hairpin configuration of the ASA-AKA connection, and visualized ASA length were recorded. Each observer indicated which of the 2 matched studies he or she thought was of the best overall diagnostic quality.

RESULTS

According to both observers gadobenate dimeglumine was superior to gadodiamide in the representation of vascular continuity and contrast (P value < .05). Background homogeneity was not significantly different between the studies. One observer favored gadobenate dimeglumine over gadodiamide in the demonstration of vascular sharpness, while the second observer did not find any significant difference between contrast agents. There was no significant difference between contrast agents in the visualization of the ASA, AKA, hairpin-shaped ASA-AKA connection, and visualized length of the ASA. The overall quality of the gadobenate dimeglumine-enhanced MRA was deemed superior in 15 and 16 cases, respectively, by the 2 observers.

CONCLUSIONS

Improved image quality and vascular contrast enhancement of spinal MRA at 1.5T is achieved with high T1 relaxivity gadolinium contrast agents compared with conventional agents at equivalent doses.

Contrast-enhanced MR imaging of brain lesions: a large-scale intraindividual crossover comparison of gadobenate dimeglumine versus gadodiamide

BACKGROUND AND PURPOSE

The higher relaxivity of gadobenate dimeglumine compared with gadodiamide is potentially advantageous for contrast-enhanced brain MR imaging. This study intraindividually compared 0.1-mmol/kg doses of these agents for qualitative and quantitative lesion enhancement.

MATERIALS AND METHODS

Adult patients with suggested or known brain lesions underwent 2 identical MR imaging examinations at 1.5T, one with gadobenate dimeglumine and the other with gadodiamide. The agents were administered in randomized order separated by 3-14 days. Imaging sequences and postinjection acquisition timing were identical for the 2 examinations. Three blinded readers evaluated images qualitatively for diagnostic information (lesion extent, delineation, morphology, enhancement, and global preference) and quantitatively for contrast-to-noise ratio (CNR).

RESULTS

One hundred thirteen of 138 enrolled patients successfully underwent both examinations. Final diagnoses were intra-axial tumor, metastasis, extra-axial tumor, or other (47, 27, 18, and 21 subjects, respectively). Readers 1, 2, and 3 demonstrated global preference for gadobenate dimeglumine in 63 (55.8%), 77 (68.1%), and 73 (64.6%) patients, respectively, compared with 3, 2, and 3 patients for gadodiamide (P < .0001, all readers). Highly significant (P < .0001, all readers) preference for gadobenate dimeglumine was demonstrated for all qualitative end points and for CNR (increases of 23.3%-34.7% and 42.4%-48.9% [spin-echo and gradient-refocused echo sequences, respectively] for gadobenate dimeglumine compared with gadodiamide). Inter-reader agreement was good for all evaluations (kappa = 0.47-0.69). Significant preference for gadobenate dimeglumine was demonstrated for all lesion subgroup analyses.

CONCLUSION

Significantly greater diagnostic information and lesion enhancement are achieved on brain MR imaging with 0.1-mmol/kg gadobenate dimeglumine compared with gadodiamide at an equivalent dose.

Extracellular gadolinium-based contrast media: differences in diagnostic efficacy

Since the introduction of the first gadolinium-based contrast agent (Gd-CA) in 1988 it has become clear that these agents significantly improve the diagnostic efficacy of MRI. Studies on single agents have shown that, in comparison to unenhanced sequences, all agents help to improve the detection and delineation of lesions which can alter diagnosis in up to 40% of patients. Doubling or tripling the standard dose of 0.1 mmol/kg body weight may be beneficial for selected indications (e.g. brain perfusion, equivocal single dose study in MRI for brain metastasis, small vessel MR angiography). A more limited number of studies have compared the various agents. These studies do not show clinically significant differences in diagnostic efficacy between the various extracellular Gd-CA. Agents with higher concentration or protein binding may be relatively better suitable for selected applications (e.g. perfusion MRI). The higher relaxivity agents may be used in somewhat lower doses than the extracellular agents.

Improving lesion detection and visualization: implications for neurosurgical planning and follow-up

Contrast-enhanced magnetic resonance (MR) imaging is considered the most sensitive method for detecting tumors in the central nervous system (CNS). The primary objective is to improve lesion detection, delineation, and characterization (benign or malignant) in order to more accurately define the location, extent, and type of disease and the appropriate treatment option for improved patient outcome (surgical intervention, radiation therapy or cytotoxic chemotherapy). This article reviews the various types of tumor occurring in the brain and the specific role of contrast-enhanced MR imaging for the evaluation of these tumors. Emphasis is placed on the value of contrast-enhanced MR imaging in the evaluation of primary intra-axial brain lesions and how high relaxivity contrast agents such as MultiHance (Bracco Imaging, Milan, Italy) might improve detection, treatment planning, and follow-up.

Contrast Enhancement of Central Nervous System Lesions: Multicenter Intraindividual Crossover Comparative Study of Two MR Contrast Agents

PURPOSE

To prospectively compare gadobenate dimeglumine with gadopentetate dimeglumine (0.1 mmol per kilogram body weight) for enhanced magnetic resonance (MR) imaging of central nervous system (CNS) lesions.

MATERIALS AND METHODS

This study was HIPAA-compliant at U.S. centers and was conducted at all centers according to the Good Clinical Practice standard. Institutional review board and regulatory approval were granted; written informed consent was obtained. Seventy-nine men and 78 women (mean age, 50.5 years +/- 14.4 [standard deviation]) were randomized to group A (n = 78) or B (n = 79). Patients underwent two temporally separated 1.5-T MR imaging examinations. In randomized order, gadobenate followed by gadopentetate was administered in group A; order of administration was reversed in group B. Contrast agent administration (volume, speed of injection), imaging parameters before and after injection, and time between injections and postinjection acquisitions were identical for both examinations. Three blinded neuroradiologists evaluated images by using objective image interpretation criteria for diagnostic information end points (lesion border delineation, definition of disease extent, visualization of internal morphologic features of the lesion, enhancement of the lesion) and quantitative parameters (percentage of lesion enhancement, contrast-to-noise ratio [CNR]). Overall diagnostic preference in terms of lesion conspicuity, detectability, and diagnostic confidence was assessed. Between-group comparisons were performed with Wilcoxon signed rank test.

RESULTS

Readers 1, 2, and 3 demonstrated overall preference for gadobenate in 75, 89, and 103 patients, compared with that for gadopentetate in seven, 10, and six patients, respectively (P < .0001). Significant (P < .0001) preference for gadobenate was demonstrated for diagnostic information end points, percentage of lesion enhancement, and CNR. Superiority of gadobenate was significant (P < .001) in patients with intraaxial and extraaxial lesions.

CONCLUSION

Gadobenate compared with gadopentetate at an equivalent dose provides significantly better enhancement and diagnostic information for CNS MR imaging.

Contrast-enhanced, high-resolution, susceptibility-weighted magnetic resonance imaging of the brain: dose-dependent optimization at 3 tesla and 1.5 tesla in healthy volunteers

OBJECTIVES

We sought to determine the optimal dose of a contrast agent with known high relaxivity on 1.5 and 3 Tesla scanners that would achieve the best compromise between image quality and scan time for the clinical application of contrast-enhanced susceptibility-weighted imaging (CE-SWI).

METHODS

Pre- and postcontrast SWI was performed with different contrast agent doses (0.05, 0.1, and 0.2 mmol/kg gadobenate dimeglumine) at both 1.5 and 3 T in 6 healthy volunteers, resulting in 72 examinations. Venograms were created from minimum intensity projection reconstructions over specified deep white matter volumes to enhance the visual appearance of connected venous structures. Three independent radiologists blindly rated the visibility of the veins on a continuous scale of 1 to 10. A general linear model was used for statistical evaluation, with fixed effects of the contrast agent dose, the field strength, the rater and the patients as a random effect.

RESULTS

With CE-SWI, we found significant differences in the visibility of the deep veins dependent on the contrast media dose (P=0.02). At 3 T, the visibility of deep venous vessels, with regard to susceptibility effect, image quality, and scan time reduction after a standard contrast agent dose 0.1 mmol/kg was significantly better than that achieved with 0.05 mmol/kg. The visibility was considered equal with 0.1 mmol/kg of the contrast agent to the precontrast images and a dose of 0.2 mmol/kg. At 1.5 T, no significant difference was found between the 4 contrast agent doses. We found no difference in the visibility of the veins with the shorter sequences at 3 T compared with the sequences at 1.5 T.

CONCLUSIONS

Only a standard dose (0.1 mmol/kg) of gadobenate dimeglumine is required to achieve the optimum susceptibility effect and image quality at 3 T, together with a reduced scan time. This result can be attributed to the higher relaxivity of gadobenate dimeglumine, compared with conventional gadolinium chelates.

The Efficacy of Gadobenate Dimeglumine (Gd-BOPTA) at 3 Tesla in Brain Magnetic Resonance Imaging

OBJECTIVES

The objectives of this study were to analyze the differences in contrast enhancement using gadobenate dimeglumine (Gd-BOPTA or MultiHance) at 3 T versus 1.5 T and to compare Gd-BOPTA with a standard gadolinium chelate, gadopentetate dimeglumine (Gd-DTPA or Magnevist), at 3 T in a rat glioma model.

MATERIALS AND METHODS

Twelve rats with surgically implanted gliomas were randomized to either comparing Gd-BOPTA at 1.5 T versus 3 T (n=7) or comparing Gd-BOPTA and Gd-DTPA at 3 T (n=5). Matched T1-weighted spin-echo techniques were used for both comparisons and the order of examinations was randomized. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and lesion enhancement (LE) were evaluated using a region-of-interest analysis. A veterinary histopathologist evaluated all brain specimens.

RESULTS

In the evaluation of Gd-BOPTA at 3 T and 1.5 T, there were significant increases in SNR, LE, and CNR at 3 T. Average increases in brain and tumor SNR were 93% (P<0.0001) and 92% (P<0.0001), respectively. CNR increased by 121% (P<0.0001). Comparison of Gd-BOPTA and Gd-DTPA at 3 T demonstrated significantly higher CNR and LE with Gd-BOPTA. CNR increased by 35% (P=0.002). LE increased by 44% (P=0.03).

CONCLUSIONS

Gd-BOPTA provides significantly higher CNR at 3 T compared with 1.5 T and also demonstrates significantly higher CNR when compared with a standard Gd-chelate at 3 T. As a result of transient protein binding, Gd-BOPTA may be superior to standard gadolinium chelates in neurologic imaging at 3 T.

Comparison of gadobenate dimeglumine (Gd-BOPTA) with gadopentetate dimeglumine (Gd-DTPA) for enhanced MR imaging of brain and spine tumours in children

BACKGROUND

Gadobenate dimeglumine (Gd-BOPTA) demonstrates superior enhancement of brain tumours in adult patients than Gd-DTPA.

OBJECTIVE

To determine whether Gd-BOPTA has advantages over Gd-DTPA for enhanced MR imaging of paediatric brain and spine tumours.

MATERIALS AND METHODS

Sixty-three subjects, aged 6 months to 16 years, who were enrolled in a prospective, fully blinded, randomized parallel-group phase III clinical trial, received 0.1 mmol/kg doses of either Gd-BOPTA (n=29) or Gd-DTPA (n=34). The MR images were acquired before and within 10 min of contrast agent injection. The primary objective was to compare the difference from pre-dose to post-dose lesion visualization between Gd-BOPTA and Gd-DTPA. Lesion visualization was determined as the sum of individual scores for three criteria of lesion morphological characteristics (lesion border delineation, internal morphology, and contrast enhancement), each assessed qualitatively using 4-point scales. Quantitative evaluation compared changes in lesion-to-background (LBR) and contrast-to-noise (CNR) ratios and per cent enhancement. Monitoring for adverse events and evaluation of vital signs and laboratory values was performed.

RESULTS

Pre-dose to post-dose changes in lesion visualization were significantly better for Gd-BOPTA for both lesion level (2.68+/-2.17 vs. 1.05+/-1.90, P=0.0106) and patient level (2.55+/-2.18 vs. 1.14+/-1.68, P=0.0079) comparisons. The mean pre-dose to post-dose change in CNR was greater for Gd-BOPTA (9.13+/-15.36) than Gd-DTPA (2.18+/-9.90), but the difference was only marginally significant (P=0.0779; 95% CI: -0.553, 14.454) because of wide variations of signal intensity between lesions. Similar findings were obtained for LBR and per cent enhancement. No differences between the agents were noted in terms of safety parameters.

CONCLUSIONS

At an equivalent dose Gd-BOPTA is significantly better than Gd-DTPA for visualization of enhancing CNS tumours in paediatric patients.

Gadobenate dimeglumine (MultiHance) in MR imaging of the CNS: studies to assess the benefits of a high relaxivity contrast agent

The use of Gd-BOPTA as a contrast agent for morphological and functional MR imaging allows improved detection and delineation of CNS lesions compared to conventional gadolinium agents. This results not only to more confident diagnosis, but also to a substantially improved differential diagnosis process. The higher relaxivity of Gd-BOPTA also helps to optimize functional MR imaging studies e.g. perfusion MRI and dynamic MR angiographic protocols.

Primary and Secondary Brain Tumors at MR Imaging: Bicentric Intraindividual Crossover Comparison of Gadobenate Dimeglumine and Gadopentetate Dimeglumine

PURPOSE

To evaluate the safety of and compare the enhancement characteristics of gadobenate dimeglumine (MultiHance; Bracco Imaging, Milan, Italy) with those of a standard gadolinium chelate (gadopentetate dimeglumine, Magnevist; Schering, Berlin, Germany) in primary and secondary brain tumors on the basis of qualitative and quantitative parameters, on an intraindiviual basis.

MATERIALS AND METHODS

Twenty-seven patients with either high-grade glioma or metastases were enrolled in a bicentric intraindividual crossover study to compare lesion enhancement with doses of 0.1 mmol per kilogram of body weight of 0.5 mol/L gadopentetate dimeglumine and 0.5 mol/L gadobenate dimeglumine. MR imaging was performed before injection (T1-weighted spin-echo [SE] and T2-weighted fast SE acquisitions) and at 1, 3, 5, 7, 9, and 16 minutes after injection (T1-weighted SE acquisitions). Qualitative assessment was performed by blinded off-site readers (for 22 patients) and on-site investigators (for 24 patients) in terms of global contrast enhancement, lesion-to-brain contrast, lesion delineation, internal lesion morphology and structure, tumor vascularization, and global image preference. Additional quantitative assessment with region-of-interest analysis was performed by off-site readers alone. Statistical analysis of qualitative data was performed with the Wilcoxon signed rank test, whereas a nonparametric approach was adopted for analysis of quantitative data.

RESULTS

Significant (P <.05) preference for gadobenate dimeglumine over gadopentetate dimeglumine was noted both off-site and on-site for the global assessment of contrast enhancement. For off-site readers 1 and 2 and the on-site investigators, respectively, gadobenate dimeglumine was preferred in 13, 17, and 16 patients; gadopentetate dimeglumine was preferred in four, four, and four patients; and equality was found in five, one, and four patients). Similar preference for gadobenate dimeglumine was noted by off-site readers and on-site investigators for lesion-to-brain contrast and all other qualitative parameters. Off-site quantitative evaluation revealed significantly (P <.05) superior enhancement for gadobenate dimeglumine compared with that for gadopentetate dimeglumine at all time points from 3 minutes after injection.

CONCLUSION

Significantly superior contrast enhancement of intraaxial enhancing brain tumors was achieved with 0.1 mmol/kg gadobenate dimeglumine compared with that with 0.1 mmol/kg gadopentetate dimeglumine.

Clinical experience with multihance in CNS imaging

The use of Gd-BOPTA as a contrast agent for morphological and functional MR imaging allows improved detection and delineation of CNS lesions compared with conventional gadolinium agents. This not only leads to more confident diagnoses being made, but also results in a substantially improved differential diagnostic process. The higher relaxivity of Gd-BOPTA helps to optimize functional MR imaging studies, for example, perfusion MR imaging and dynamic MR angiographic protocols.

Assessment of gadobenate dimeglumine for magnetic resonance angiography: phase I studies

RATIONALE AND OBJECTIVES

To assess the vascular contrasting properties of a new MR contrast agent (gadobenate dimeglumine [Gd-BOPTA]), which presents higher relaxivity because of reversible, weak protein interaction, and, to compare these properties with a standard gadolinium agent.

MATERIALS AND METHODS

Two phase I trials compared intraindividually: (A) the vascular contrasting properties of Gd-BOPTA at three doses (0.0125, 0.05, and 0.2 mmol/kg body weight) and two flow rates (0.5 and 2.0 mL/s) in 10 volunteers; and (B) 0.1 mmol/kg body weight doses of Gd-BOPTA and Gd-DTPA at 2.0 mL/s using a modified magnetic resonance angiography (MRA) sequence with a temporal resolution of 1 s/f. Quantitative (ROI analysis) and fully blinded qualitative (reader review) assessment of images was performed.

RESULTS

A dose of 0.2 mmol/kg resulted in higher maximum intensities, longer median peak widths, and larger areas under the curve than did the lower doses (0.0125 mmol/kg and 0.05 mmol/kg). In the intraindividual comparison, Gd-BOPTA demonstrated significantly better vascular enhancement characteristics in terms of signal peak duration (p < 0.05), maximum signal intensity (p < 0.05), and area under the enhancement curve (p < 0.01). The multireader assessment for overall vascular contrast preferred Gd-BOPTA at p < 0.03.

CONCLUSIONS

Gd-BOPTA was shown to exhibit preferential and different vascular enhancement properties as compared with Gd-DTPA for MRA.