Quantitative and qualitative comparison of 0.025 mmol/kg gadobenate dimeglumine for abdominal MRI at 1.5T and 3T MRI in patients with low estimated glomerular filtration rate. Eur J Radiol. 2015;84:26-32. [PMID: 25467229 DOI: 10.1016/j.ejrad.2014.10.016]

Liver enhancement during hepatobiliary phase after Gd-BOPTA administration: correlation with liver and renal function

OBJECTIVES

To assess the influence of liver and renal function on liver relative enhancement during hepatobiliary phase MRI after Gd-BOPTA administration.

METHODS

In this IRB-approved retrospective cohort study, we included 326 patients who underwent Gd-BOPTA-enhanced 1.5T liver MRI, including hepatobiliary phase (HBP) acquired 90-150 min after injection, in two centres between Jan 2016 and Dec 2019. Liver signal intensity was measured on native and HBP phases and normalized to paraspinal muscles. Liver normalized relative enhancement (NRE) in HBP was calculated and compared with eGFR, total serum bilirubin and HBP acquisition delay by means of Spearman r correlation test and Mann-Whitney U test.

RESULTS

221/326 patients received 0.05 mmol/Kg Gd-BOPTA (group A), whereas 105/326 received 0.1 mmol/Kg (group B). Liver NRE in HBP was significantly higher in group B than in group A (0.55vs.0.33, p < 0.0001). In both groups, liver NRE in HBP had a negative correlation with total serum bilirubin level (r = - 0.32, p < 0.0001, group A; r = - 0.36, p = 0.0002, group B). Patients with total bilirubin > 1.2 mg/dl showed significantly lower NRE in HBP compared with those with total bilirubin ≤ 1.2 mg/dl (p < 0.0001, group A; p = 0.04, group B). Patients with impaired liver function in group B showed a NRE during HBP comparable with those with normal liver function in group A. No statistically significant correlation between liver NRE and eGFR or acquisition delay was observed.

CONCLUSIONS

The degree of liver enhancement during HBP is not correlated with eGFR or acquisition delay, but it is significantly reduced in patients with impaired liver function. 0.1 mmol/kg Gd-BOPTA dose might be useful in patients with total serum bilirubin > 1.2 mg/dl.

KEY POINTS

• The degree of liver enhancement during hepatobiliary phase after Gd-BOPTA administration has a negative correlation with total serum bilirubin level (r = - 0.32, p < 0.0001). • The degree of liver enhancement during HBP after Gd-BOPTA administration is not significantly correlated with renal function and acquisition delay (comprised between 90 and 150 min after contrast injection). • 0.1 mmol/Kg Gd-BOPTA dose might be preferable in patients with increased total serum bilirubin levels.

Gadolinium-based contrast agents: A comprehensive risk assessment

Gadolinium-based contrast agents (GBCAs) have been used in magnetic resonance imaging (MRI) since the 1980s and are now administered in up to 35% of all MRI examinations. While GBCAs were initially felt to carry minimal risk, the subsequent identification of GBCAs as the key etiologic factor in the development of nephrogenic systemic fibrosis (NSF) has raised concerns about the broader health impacts of gadolinium exposure. Clinicians, radiologists, and patients should be aware of the most up-to-date data pertaining to the risks of GBCA administration. Specific issues covered in this review article include immediate adverse reactions; pregnancy and lactation; and gadolinium deposition and toxicity, with a special focus on NSF. Practice recommendations based on the presented data, as well as current professional society guidelines, are provided for each section.

LEVEL OF EVIDENCE

1 Technical Efficacy: Stage 5 J. MAGN. RESON. IMAGING 2017;46:338-353.

Enhancement of abdominal structures on MRI at 1.5 and 3 T: a retrospective intraindividual crossover comparison

OBJECTIVE

To quantitatively compare the extent of enhancement of abdominal structures on MRI in an intraindividual fashion at 1.5 and 3 T.

METHODS

HIPAA-compliant, retrospective, longitudinal, intraindividual, crossover study, with waived informed consent, of consecutive individuals scanned at both 1.5 and 3 T closed-bore magnets using gadobenate dimeglumine during different phases of enhancement at tightly controlled arterial phase timing. Quantitative ROI measurements and qualitative sub-phase arterial phase assignments were independently performed by two radiologists. Qualitative discrepancies were resolved by a senior radiologist.

RESULTS

Final population included 60 patients [41 female and 19 male; age, 49.35 ± 18.31 years (range 16-81); weight, 78.88 ± 20.3 kg (range 44.5-136)]. Similar enhancement peak patterns were noted at both field strengths. Interobserver agreement of quantitative evaluations was substantial. Significantly higher amplitudes of enhancement peaks were noted for all abdominal solid organs during all phases at 3 T, except for the pancreas (p = 0.17-0.30). Significantly higher amplitudes of enhancement peaks of the abdominal aorta at 1.5 T were noted.

CONCLUSION

Similar peak patterns of enhancement for abdominal structures were observed at 1.5 and 3 T, with solid abdominal organs showing a higher percentage enhancement at 3 T, while unexpectedly higher aortic higher percentage enhancement was observed at 1.5 T.

KEY POINTS

• Similar enhancement peak patterns at both field strengths for studied abdominal structures. • Significantly higher percentage enhancement of most abdominal organs at 3 T. • Non-statistically significant trend of higher pancreatic percentage enhancement at 3 T. • Significantly lower abdominal aortic percentage enhancement at 3 T.

3.0 Tesla magnetic resonance imaging: A new standard in liver imaging?

An ever-increasing number of 3.0 Tesla (T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimization of imaging protocols or implementation of novel hardware components. Clinical practice and literature review suggest that state-of-the-art 3.0 T is equivalent to 1.5 T in the assessment of focal liver lesions and diffuse liver disease. Therefore, further technical improvements are needed in order to fully exploit the potential of higher field strength.