Gadobenate dimeglumine as an intrabiliary contrast agent: comparison with mangafodipir trisodium with respect to non-dilated biliary tree depiction

Intravenous combined with intrabiliary contrast-enhanced ultrasound in the evaluation of resectability of hilar cholangiocarcinomas

OBJECTIVE

To investigate the application value of combined intravenous contrast-enhanced ultrasound (IV-CEUS) with intrabiliary contrast-enhanced ultrasound (IB-CEUS) in the preoperative evaluation of hilar cholangiocarcinoma (HCCA) resectability.

METHODS

Clinical data from 82 patients with HCCA confirmed by surgery and pathology were retrospectively analyzed. Preoperative IV-CEUS + IB-CEUS and magnetic resonance cholangiopancreatography (MRCP) were performed and the results were compared with surgical and pathological findings.

RESULTS

The accuracy of the Bismuth-Corlette classification confirmed by IV-CEUS + IB-CEUS and MRCP was 95.12% (78/82) and 87.8% (72/82), respectively. The diagnostic precision of IV-CEUS + IB-CEUS was better than MRCP (p = 0.001). The sensitivity, specificity, and precision of CEUS for diagnosing lymph node metastases (72.7%, 93.3%, and 87.8%), intrahepatic metastases (78.6%, 98.5%, and 93.9%), invasion of the hepatic artery (92.9%, 98.5%, and 97.6%) and invasion of the portal vein (93.8%, 98.5%, and 97.6%) of HCCA were, respectively. The consistency between the preoperative evaluation of resectability confirmed by IV-CEUS +IB-CEUS and MRCP was 85.4% (70/82) and 78.0% (64/82), respectively. In addition, the evaluations did not have statistically significant differences (p > 0.05). There were no significant differences between the two evaluations (p = 0.266).

CONCLUSION

IV-CEUS combined with IB-CEUS has significant value in classifying HCCA and evaluating the resectability of lymph node metastases, liver metastases, and vessel invasion.

Functional magnetic resonance cholangiography with Gd-EOB-DTPA: a study in healthy volunteers

PURPOSE

To describe the patterns of bile distribution in the biliary tree, duodenum, jejunum, and stomach, and to determine the gallbladder ejection fraction (GBEF) by using functional magnetic resonance cholangiography (MRC) with gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) in healthy volunteers.

MATERIALS AND METHODS

Forty subjects were included in this study. After conventional MRC, pre-fatty meal MRC (PRFM) was obtained at 30, 40, 50, and 60min after contrast agent injection. Then, post-fatty meal MRC (POFM) was obtained every 10min for 1h. We assessed the PRFM and POFM for opacification of contrast agent in the first- and second-order intrahepatic ducts (IHDs) and the common bile duct (CBD). Contrast agent opacification in the cystic duct was assessed, and the percentage volume of contrast agent filling in the gallbladder (GB) was calculated on PRFM. We calculated the GBEF and assessed the presence of contrast agent in the GB, duodenum, jejunum, and stomach.

RESULTS

Thirty-six (90%) subjects showed grade 3 CBD opacification (visible contrast and well-defined bile duct border) on 60-min PRFM. Thirty-four (85%) subjects showed grade 3 first-order IHD opacification on 60-min PRFM. All (100%) subjects showed cystic duct opacification of contrast agent, and the average percentage volume of contrast agent filling in the GB was 68.81%±16.84% on 60-min PRFM. The GBEF at 30-min POFM was 35.00%±18.26%. Ten (25%) subjects had no contrast agent in the stomach and small bowel on all PRFMs. Twelve (30%) subjects had contrast medium in the stomach on PRFM and/or POFM.

CONCLUSIONS

Functional MRC with Gd-EOB-DTPA can allow determining the distribution of bile in the biliary tree and small intestine, as well as the GBEF.

Functional MR cholangiography of the cystic duct and sphincter of Oddi using gadoxetate disodium: is a 30-minute delay long enough?

PURPOSE

To determine if excreted contrast is consistently visualized in the gallbladder and duodenum after a 30-minute delay using gadoxetate disodium-enhanced MRI in patients without hepatobiliary disease.

MATERIALS AND METHODS

Twenty-two patients without evidence of liver or biliary disease underwent gadoxetate disodium-enhanced magnetic resonance imaging (MRI) from February 17, 2009 through October 3, 2011. The mean age was 45 years (range 25-72). T1-weighted hepatobiliary phase images at 5, 10, 20, and 30 minutes after contrast injection were reviewed in consensus by two radiologists to determine the delay at which enhancement of the gallbladder and duodenum first occurred.

RESULTS

Thirteen of 22 (59.1%) patients demonstrated duodenal filling by 20 minutes and 16/22 (72.7%) filled by 30 minutes. The mean time to duodenal enhancement was 19.9 minutes (range 11.4-30.2 min). Seventeen of 22 (77.3%) patients demonstrated gallbladder filling by 20 minutes and 21/22 (95.5%) filled by 30 minutes. The mean time to gallbladder enhancement was 16.5 minutes (range 4.4-30.2 min).

CONCLUSION

A significant number of normal patients do not show duodenal filling by 30 minutes, while the majority fill the gallbladder by 30 minutes using functional MR cholangiography (fMRC) with gadoxetate disodium. These findings will guide fMRC protocol design for patients with suspected acute cholecystitis and sphincter of Oddi dysfunction.

Dynamic MR imaging of the biliary system using hepatocyte-specific contrast agents

OBJECTIVE

The objective of our study was to illustrate how the properties of hepatocyte-specific MR contrast agents can be used in the dynamic evaluation of the biliary system.

CONCLUSION

Because of their dual route of excretion through the kidneys and the liver, gadolinium-based, hepatocyte-specific MR contrast agents can be used to evaluate the biliary tract as an off-label use. Images are obtained during the hepatocyte phase, which usually occurs within 20-40 minutes after injection depending on the specific contrast agent selected. Potential uses include showing variant biliary anatomy and choledocholithiasis. Evaluation for acute cholecystitis is possible by assessing for reflux of contrast material across the cystic duct. Additionally, these agents have value in both presurgical and postsurgical imaging for showing anatomy and complications. Finally, these agents are useful in the evaluation of choledochal cysts.

Initial experience on utility of gadobenate dimeglumine (Gd-BOPTA) enhanced T1-weighted MR cholangiography in diagnosis of acute cholecystitis

PURPOSE

To investigate the feasibility of the use of gadobenate dimeglumine (also known as Gd-BOPTA) -enhanced T1-weighted MR cholangiography in diagnosis of acute cholecystitis.

MATERIALS AND METHODS

This prospectively designed institutional review board-approved HIPAA-compliant study was done between January and November 2007. We included 11 consecutive patients (7 male, mean age 59 years) who presented to the emergency room with acute right upper quadrant pain and with equivocal physical examination and/or ultrasound findings. The control group included 15 patients who underwent liver MRI with Gd-BOPTA. All patients underwent contrast-enhanced (CE) MR cholangiography examinations. CE-MR cholangiography was performed on a 1.5 Tesla magnet using 3D T1-weighted high resolution isotrophic volume examination (THRIVE) obtained at the 90th min after intravenous injection of Gd-BOPTA. Imaging features detected on CE-MR cholangiography were correlated with operative and histopathologic findings.

RESULTS

In the control group, GD-BOPTA was visualized within the gallbladder in all subjects. For the study group, gallstones were present in nine patients (n = 7 both in gallbladder and cystic duct, n = 1 only in gallbladder, n = 1 only in cystic duct) on MRCP. Hydropic gallbladder was detected in seven patients, significant wall thickening in seven patients, and pericholecystic free fluid in 6 patients. On delayed phase CE cholangiography, significant enhancement of gallbladder wall was seen in 10 patients, and contrast agent excretion into gallbladder was absent in all patients. Surgery was performed in 10 patients, and cholecystostomy was done in 1 patient. Surgery and histopathology findings were consistent with cholecystitis in all patients.

CONCLUSION

In addition to anatomical assessment, Gd-BOPTA-enhanced MR cholangiography can provide functional evaluation similar to HIDA scintigraphy in diagnosing acute cholecystitis in patients with acute right upper quadrant pain and equivocal findings.

Visualization of the biliary tract using gadobenate dimeglumine: preliminary findings

OBJECTIVE

To compare contrast-enhanced magnetic resonance (MR) cholangiography (CE-MRC) performed with gadobenate dimeglumine with T2-weighted MRC (T2-MRC) for visualization of the bile ducts in nondilated biliary systems.

MATERIALS AND METHODS

Twenty consecutive patients who underwent MR imaging (MRI) of the liver and pancreas with nondilated intrahepatic ducts were included in this retrospective study. T2-weighted MRC was performed using a multislice, high-resolution fat-suppressed half-Fourier acquisition turbo spin-echo sequence. Contrast-enhanced MR cholangiography was performed using a fat-suppressed 3-dimensional fast low-angle shot sequence acquired 1 to 1.5 hour after intravenous administration of gadobenate dimeglumine. For image interpretation, the biliary system was divided into 8 segments. Two readers graded visualization of each segment on T2-MRC and CE-MRC using a 5-point scale (0, nonvisualization; 4, excellent visualization). Final opinion for each sequence was rendered by consensus. Superiority of visualization was assessed using the McNemar test and comparing adequately (visualization scores 3 and 4) and inadequately (visualization scores 0, 1, and 2) visualized segments of the ducts on both sequences. Interobserver variability was assessed with kappa statistics.

RESULTS

Overall and segment-based evaluation revealed superior visualization of biliary segments with CE-MRC compared with T2-MRC. We also found a statistically significant difference between the 2 sequences for overall and for right hepatic duct and cystic channel visualization (P < 0.05). A high concordance between readers 1 and 2 both for T2-MRC and CE-MRC was achieved (85.8% and 89.4%, respectively).

CONCLUSIONS

Gadobenate dimeglumine can be used as an alternative intrabiliary contrast agent for contrast-enhanced MR cholangiography in nondilated biliary systems in patients with normal excretory liver function tests.

A serial dilution study of gadolinium-based MR imaging contrast agents

BACKGROUND AND PURPOSE

With the approval of gadobenate dimeglumine, higher relaxivity MR contrast agents were introduced into the clinical environment, and multiple in vivo studies compared the efficacy and safety with the previously approved agents. An in vitro study was conducted to demonstrate differences between the various agents to confirm published values and for imaging-sequence optimization.

MATERIALS AND METHODS

A contrast phantom was made with serial dilutions of commercially available formulations of 5 US Food and Drug Administration-approved gadolinium-based MR imaging contrast agents in human serum substitute. Dilution factors ranging from 1:8 to 1:4096 were included in the phantom. Spin-echo sequences were performed at 1.5T and 3T with varying TRs and TEs.

RESULTS

At physiologic concentrations and by using short TRs and TEs, gadobenate demonstrated the highest signal intensities, confirming greater R1 relaxivity. At higher concentrations and with longer TR and TE values, the greatest signal intensity loss was appreciated for gadobenate, confirming greater R2 relaxivity.

CONCLUSION

Using rigorous in vitro methodology and serial dilution techniques, this study confirms the reported higher R1 and R2 relaxivities of gadobenate relative to the other agents at 1.5T and 3T.

Liver MR Imaging: 1.5T versus 3T

This article focuses on technical challenges in transferring 1.5T liver protocols to 3T systems and the overall comparison of MR sequences, highlighting the advantages and disadvantages of imaging at the higher field strength. An important benefit is the capacity of acquiring high-quality, thin-section postgadolinium T1-weighted three-dimensional gradientecho sequences, most clinically relevant for the detection and characterization of small hypervascular malignant diseases. Further research and development is necessary to overcome disadvantages, such as with in- and out-of phase T1-weighted gradient-echo sequences, and to minimize artifacts that appear at 3T.