Comparison of T2-weighted MRCP before and after injection of Gd-EOB-DTPA in patients with primary sclerosing cholangitis (PSC)

Transcription

1 Comparison of T2-weighted MRCP before and after injection of Gd-EOB-DTPA in patients with primary sclerosing cholangitis (PSC) Poster No.: C-0051 Congress: ECR 2010 Type: Scientific Exhibit Topic: Abdominal Viscera (Solid Organs) - Liver Authors: K. I. Ringe, R. T. Gupta, P. Bolzen, N. Hellige, T. Weissmüller, M. P. Manns, M. Galanski, E. Merkle, J. Lotz ; Hannover/DE, 2 Durham, NC/US Keywords: Gd-EOB-DTPA, MRCP, primary sclerosing cholangitis Keywords: Abdomen,, Liver DOI: /ecr2010/C-0051 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 22

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3 Purpose Magnetic Resonance Cholangiopancreatography (MRCP) is an established technique to evaluate the intra- and extrahepatic biliary tract in patients with primary sclerosing cholangitis (PSC). Gd-EOB-DTPA (Primovist ) is a hepatobiliary specific contrast agent characterized by hepatic uptake and biliary excretion of approximately 50%, allowing for additional data acquisition during the hepatocyte phase. A standard MR protocol for assessment of the hepatobiliary system comprises in addition to a classical T2w MRCP T1 and T2w sequences before contrast injection, a dynamic liver contrast study and delayed hepatocyte phase images at 20 minutes for Gd-EOB-DTPA. It has been proposed that workflow may be optimized by acquiring T2w sequences in the time interval between completion of the dynamic contrast enhanced series and the onset of the hepatocyte phase. The purpose of this study was to test whether visualization of the intra- and extrahepatic bile ducts with a respiratory triggered 3D T2w MR cholangiography (3D MRC) is influenced by Gd-EOB-DTPA in patients with known PSC. Page 3 of 22

4 Images for this section: Fig. 0: Table 1: Clinical indications of the study population. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 4 of 22

5 Fig. 0: Table 2: MR pulse sequence protocol. Sequence #3 and #6 were identical with a time to central k-space filling of approximately 3 minutes. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Fig. 0: Figure 2: Signal-to-noise ratio (SNR) in the extrahepatic bile tract before and after injection of Gd-EOB-DTPA in 60 patients. Overall, mean SNR before and after contrast injection were 96 ± 50 and 78 ± 47, with the difference being statistically significant (p Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 5 of 22

6 Fig. 0: Figure 1: For SNR measurements a ROI was placed within the extrahepatic biliary tract (1). Noise estimates were derived from a region outside the body in the vicinity of the liver (2). Signal-to-noise ratios were calculated as follows: Mean signal of the bile duct divided by the standard deviation of the noise. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 6 of 22

7 Methods and Materials Patients This retrospective HIPAA-compliant dual center (Hannover Medical School, Germany and Duke University Medical Center, USA) study was IRBapproved with a waiver of informed consent granted. From July through December 2008, 60 patients (18-82 years; proven PSC n=13, non PSC=47 including other parenchymal diseases; 32 male, 28 female) who were referred for liver MRI with Gd-EOB-DTPA were included in this study (Table 1). Fig.: Table 1: Clinical indications of the study population. References: Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/ DE MR Imaging MRI examinations were performed on either a 1.5T (Magnetom Avanto, Siemens n=27; Signa HDx GE n=13) or 3T system (Magnetom Tim Trio, Siemens n=20). In all patients multi-channel surface coils covering the whole abdomen were used. All patients received a routine clinical imaging protocol including a 3D MRC just before the dynamic contrast series with a maximum dose of 10 ml Page 7 of 22

8 Gd-EOB-DTPA at 2mL/sec followed by a saline flush using a dual power injector. In addition to the clinical routine imaging protocol, the 3D MRC was repeated immediately after completion of the portal venous phase series, specifically within 6 minutes after contrast injection (Table 2). Fig.: Table 2: MR pulse sequence protocol. Sequence #3 and #6 were identical with a time to central k-space filling of approximately 3 minutes. References: Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/ DE Analysis Quantitative signal-to-noise (SNR) measurements were performed in the extrahepatic biliary tract in both MRC datasets of each patient by placing 2 an oval ROI (range 6-180mm ) in the common hepatic duct or common bile duct (Figure 1). In addition, an SNR-index was defined for each patient as SNR (before contrast injection) divided by SNR (after contrast injection). Statistical analysis consisted of a one-sided Wilcoxon signed rank test with α < 0.05 deemed significant. Page 8 of 22

9 Fig.: Figure 1: For SNR measurements a ROI was placed within the extrahepatic biliary tract (1). Noise estimates were derived from a region outside the body in the vicinity of the liver (2). Signal-to-noise ratios were calculated as follows: Mean signal of the bile duct divided by the standard deviation of the noise. References: Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/ DE Page 9 of 22

10 Images for this section: Fig. 0: Table 2: MR pulse sequence protocol. Sequence #3 and #6 were identical with a time to central k-space filling of approximately 3 minutes. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 10 of 22

11 Fig. 0: Table 1: Clinical indications of the study population. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Fig. 0: Figure 1: For SNR measurements a ROI was placed within the extrahepatic biliary tract (1). Noise estimates were derived from a region outside the body in the vicinity of the liver (2). Signal-to-noise ratios were calculated as follows: Mean signal of the bile duct divided by the standard deviation of the noise. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 11 of 22

12 Results 1. There was a significant drop of mean SNR in the MRC after injection of Gd-EOBDTPA with the SNR before and after contrast being 96 ± 50 and 78 ± 47, respectively (p<0.0001) (Figures 2-5). 2. A subgroup analysis revealed a statistically significant difference between patients with parenchymal disease (SNR-index 1.15 ± 0.27) and those without (SNR-index 2.12 ± 2.85) (p=0.03) but 3. no significant difference between patients with PSC (SNR index 1.27±0.27) and patients without PSC (SNR index 1.8 ± 2.44) (p=0.078). 4. There was no statistically significant difference in SNR comparing sequences acquired using 1.5T and 3T magnets (p=0.778). Fig.: Figure 2: Signal-to-noise ratio (SNR) in the extrahepatic bile tract before and after injection of Gd-EOB-DTPA in 60 patients. Overall, mean SNR before and after contrast injection were 96 ± 50 and 78 ± 47, with the difference being statistically significant (p References: Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/ DE Page 12 of 22

13 Fig.: Figure 3: 34 year old male patient with known PSC. Coronal T2w 3D MRC before (A) and after (B) injection of gadoxetate disodium. After contrast injection there is discrete loss of peripheral bile duct visualization (arrow). References: Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/ DE Page 13 of 22

14 Fig.: Figure 4: 58 year old female with central stenosis (arrow) of the proximal common hepatic duct and suspicion of PSC. Coronal T2w 3D MRC before (A) and after (B) injection of gadoxetate disodium. Prior to contrast injection, the entire biliary tract is clearly depicted without artifacts. After contrast injection only parts of the common bile duct and few intrahepatic branches can be seen. Note that the stenosis of the proximal common hepatic duct is seen clearly on the pre contrast MRC. References: Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/ DE Page 14 of 22

15 Fig.: Figure 5: 49 year old male patient with history of liver metastases from colon cancer. Coronal T2w 3D MRC before (A) and after (B) injection of gadoxetate disodium. Before contrast injection, the entire biliary tract is clearly depicted without artifacts. After contrast injection only the distal common bile duct (arrow) can be seen, whereas the right hepatic duct, left hepatic duct, and higher order biliary branches are not visualized at all. References: Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/ DE Page 15 of 22

16 Images for this section: Fig. 0: Figure 2: Signal-to-noise ratio (SNR) in the extrahepatic bile tract before and after injection of Gd-EOB-DTPA in 60 patients. Overall, mean SNR before and after contrast injection were 96 ± 50 and 78 ± 47, with the difference being statistically significant (p Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 16 of 22

17 Fig. 0: Figure 4: 58 year old female with central stenosis (arrow) of the proximal common hepatic duct and suspicion of PSC. Coronal T2w 3D MRC before (A) and after (B) injection of gadoxetate disodium. Prior to contrast injection, the entire biliary tract is clearly depicted without artifacts. After contrast injection only parts of the common bile duct and few intrahepatic branches can be seen. Note that the stenosis of the proximal common hepatic duct is seen clearly on the pre contrast MRC. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 17 of 22

18 Fig. 0: Figure 3: 34 year old male patient with known PSC. Coronal T2w 3D MRC before (A) and after (B) injection of gadoxetate disodium. After contrast injection there is discrete loss of peripheral bile duct visualization (arrow). Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 18 of 22

19 Fig. 0: Figure 5: 49 year old male patient with history of liver metastases from colon cancer. Coronal T2w 3D MRC before (A) and after (B) injection of gadoxetate disodium. Before contrast injection, the entire biliary tract is clearly depicted without artifacts. After contrast injection only the distal common bile duct (arrow) can be seen, whereas the right hepatic duct, left hepatic duct, and higher order biliary branches are not visualized at all. Institut für Radiologie, Medizinische Hochschule Hannover - Hannover/DE Page 19 of 22

20 Conclusion 1. Prior injection of Gd-EOB-DTPA adversely affects a T2w MR cholangiography by means of significant signal reduction. 2. Signal loss, and thus loss of visualization of the bile ducts could mimic a biliary pathology, such as a stenosis. 3. Respiratory triggered 3D T2w MR-cholangiography sequences should be acquired before the injection of Gd-EOB-DTPA, also in patients with known PSC. Page 20 of 22

21 References Hekimoglu K, Ustundag Y, Dusak A, et al. MRCP vs. ERCP in the evaluation of biliary pathologies: review of current literature. J Dig Dis 2008; 9: Malone D, Zech CJ, Ayuso C, et al. Magnetic resonance imaging of the Liver: Consensus statement from the 1st International Primovist User Meeting. Eur Radiol 2008; 18:Suppl 4 [D1-D16] Ringe KI, Gupta RT, Brady CM et al. Respiratory triggered 3D T2w MR Cholangiography after the injection of Gadoxetate Disodium: is it still reliable? Radiology in press Schuhmann-Giampieri G, Schmitt-Willich H, Press WR, et al. Preclinical evaluation of Gd-EOB-DTPA as a contrast agent in MR imaging of the hepatobiliary system. Radiology 1992; 183: Page 21 of 22

22 Personal Information Kristina Imeen Ringe, M.D. Hannover Medical School Department of Radiology Carl-Neuberg-Str Hannover Germany Contact: ringe.kristina@mh-hannover.de Page 22 of 22