Magnetic resonance cholangiography with mangafodipir trisodium (Teslascan) to evaluate bile duct leaks after T-tube removal in liver transplantation

Liver transplant patients who present with abdominal pain after removal of the T-tube can be initially evaluated by contrast-enhanced magnetic resonance cholangiography (CEMRC) instead of abdominal computed tomography and hepatobiliary scintigraphy. In this article, 3 liver transplant patients who were evaluated by CEMRC after removal of the T-tube. CEMRC successfully identified the presence, location and extent of bile duct leaks, and can be performed as a diagnostic study in patients with suspected bile duct leaks.     

Detection of bile duct leaks using MR cholangiography with mangfodipir trisodium (Teslascan)

Mangafodipir trisodium (Teslascan), a hepatobiliary contrast agent, has the potential of providing functional biliary imaging similar to hepatobiliary scintigraphy. To our knowledge. the potential role of this biliary contrast agent in the detection of bile duct leaks has not been reported. In this case report, we report the first case of a bile duct leak diagnosed with enhanced MRI with mangafodipir trisodium in a patient following laparoscopic cholecystectomy. Our case illustrates that functional MR cholangiography images can be successfully acquired by using a post-mangafodipir fat-suppressed GRE technique and that bile duct leaks can be detected.     

Value of MR cholangiography in patients with iatrogenic bile duct injury after cholecystectomy

OBJECTIVE: Our aim was to determine the diagnostic role of MR cholangiography in the evaluation of iatrogenic bile duct injuries after cholecystectomy. SUBJECTS AND METHODS: Nineteen patients (14 women and five men; mean age, 47 years; age range, 24-75 years) with suspected bile duct injury as a result of laparoscopic cholecystectomy (17 patients) and open cholecystectomy (two patients) underwent MR cholangiography. MR images were evaluated for bile duct discontinuity, presence or absence of biliary dilation, stricture, excision injury, free fluid, and collections. Bile duct excision and stricture were classified according to the Bismuth classification. Final diagnosis was made on the basis of findings at surgery in 15 patients, on percutaneous transhepatic cholangiography (PTC) in one patient, and on endoscopic retrograde cholangiography (ERC) and at clinical follow-up until hospital discharge in the remaining three patients. RESULTS: In 16 patients, injury of the bile duct was observed. Two patients had Bismuth type I injury; one patient, type II injury; 11 patients, type III injury; and one patient each, type IV and V injuries. Three patients showed findings suggestive of leakage from the cystic duct remnant, which were confirmed on ERC. CONCLUSION: MR cholangiography is an accurate diagnostic technique in the identification of postoperative bile duct injuries. This technique allows exploration above and below the level of obstruction, a resource provided by neither ERC nor PTC, and allows the accurate classification of these injuries, which is essential for treatment planning.     

New possibilities to study biliary tree and gallbladder: functional magnetic resonance cholangiography contrast-enhanced with mangafodipir trisodium (Mn DPDP)

Mangafodipir trisodium (Teslascan) is a hepatobiliary contrast agent that provides noninvasive opacification of the bile ducts. Using this contrast medium combined with a T1-weighted gradient echo enhanced sequence provides functional imaging of the bile ducts. Second-intention MRI was obtained after the usual morphological study of the bile ducts using heavily T2-weighted sequences (SS-FSE Te eff long and SS FSE Te eff short). This method can detect many biliary duct anomalies: biliary leakage in the postoperative context, mapping of bile ducts and the gallbladder in the search for anatomical variants, analysis of biliodigestive or biliobiliary anastomoses, or a dynamic study of bile secretion and excretion. Opacification of the bile ducts has only been possible until now with invasive tests aggravated by a certain co-morbidity rate and their functional study using biliary scintigraphy limited by mediocre spatial resolution. This new possibility provides access not only to morphological imaging, but also to functional imaging with excellent spatial resolution.     

Hepatic transplant complicated by hepatic artery thrombosis and bile duct necrosis: case report and potential application of contrast-enhanced MR cholangiography following intravenous mangafodipir trisodium in the emergency room setting

Biliary tract strictures and leaks are the second most common complications following orthotopic liver transplantation. Nonanastomotic bile duct complications are most often caused by hepatic artery thrombosis and can result in fulminant hepatic necrosis, bile duct strictures, and bile duct leaks that increase the risk of cholangitis, sepsis, and abscess. The emergency physician and radiologist should strongly suspect biliary disease in a post-transplant patient presenting with elevated liver function tests, jaundice, fever, and/or abdominal pain in order to achieve diagnosis and treatment rapidly. We present the case of a liver transplant patient who developed bile duct necrosis and hepatic infarction secondary to hepatic artery thrombosis 5 months after surgery. In addition, we discuss a new contrast-enhanced MR cholangiographic technique that has the potential to be performed in the emergency setting as the only diagnostic test prior to appropriate therapy. Electronic Publication     

Detection of common bile duct stones before laparoscopic cholecystectomy. Evaluation with MR cholangiography

Purpose:
To assess the diagnostic value of MR cholangiography (MRC) for detecting common bile duct (CBD) stones in candidates for laparoscopic cholecystectomy (LC). Material and Methods:
A series of 95 selected patients with gallstones and suspected CBD lithiasis (abnormal serum liver tests and/or CBD size ≥6.5 mm at US) were referred to our institution for MRC, before LC. MRC was performed on a 0.5 T magnet through a non-breath-hold, respiratory-triggered, fat-suppressed, thin-slab, heavily T2-weighted fast spin-echo sequence and through a breath-hold, thick-slab, single-shot T2-weighted sequence in the coronal plane. Axial T1- and T2-weighted sequences were first obtained. Two observers in conference reviewed source images and maximum intensity projections to determine the presence or absence of choledocholithiasis. MR findings were compared with endoscopic retrograde cholangiography and intraoperative cholangiography (IOC); IOC was always performed during LC. Results:
CBD calculi (single or multiple) were identified in 41 out of 95 patients (43%). Two false-positive and 4 false-negative cases were found on MRC. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MRC for choledocholithiasis were 90%, 96%, 94%, 95%, and 93%, respectively. Conclusion:
MRC is a highly effective diagnostic modality for evaluation of patients with risk factors for CBD stones prior to LC.     

Hepatic bile duct hamartomas (von Meyenburg Complexes): MR and MR cholangiography findings

Multiple bile duct hamartomas (MBDHs) of the liver, also known as von Meyenburg complexes, are easily confused with diffuse metastatic disease of the liver on US and CT. At present, histologic examination after tissue preevaluation is usually necessary for definite diagnosis. We report four cases in which the MR features, and especially the MR cholangiographic (MRC) findings, were highly suggestive for MBDH. Characteristic findings include multiple markedly hyperintense nodules on T2-weighted imaging, typically measuring <1.5 cm; no communication with the biliary tree; and irregular delineation of the lesions with no or slight rim enhancement following gadolinium administration.     

Diagnosing bile duct stones: comparison of unenhanced helical CT, oral contrast-enhanced CT cholangiography, and MR cholangiography

OBJECTIVE. In this investigation we compared the diagnostic performance of unenhanced helical CT, oral contrast-enhanced CT cholangiography, and MR cholangiography for the diagnosis of choledocholithiasis. SUBJECTS AND METHODS. Fifty-one patients referred for endoscopic retrograde cholangiography of suspected biliary stones were studied with unenhanced helical CT, MR cholangiography, and helical CT performed after oral administration of a cholangiographic contrast agent (iopodic acid). The studies were randomized for interpretation. Two radiologists evaluated the images by consensus and determined the presence and location of stones. We used retrograde cholangiography findings as the standard of reference. Sensitivity and specificity (with 95% confidence intervals [CIs]) of the three examinations were calculated and compared using the exact form of the McNemar test. RESULTS. Bile duct stones were revealed with retrograde cholangiography in 26 patients (51%). Sensitivity was 65% (95% CI, 44.4-82%) for unenhanced helical CT, 92% (95% CI, 73-99%) for CT cholangiography, and 96% (95% CI, 78-99%) for MR cholangiography. Specificity was 84% (95% CI, 63-95%) for unenhanced helical CT, 92% (95% CI, 73-99%) for CT cholangiography, and 100% (95% CI, 83-100%) for MR cholangiography. The sensitivity of CT cholangiography and MR cholangiography was significantly higher than that of unenhanced helical CT (p<0.01). Differences in specificity were not significant. CONCLUSION. Our results indicate that oral contrast-enhanced CT cholangiography and MR cholangiography are significantly more sensitive than unenhanced helical CT for the detection of bile duct calculi.     

Early biliary complications of laparoscopic cholecystectomy: evaluation on T2-weighted MR cholangiography in conjunction with mangafodipir trisodium-enhanced 3D T1-weighted MR cholangiography

OBJECTIVE: Our aim was to assess preliminary experience with combined conventional T2-weighted and mangafodipir trisodium (MnDPDP)-enhanced T1-weighted MR cholangiography in evaluating early biliary complications of laparoscopic cholecystectomy. SUBJECTS AND METHODS: Conventional heavily T2-weighted MR cholangiography with MnDPDP-enhanced T1-weighted MR cholangiography and ERCP were performed in seven patients with high clinical suspicion of biliary complications after laparoscopic cholecystectomy. The final diagnoses of complications were classified according to the presence and degree of bile duct injury, bile leakage, and retained stones. RESULTS: The diagnoses on MR cholangiography were as follows: complete transection and occlusion of the common bile duct with bile leakage (n = 3), partial strictures of the common bile duct with bile leakage (n = 1), cystic duct leakage (n = 1), partial ligation of an aberrant right hepatic duct (n = 1), and hemorrhage without biliary complication (n = 1). The final diagnoses at surgery (n = 2) and ERCP (n = 5) were as follows: complete transection and occlusion of the common bile duct with bile leakage (n = 2), partial strictures of the common bile duct with bile leakage (n = 2), cystic duct leakage (n = 1), partial ligation of an aberrant right hepatic duct (n = 1), and hemorrhage without biliary complication (n = 1). MR cholangiography accurately yielded the same findings as the final diagnoses, except in one case with partial stricture of the bile duct with bile leakage (overdiagnosed as complete occlusion on MR cholangiography). CONCLUSION: Combined conventional T2-weighted and MnDPDP-enhanced T1-weighted MR cholangiography may eliminate the use of other studies for the imaging of biliary complications after cholecystectomy if this preliminary data can be verified in a larger study.     

Value of MRCP with Mangafodipir Trisodium (Teslascan) injection in the diagnosis and management of bile leaks

PURPOSE: To assess the value of MRCP with Mangafodipir Trisodium (Teslascan) injection in the diagnosis and management of bile leaks. PATIENTS AND METHODS: Retrospective study of 25 patients (18 males, 7 females) with a mean age of 49.7 years and high clinical suspicion of bile leak who underwent MRCP with Mangafodipir Trisodium (Teslascan) injection between 2002 and 2006. The suspected etiology for bile leak was surgical (n=17), traumatic (n=7) or medical (n=1). The clinical suspicion was based on a combination of clinical, laboratory and imaging findings. RESULTS: MRCP with Teslascan injection demonstrated a bile leak in 20 patients. The site of leak was depicted in 17 cases: second order of smaller bile duct, (n=9), hepatic duct (n=3), confluence (n=2), cystic duct (n=1), bilioenteric anastomosis (n=2). Management based on MR findings included biloma drainage (n=7), biliary drainage (n=5), endoscopic management (n=2), repeat surgery (n=3), expectant management (n=1), and medical management (n=1). Outcome was favourable in 18 cases. Two patients died from infectious complications. CONCLUSION: In addition to confirming a diagnosis of bile leak, MRCP with Teslascan injection depicts the site of leak allowing optimal management.     

Double common bile duct: curved-planar reformatted computed tomography (CT) and gadobenate dimeglumine-enhanced MR cholangiography

We present the case of a 61-year-old female with double common bile duct (CBD) with an opening into the lesser curvature of the stomach. We discuss the role of curved-planar reformatted computed tomography (CT) and gadobenate dimeglumine (Gd-BOPTA)-enhanced T1-weighted MRI in confirming the diagnosis of this uncommon disease.     

MR cholangiopancreatography versus endoscopic sonography in suspected common bile duct lithiasis: a prospective, comparative study

OBJECTIVE: Our purpose was to compare the accuracy of MR cholangiopancreatography and endoscopic sonography for the diagnosis of common bile duct stones in patients with a mild to moderate clinical suspicion of common bile duct stones. SUBJECTS AND METHODS: Forty-seven patients were prospectively enrolled. Inclusion criteria included acute pancreatitis, subclinical jaundice, and clinical features of common bile duct stone migration. Radial endoscopic sonography and MR cholangiopancreatography with the single-shot fast spin-echo technique were performed a maximum of 48 hr apart. The gold-standard diagnosis was obtained with ERCP (n = 20) or intraoperative cholangiography (n = 14) if the results of endoscopic sonography or MR cholangiopancreatography were abnormal or if a cholecystectomy was performed, or by clinical and biochemical follow-up (n = 11) if the results of endoscopic sonography and MR cholangiopancreatography were normal. RESULTS: The final diagnosis was common bile duct stones in 16 patients, malignant obstructions in four, and another biliary disease in two (lithiasis migration aspect with papillary edema); 23 patients had no biliary disease. The sensitivity and specificity of MR cholangiopancreatography were, respectively, 90.5% and 87.5% for etiologic diagnosis and 87.5% and 96.6% for the detection of common bile duct stones. The corresponding values for endoscopic sonography were 86.4% and 91.3% for etiologic diagnosis and 93.8% and 96.6% for visualization of choledocholithiasis. Accuracy did not significantly differ between the techniques. CONCLUSION: In cases of mild to moderate suspicion of choledocholithiasis, the accuracies of endoscopic sonography and MR cholangiopancreatography are similar. Because MR cholangiopancreatography is noninvasive, it may be preferred for this indication.     

Dynamic contrast-enhanced MR imaging in predicting progression of enhancing lesions persisting after standard treatment in glioblastoma patients: a prospective study

Objectives

To prospectively explore the value of dynamic contrast-enhanced magnetic resonance imaging (DCE–MRI) in predicting the progression of enhancing lesions persisting after standard treatment in patients with surgically resected glioblastoma (GBM).

Methods

Forty-seven GBM patients, who underwent near-total tumorectomy followed by concurrent chemoradiation therapy (CCRT) with temozolomide (TMZ) between May 2014 and February 2016, were enrolled. Twenty-four patients were finally analyzed for measurable enhancing lesions persisting after standard treatment. DCE-MRI parameters were calculated at enhancing lesions. Mann–Whitney U tests and multivariable stepwise logistic regression were used to compare parameters between progression (n?=?16) and non-progression (n?=?8) groups.

Results

Mean K^trans and v_e were significantly lower in progression than in non-progression (P?=?0.037 and P?=?0.037, respectively). The 5th percentile of the cumulative K^trans histogram was also significantly lower in the progression than in non-progression group (P?=?0.017). Mean v_e was the only independent predictor of progression (P?=?0.007), with a sensitivity of 100%, specificity of 63%, and an overall accuracy of 88% at a cut-off value of 0.873.

Conclusions

DCE-MRI may help predict the progression of enhancing lesions persisting after the completion of standard treatment in patients with surgically resected GBM, with mean v_e serving as an independent predictor of progression.

Key points

? Enhancing lesions may persist after standard treatment in GBM patients.? DCE-MRI may help predict the progression of the enhancing lesions.? Mean K ^trans and v _e were lower in progression than in non-progression group.? DCE-MRI may help identify patients requiring close follow-up after standard treatment.? DCE-MRI may help plan treatment strategies for GBM patients.

     

Carotid and vertebral artery stenosis evaluated by contrast-enhanced MR angiography in nasopharyngeal carcinoma patients after radiotherapy: a prospective cohort study

Objective:

To investigate the incidence of carotid artery (CA) and vertebral artery (VA) stenosis by contrast-enhanced MR angiography (CE-MRA) in patients with nasopharyngeal carcinoma (NPC) after radiotherapy.

Methods:

72 patients with NPC after radiotherapy more than 3 years ago were recruited as irradiation group to investigate the incidence and degree of CA and VA stenosis by CE-MRA. The results were compared with those of the control group, which comprised 50 newly diagnosed patients with NPC who had not received radiotherapy.

Results:

There was a higher incidence of CA and VA stenosis in the irradiation group than in the control group in terms of patient number as well as vessel involvement. The incidence of significant (>50%) CA and VA stenosis, except for the basilar artery, was also higher in the irradiation group than in the control group. The most commonly detected stenosis in the irradiation group was found in the internal CA (ICA) and VA, followed by the external CA and common CA (CCA). CCA and/or ICA (CCA/ICA) stenosis was present in 67 (93.1%) of 72 patients, with 27 (37.5%) patients having significant CCA/ICA stenosis. The statistical analysis demonstrated that age at receiving CE-MRA scanning and time interval from radiotherapy were the independent predictors of significant CCA/ICA stenosis.

Conclusion:

The CE-MRA scanning results showed that the incidence of stenosis seems to exist in a wider range of CAs and VAs in the patients with NPC after radiotherapy than in the patients who had not received radiotherapy, and the incidence of significant CCA/ICA stenosis is higher in patients with older age and longer interval from radiotherapy.

Advances in knowledge:

Radiation-induced CA and VA stenosis exists widely in patients with NPC after radiotherapy, and its prevalence is more common in patients with older age and longer interval from radiotherapy.Nasopharyngeal carcinoma (NPC) is one of the most common malignancies in China, and radiotherapy remains the standard treatment for these patients. Ongoing improvements in radiotherapeutic techniques and chemoradiotherapy have resulted in excellent locoregional control and survival rates in these patients, even in those with locally advanced disease.¹ Therefore, a significant proportion of patients are long-term survivors, and late complications of radiotherapy, such as temporal lobe necrosis, endocrine dysfunction, xerostomia, fibrosis of soft tissue and ear complications, are of utmost concern for patients and radiation oncologists.^2,3 In addition, carotid and vertebral artery (VA) stenosis is also a well-documented late complication of radiotherapy in patients with NPC because severe carotid stenosis is associated with a high risk of stroke.^3–5Diagnostic methods that are used to identify carotid artery (CA) and VA stenosis include digital subtraction angiography (DSA), ultrasonography, CT angiography (CTA) and MR angiography (MRA). DSA is the gold standard for the diagnosis and quantification of carotid stenosis. However, DSA is an invasive method with several limitations, including risk of neurological complications and the potential for variability in the quantification of stenosis. Hence, the diagnostic role of DSA has largely been replaced by non-invasive techniques such as ultrsonography, CTA and MRA.^6,7 Colour Doppler ultrasonography (CDUS), as a rapid, readily available and low-cost technique, has been widely used in the clinic but may be restricted by its instability, operator dependence and limited coverage. Moreover, CDUS cannot provide three-dimensional (3D) and complete visualization of the anatomical structures.⁸ CTA has the advantages of high spatial resolution, fast imaging and ease of calcified plaque identification. However, the patient needs to receive ionizing radiation.⁷ MRA, including non-enhanced MRA and contrast-enhanced MRA (CE-MRA), is considered to be a safe, convenient and non-invasive tool for detecting vessel stenosis.^7–9 However, non-enhanced MRA is limited by local reduction of signal intensity related to slow and turbulent flow and also prolongs the imaging time.¹⁰ CE-MRA helps to overcome these limitations.^7,11 Several studies revealed that CE-MRA was similarly accurate to CTA for evaluating carotid stenosis but was more accurate than CDUS.^7–9 In most of the previous studies, radiation-induced CA and VA stenosis has been evaluated by ultrasonography and DSA in head and neck cancers,^2–4 but few studies have assessed stenosis by CE-MRA. Therefore, we undertook the present prospective study in patients with NPC after receiving radiotherapy more than 3 years ago using newly diagnosed patients with NPC as control and investigated the incidence of CA and VA stenosis by CE-MRA.     

Preoperative assessment of longitudinal extent of bile duct cancers using MDCT with multiplanar reconstruction and minimum intensity projections: comparison with MR cholangiography

Objective

To compare the performance of MDCT, including multiplanar reformation (MPR) and minimum intensity projection (MinIP) images, with that of transaxial MDCT with MR cholangiography (MRC) in the preoperative evaluation of the longitudinal extent of bile duct cancer.

Methods

Twenty-seven patients with surgically proven bile duct cancer, who had undergone preoperative multiphasic MDCT and MRC, were included. Two radiologists evaluated the MDCT set with MPR and MinIP images and the image set of transaxial MDCT with MRC, regarding the longitudinal extent of bile duct cancer. The results were compared with the surgical and pathology findings.

Results

The area under the receiver operating characteristic curves of the MDCT set with MPR and MinIP images and the image set of transaxial MDCT with MRC for predicting the longitudinal extent of bile duct cancer, were 0.938, 0.923 and 0.839, 0.836 for both reviewers. The differences were not statistically significant for either image set or either reviewer. The sensitivity and specificity of the MDCT image set for detecting tumor involvement of the biliary second confluences or intrapancreatic segment were similar for both reviewers to those of transaxial MDCT with MRC.

Conclusions

MDCT with MPR and MinIP images showed comparable diagnostic performance to that of transaxial MDCT with MRC for predicting the longitudinal extent of bile duct cancer.     

Magnetic resonance cholangiography of biliary strictures after liver transplantation: a prospective double-blind study

PURPOSE: To compare magnetic resonance cholangiography (MRC) with endoscopic retrograde cholangiography (ERC) in quantitatively evaluating biliary strictures in liver transplant recipients. MATERIALS AND METHODS: Eight liver transplant recipients with suspected biliary complications were referred for ERC and also underwent MRC within 24 hours using a combination of single-shot rapid acquisition with relaxation enhancement (SS-RARE) and three-dimensional (3D)-RARE sequences. The studies were independently interpreted by two blinded radiologists and a single blinded endoscopist who recorded the presence of a stricture and/or upstream dilatation, the ratio of recipient-to-donor duct diameters at the anastomosis, as well as the proximal duct diameter, length, and percent stenosis of any stricture detected. RESULTS: Using ERC as the standard of reference, MRC had a sensitivity and negative predictive value of 100%, mean specificity of 83.3%, and mean positive predictive value of 92.9% in the detection of six strictures. Compared with ERC, MRC obtained accurate measurements of recipient-to-donor duct diameter ratios (r, 0.91; P < 0.01), proximal duct diameters (r, 0.83, P < 0.05), stricture lengths (r, 0.58; P = 0.06), and percent stenosis (r, 0.78; P = 0.06). CONCLUSION: MRC can provide equivalent imaging to ERC and can reliably identify and quantitatively evaluate biliary strictures in post-orthotopic liver transplantation (OLT) patients.