Hepatobiliary scintigraphy in the assessment of biliary obstruction after hepatic resection with biliary-enteric anastomosis

KSNM 60 in General Nuclear Medicine: the Old Dream Comes True

Since the establishment of the Korean Society of Nuclear Medicine (KSNM) in 1961 by Professor Munho Lee, the KSNM has been progressing in various medical fields. Many papers have been published in the Korean Journal of Nuclear Medicine (KJNM), the official journal of KSNM, since 1967 and other domestic/international journals. Here, we tried to highlight the academic activities of KSNM members from the perspective of general nuclear medicine. After the introduction of the ⁹⁹Mo/^99mTc generator, general nuclear medicine has widened the field of clinical application with the advancement of imaging technology and emerging new radiopharmaceuticals; however, there have been many ups and downs. Treatment, as well as diagnosis, was a major concern in Korean nuclear medicine. With the recent advent of single-photon emission computed tomography/computed tomography, we hope that our old dream (diagnosis and treatment under the same principle of nuclear medicine) comes true.

Accuracy of Hepatobiliary Scintigraphy after Liver Transplantation and Liver Resection

Background and Aims. Biliary complications are the most frequent complications after common liver surgeries. In this study, accuracy of hepatobiliary scintigraphy (HBS) and impact of hyperbilirubinemia were evaluated. Methods. Between November 2007 and February 2016, 131 patients underwent hepatobiliary scintigraphy after having liver surgery. 39 patients with 42 scans after LTX (n = 13) or hepatic resection (n = 26) were evaluated in the study; 27 were male, with mean age 60 years. The subjects underwent hepatobiliary scintigraphy with Tc-99m labeled Mebrofenin. The results were compared to ERCP as gold standard performed within one month after HBS. We calculated sensitivity, specificity, PPV, and NPV. We compared LTX patients to patients with other liver surgeries. Furthermore the influence of hyperbilirubinemia on HBS scans was evaluated. Results. HBS always provided the correct diagnosis in cases of bile leak in the liver-resected group (14/14). Overall diagnostic accuracy was 76% (19/25) in this group and 54% (7/13) in the LTX group. False negative (FN) diagnoses occurred more often among LTX patients (p = 0.011). Hyperbilirubinemia (>5 mg/dL) significantly influenced the excretion function of the liver, prolonging HBS's time-activity-curve (p = 0.001). Conclusions. Hepatobiliary scintigraphy is a reliable tool to detect biliary complications, but reduced accuracy must be considered after LTX.

MR evaluation of biliary-enteric anastomotic stricture: does contrast-enhanced T1W MRC provide additional information?

BACKGROUND AND OBJECTIVE

To compare T2W-MRCP and T1W contrast-enhanced MRC (CE-MRC) using Gd-BOPTA for evaluation of biliary-enteric anastomotic (BEA) stricture.

PATIENTS AND METHODS

Twenty-one patients who were suspected to have BEA stricture underwent T2W-MRCP and CE-MRC on a 1.5T scanner. Images were evaluated for evidence of anastomotic stricture. Composite gold standard was used including the findings on percutaneous transhepatic cholangiogram or percutaneous transhepatic biliary dilatation, surgery, alkaline phosphatase level and clinical follow-up.

RESULTS

The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of T2W-MRCP for the diagnosis of anastomotic stricture were 94.4%, 80%, 94.4% and 80% respectively. On CE-MRC, biliary excretion was seen in only 60.87% anastomoses and only these were taken for analysis. The sensitivity, specificity, PPV and NPV of CE-MRC for the diagnosis of anastomotic stricture were 40%, 75%, 80% and 33.3%. The combined evaluation of T2W-MRCP and CE-MRC showed sensitivity, specificity, PPV and NPV of 83.3%, 80%, 93.8% and 57.1%.

CONCLUSION

At present, T2W-MRCP is still the diagnostic modality of choice in the evaluation of patients with BEA stricture and the usage of Gd-BOPTA enhanced MRC is inappropriate in this setting.

Hepatobiliary scintigraphy for the assessment of biliary strictures after pediatric liver transplantation

HBS is used in the management of liver transplantation, a significant complication of which is biliary stricture. Strictures may be intraparenchymal within segments and main duct (non-anastomotic) or at the biliary-enteric anastomosis (anastomotic). Strictures are definitively diagnosed, and often managed, by PTC. This is invasive, technically challenging, and requires general anesthesia in young children. HBS may allow early detection of these complications and is non-invasive. The aim of this study was to review the scintigraphic pattern of biliary strictures using (99m)TcDISIDA HBS following pediatric orthotopic liver transplantation, and to assess its role in the diagnostic algorithm of suspected biliary strictures. All available hepatobiliary studies performed post-transplant in 101 episodes of liver transplantation in 92 pediatric patients were reviewed. Twenty-three (23%) patients had known biliary strictures. Twenty-two patients had adequate studies available for review; five had intrahepatic (non-anastomotic) strictures alone, nine had a stricture of the anastomosis alone, and eight had both intrahepatic and anastomotic strictures. HBS patterns (either segmental or global changes) correlated very highly with clinically significant biliary strictures. All patients with known strictures had abnormal HBS; hence, in patients with abnormal liver function tests post-liver transplant, a normal HBS makes strictures very unlikely. We propose that HBS can thus be used to determine if further investigation is required.

Bile leakage after living donor liver transplantation demonstrated with hepatobiliary scan using 9mTc-PMT

Although it is recognized that hepatobiliary scan is of value in assessing postoperative complications of biliary surgery or cadaveric whole liver transplantation, there have been few reports regarding its usefulness following living donor liver transplantation. We performed living donor liver transplantation in a patient with biliary cirrhosis due to hepatolithiasis, using a right lobe graft from her sister. On the 15th postoperative day, bile discharge appeared from the operative wound. The leakage point could not be identified by computed tomography and cholangiography from the biliary drainage catheter. Hepatobiliary scan with Tc-99m Sn-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) demonstrated biliary extravasation from the left side of the anastomosis of the hepatico-jejunostomy, indicating biliary leakage from the anastomosis. Conservative therapy was continued because the radioisotope flowed smoothly into the reconstructed jejunum and the biliary drainage catheter, and the leakage was stopped on the 63th postoperative day. Hepatobiliary scan is useful in determining the therapeutic plan as well as detection of bile leakage and identification of leakage points after living donor liver transplantation.

Preoperative assessment of liver function: a comparison of 99mTc-Mebrofenin scintigraphy with indocyanine green clearance test

BACKGROUND/AIMS

The indocyanine green (ICG) clearance test is the most frequently used test for preoperative assessment of liver parenchymal function but has its limitations. The aim of this study was to investigate the correlation between ICG clearance test and the liver uptake of 99-Technetium-labelled (99mTc)-Mebrofenin (99mTc-Mebrofenin) as measured with hepatobiliary scintigraphy.

METHODS

Fifty-four patients were diagnosed as hepatocellular carcinoma (n=9), hilar tumours (n=20) and 25 patients with non-parenchymal tumours including colorectal metastasis (n=15) and miscellaneous tumours (n=10). One day prior to operation, hepatobiliary 99mTc-Mebrofenin scintigraphy was performed after intravenous injection of 85 MBq and the 15-min clearance rate of ICG (ICG-C15) was measured.

RESULTS

The mean ICG-C15 was 86.86+/-1.19% (SEM). The mean 99mTc-Mebrofenin uptake rate was 12.87+/-0.52%/min. A significant correlation was obtained between 99mTc-Mebrofenin uptake rate by scintigraphy and ICG-C15 (r=0.73, P<0.0001). The mean clearance capacity of the right liver segments (79.83+/-1.63, range 47.75-95.97%) was larger than that of the left segments (20.24+/-1.55, range 6.51-52.51%).

CONCLUSION

99mTc-Mebrofenin uptake rate as assessed by scintigraphy is an efficient method for determining liver function and correlates well with ICG clearance. At the same time, 99mTc-Mebrofenin scintigraphy provides information of segmental functional liver tissue, which is of additional use when planning liver resection.