Hepatobiliary scintigraphy in liver transplant patients: the "blind end sign" and its differentiation from bile leak

Hepatobiliary scintigraphy with SPECT/CT

Hepatobiliary scintigraphy with single-photon emission computed tomography (SPECT) is an essential Nuclear Medicine exam for assessing hepatobiliary abnormalities and planning therapy. We aim to offer a thorough and all-encompassing analysis of hepatobiliary imaging with SPECT to emphasize the practicality, precision in diagnosis, surgical or transplant planning, and advanced uses of SPECT/CT in assessing hepatobiliary disease. Readers can anticipate acquiring a comprehensive understanding of the subsequent facets. The manuscript will explore in detail the diverse clinical uses of SPECT/CT imaging in hepatobiliary system, recent technological breakthroughs in SPECT/CT imaging techniques, specifically addressing quantitative analysis methodologies, and the integration of SPECT/CT with other imaging modalities. This article will provide readers with information on current research trends and future prospects in SPECT/CT imaging for hepatobiliary applications, such as strategies for monitoring therapy, the use of artificial intelligence and machine learning for quantitative imaging biomarkers, how these advanced techniques influence patient care, treatment choices, and prognostic predictions. The goal of the review is to help the readers acquire useful knowledge about the latest hepatobiliary SPECT/CT imaging, their clinical applications, and their prospective contribution to the advancement.

Imaging complications of liver transplantation: a multimodality pictorial review

Liver transplantation is one of the most commonly performed surgical procedures for the treatment of end-stage liver disease and hepatocellular carcinoma. Post-transplantation complications include vascular, nonvascular, and biliary. Common imaging techniques used to evaluate the hepatic graft are ultrasonography (US), CT, MR imaging, cholangiography, angiography, and scintigraphy. The purposes of this pictorial review are to review imaging findings of complications of liver transplantation and provide a framework for early detection of post-surgical complications.

Imaging of post-operative pancreas and complications after pancreatic adenocarcinoma resection

Pancreatic ductal adenocarcinoma is one of the leading causes of cancer-related deaths. With surgical resection being the only definitive treatment, improvements in technique has led to an increase in number of candidates undergoing resection by inclusion of borderline resectable disease patients to the clearly resectable group. Post-operative complications associated with pancreaticoduodenectomy and distal pancreatectomy include delayed gastric emptying, anastomotic failures, fistula formation, strictures, abscess, infarction, etc. The utility of dual-phase CT with multiplanar reconstruction and 3D rendering is increasingly recognized as a tool for the assessment of complications associated with vascular resection and reconstruction such as hemorrhage, pseudoaneurysm, vascular thrombosis, and ischemia. Prompt recognition of the complications and distinction from benign post-operative findings such as hepatic steatosis and mesenteric fat necrosis on imaging plays a key role in helping decrease the morbidity and mortality associated with surgery. We discuss, with case examples, some of such common and uncommon findings on imaging to familiarize the abdominal radiologists evaluating post-operative imaging in both acute and chronic post-operative settings.

Utility of hepatobiliary scintigraphy for recurrent reflux cholangitis following choledochojejunostomy: A case report

INTRODUCTION

Reflux cholangitis is a frequent complication of Roux-en-Y choledochojejunostomy.

PRESENTATION OF CASE

A 68-year-old male underwent left lobectomy of the liver, bile duct resection and choledochojejunostomy for intrahepatic cholangiocarcinoma located in Segment 2 of the liver, 40mm in diameter with a lymph node metastasis 5 years ago. He had frequent recurrences of postoperative reflux cholangitis and hepatic abscesses and was treated with antibiotics each time. Postoperative adjuvant chemotherapy was scheduled, but due to recurrent cholangitis it was difficult. Although double balloon endoscopy for endoscopic retrograde cholangiography was performed, no stenosis was found in the choledochojejunostomy anastomosis, and no defect suspected of calculus and stenosis were found by contrast. Antibiotics had to be administered for a long time because it recurred when antibiotics were discontinued. This time, a tumor 2.0cm in diameter was detected in segment 7 of the liver on follow - up computed tomography. The preoperative diagnosis was recurrent Intrahepatic cholangiocarcinoma. Hepatobiliary scintigraphy was carried out in preparation for concomitant treatment of his reflux cholangitis. Retention in the blind loop of the choledochojejunostomy was retarded, and the excretion was delayed. Therefore, hepatectomy and resection of the blind loop were performed. We confirmed improvement of stasis in the blind loop on postoperative hepatobiliary scintigraphy. The postoperative course was uneventful, and antibiotics were not required.

DISCUSSION

Hepatobiliary scintigraphy may be able to clarify the mechanism underlying reflux cholangitis.

CONCLUSION

Hepatobiliary scintigraphy was useful for the treatment of recurrent reflux cholangitis in this case.

Recurrent cholangitis by biliary stasis due to non-obstructive afferent loop syndrome after pylorus-preserving pancreatoduodenectomy: report of a case

We report a 71-year-old man who had undergone pylorus-preserving pancreatoduodenectomy (PPPD) using PPPD-IV reconstruction for cholangiocarcinoma. For 6 years thereafter, he had suffered recurrent cholangitis, and also a right liver abscess (S5/8), which required percutaneous drainage at 9 years after PPPD. At 16 years after PPPD, he had been admitted to the other hospital because of acute purulent cholangitis. Although medical treatment resolved the cholangitis, the patient was referred to our hospital because of dilatation of the intrahepatic biliary duct (B2). Peroral double-balloon enteroscopy revealed that the diameter of the hepaticojejunostomy anastomosis was 12 mm, and cholangiography detected intrahepatic stones. Lithotripsy was performed using a basket catheter. At 1 year after lithotripsy procedure, the patient is doing well. Hepatobiliary scintigraphy at 60 minutes after intravenous injection demonstrated that deposit of the tracer still remained in the upper afferent loop jejunum. Therefore, we considered that the recurrent cholangitis, liver abscess, and intrahepatic lithiasis have been caused by biliary stasis due to nonobstructive afferent loop syndrome. Biliary retention due to nonobstructive afferent loop syndrome may cause recurrent cholangitis or liver abscess after hepaticojejunostomy, and double-balloon enteroscopy and hepatobiliary scintigraphy are useful for the diagnosis of nonobstructive afferent loop syndrome.

Added value of SPECT/CT over planar Tc-99m mebrofenin hepatobiliary scintigraphy in the evaluation of bile leaks

OBJECTIVE

To determine the added value of single-photon emission computed tomography/computed tomography (SPECT/CT) over planar hepatobiliary scintigraphy (HBS) in suspected cases of bile leak.

MATERIALS AND METHODS

An analysis of the data of all patients who had undergone HBS for suspected bile leak during the last 3 years was carried out. All patients had undergone an initial 45 min dynamic study after an intravenous injection of Tc-99m mebrofenin, following which they underwent multiple static imaging studies for up to 24 h and SPECT/CT imaging whenever needed.

RESULTS

A total of 203 patients had undergone an HBS for evaluation of a suspected bile leak. HBS was positive for bile leak in 110 patients, among whom 42 had undergone additional SPECT/CT. In 32 patients SPECT/CT was useful in (i) defining the exact location of collection [intracapsular vs. extracapsular vs. intraparenchymal leak (n=18/25)], (ii) defining the extent of intraparenchymal collections (n=6/6), (iii) characterizing large abdominal collections (n=2/2), and (iv) characterizing suspected contamination (n=4/4), (v) suspected collection (n=0/3), (vi) and other miscellaneous conditions (n=2/2). Defining the extent and exact localization of collection can have therapeutic implications such as the accurate site of placement of the drain for drainage. In approximately one-third of the bile leak-positive HBS studies (32/110), SPECT/CT images were helpful for better characterization of biliary collection. In all, 76% (32/42) of the SPECT/CT studies were found to provide additional useful information over planar imaging.

CONCLUSION

Hybrid SPECT/CT offers the unique advantage of combining the anatomical information from CT with the functional information provided by HBS. It is most useful in characterization of biliary collections, which give important scintigraphic evidence of the severity of bile leak with therapeutic implications such as placement of a drain or surgical exploration.

Intestinal malrotation in adult seen on hepatobiliary scintigraphy

Hepatobiliary scintigraphy is primarily used to diagnose acute and chronic biliary tract disorders. However, its potential role in diagnosing unsuspected extrahepatic pathology is not well described. We present 2 adult patients with chronic abdominal pain who underwent hepatobiliary scintigraphy for evaluation of cystic duct patency. In both cases, the proximal small bowel was located on the right side of the abdomen, which suggested the diagnosis of malrotation. Retrospective review of abdominal CT scan, upper gastrointestinal series, and subsequent laparotomy confirmed malrotation. The diagnosis of malrotation in both these patients was first suggested on hepatobiliary scintigraphy, which significantly impacted their subsequent management.

Demonstration of a perihepatic abscess communicating with a fistula from the small bowel on hepatobiliary imaging

Abscess formation after abdominal surgery is not an uncommon complication. It is much less common for a collection to be the result of a fistulous tract from the bowel. We describe a patient who underwent a Tc-99m hepatobiliary (Choletec) scan for the workup of a perihepatic abscess, which confirmed the presence of a fistulous tract from the small bowel to a perihepatic collection.