Radionuclide imaging of hepatic and biliary disease

Cholestasis in the Baby and Infant

Cholestasis in children is a serious condition due to various aetiologic factors. If children with jaundice present with acholic stool, dark urine colour, or direct hyperbilirubinaemia, the patient should be evaluated urgently. Early and timely diagnosis and initiation of appropriate treatment are extremely important determinants of morbidity and mortality. In the neonatal period, idiopathic neonatal cholestasis, alpha-1 antitrypsin deficiency, cholestasis from infections, and biliary atresia are the most common causes of cholestasis. Nowadays, with the development of genetic and molecular biological studies, the diagnosis of many diseases that have previously been evaluated as ‘idiopathic‘ can be made. It is the aetiological factor that determines the prognosis. The treatment plan is created in accordance with aetiological causes and in response to symptoms such as pruritus and malabsorption: this can be surgical treatment across a diverse spectrum, from biliary diversion to liver transplantation. In this study, the aetiology, diagnosis, and treatment of cholestasis in babies and infants are reviewed in the light of current literature.

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.

Nuclear imaging of the liver: is there a diagnostic role of HIDA in posttransplantation?

BACKGROUND AND AIMS

Biliary complications are common after liver transplantation. This study sought to assess the value of hepatic iminodiacetic acid (HIDA) scans (hepatobiliary iminodiacetic acid scan) to detect early posttransplantation biliary complications.

METHODS

From April 2003 to June 2006, 34 liver transplantations (recipients of mean +/- SD age of 43.0 +/- 15.7 years) were performed in 25 (73.5%) males from 20 (58.8%) cadaveric donors and 14 (41.2%) living-related donors. The subjects underwent HIDA scans using a single head gamma camera Meridian (Philips) after intravenous (IV) administration of 185 MBq Tc-99m Disofenin. The mean time +/- SD posttransplantation to HIDA scan was 14.6 +/- 18.2 days (range, 0-74). The results were compared with endoscopic retrograde cholangio pancreatography, magnetic resonant cholangiopancreatography, percutaneous cholangiograhy, and/or liver biopsy.

RESULTS

Twenty-four abnormalities were detected by HIDA scan in 16 patients (47.1%): 10 (29.4%) biliary leaks; 4 (11.4%) biliary obstruction or cholestasis; 1 (2.9%) delayed uptake; 5 (14.7%) delayed blood pool clearance; and 8 (23.5%) delayed transit to the bowel. The complications were more common among living-donor compared with deceased-donor graft recipients, albeit a not statistically significant difference (P = .066). Total and direct bilirubin levels were significantly higher in patients with abnormal than normal HIDA scans (P = .011 and P = .040, respectively). The sensitivity and specificity of HIDA scans to detect overall postoperative complications were 100% and 66.7%, respectively. Biliary leak results were false positives in 7/10 patients, and true in 3. Detection of obstruction was 75% sensitive by HIDA.

CONCLUSION

HIDA scans are a noninvasive, reliable modality for early exclusion of posttransplantation biliary complications. However, correlation with clinical status and imaging modalities is essential to confirm detected abnormalities.

Tc-99m ciprofloxacin imaging in acute cholecystitis

AIM: To evaluate the efficacy of a new nuclear imaging Infecton (Tc-99m ciprofloxacin) for the diagnosis of acute cholecystitis.

METHODS: Sixteen patients thought to have acute cholecystitis were included in this study. The diagnosis of acute cholecystitis was made based on clinical symptoms and ultrasonographic and pathologic findings.

RESULTS: The 16 patients were composed of 12 acute and 4 chronic cholecystitis patients. Twelve patients with acute cholecystitis were image-positive, including one false-positive. Four patients with chronic cholecystitis were image-negative, of whom three were true-negative. This nuclear imaging had a sensitivity of 91.7%, a specificity of 75%, a positive-predictive value of 91.7%, and a negative-predictive value of 75%.

CONCLUSION: Tc-99m ciprofloxacin imaging is easy to perform and applicable for the diagnosis of acute cholecystitis.

Biliary dyskinesia in pediatrics

Biliary dyskinesia is a potential cause for acalculous biliary colic in pediatric patients. A triad of symptoms and signs, consisting of abdominal pain (with or without associated nausea or fatty food intolerance), absence of gallstones, and an abnormally low cholecystokinin-stimulated gallbladder ejection fraction is used to diagnose the disorder. In several small pediatric case series, cholecystectomy resulted in symptomatic improvement in a majority of patients with biliary dyskinesia. However, the diagnosis of biliary dyskinesia and appropriate management remain controversial. This review discusses the purported pathophysiology of biliary dyskinesia and the data available regarding diagnosis and treatment of this entity in the pediatric population.

Neonatal cholestasis

Any infant who is jaundiced beyond two to three weeks of life should be evaluated for neonatal cholestasis. Neonatal cholestasis is defined as accumulation of bile substances in blood due to impaired excretion. These infants should always have fractionated serum bilirubin levels checked to differentiate the conjugated hyperbilirubinemia of cholestasis from unconjugated hyperbilirubinemia that is usually benign and spontaneously resolves. Conjugated hyperbilirubinemia, pale stools and dark urine are the cardinal features of neonatal cholestasis. The differential diagnosis of cholestasis is extensive and a systematic approach is helpful to quickly establish the diagnosis. Biliary atresia is a common cause of neonatal cholestasis and affected infants need surgery before 60 days of life for better prognosis. Premature infants have multifactorial cholestasis and need a modified approach to the evaluation of cholestasis. Management of cholestasis is mostly supportive, consisting of medical management of complications of chronic cholestasis like pruritus and nutritional support for malabsorption and vitamin deficiency.

Hepatic imaging. An overview

For optimal detection and characterization of focal or diffuse liver disease, it is essential to obtain the most appropriate imaging test in the correct clinical setting. Access to clinical information and medical history is, therefore, essential. Moreover, familiarity with currently available modalities for imaging the liver [figure: see text] allows the optimal use of the technical advances in ultrasound imaging, CT scanning, MR imaging, and nuclear scintigraphy technology and contributes to improved diagnostic accuracy.