Hepatobiliary scintigraphy in children

[Is the alpps procedure justified in children?]

The authors have analyzed the indications and outcomes after ALPPS procedure considering modern literature data devoted to this surgery in pediatric patients. No data on post-resection liver failure, as well as unclear future liver remnant function make it possible to question the feasibility of such procedures in children.

Tc-99m PMT scintigraphy in the diagnosis of pediatric biliary atresia

PURPOSE

Hepatobiliary scintigraphy plays an important role in the differentiation of biliary atresia (BA) and non-BA. The usefulness of ^99mTc-iminodiacetic acid (IDA) derivatives in BA diagnosis is reported in several papers. In contrast, there are no comprehensive data on differentiating BA from non-BA using ^99mTc-N-pyridoxyl-5-methyl-tryptophan (PMT). Our objective was to evaluate the usefulness of ^99mTc-PMT scintigraphy in the diagnosis of BA.

MATERIALS AND METHODS

52 infants who received ^99mTc-PMT scintigraphy for suspected BA were retrospectively evaluated. Preoperative cholangiograms or follow-ups were used as the gold standard for diagnosis of BA. We analyzed the utility of ^99mTc-PMT scintigraphy, various clinical and investigational parameters in the diagnosis of BA.

RESULTS

The final diagnoses in this group were BA (67.3%) and non-BA (32.7%). ^99mTc-PMT scintigraphy, stool color change, total bilirubin, direct bilirubin, aspartate aminotransferase (AST) and γ-glutamyl transferase (γ-GTP) led to distinguishing between BA and non-BA in univariate analysis. Subsequent multivariate logistic regression analysis indicated that ^99mTc-PMT scintigraphy and γ-GTP were independent predictors of BA. The diagnostic accuracy of ^99mTc-PMT scintigraphy was 94.2%.

CONCLUSIONS

^99mTc-PMT scintigraphy is more accurate in the diagnosis of BA than other conventional examinations. In addition, false positives of ^99mTc-PMT scintigraphy could be reduced by combining γ-GTP level monitoring.

Synthesis and Biocompatibility Studies of New Iminodiacetic Acid Derivatives

BACKGROUND

Iminodiacetic acid (IDA) derivatives can be used as ligands to form complexes with technetium, with potential application as hepatobiliary diagnostic agents. The aim of this study was to synthesize five novel IDA derivatives and to compare their effects on plasma haemostasis with clinically approved ligands for technetium complexation.

METHODS

The influence of synthesized IDA derivatives on plasma haemostasis was evaluated spectrophotometrically by clot formation and lysis test (CL-test), coagulation assay, Prothrombin Time and Activated Partial Tromboplastin Time. The effects of the tested compounds on erythrocytes were assessed using haemolysis assays, microscopy and flow cytometry studies.

RESULTS

Despite their significant influence on the kinetic parameters of the process of clot formation and fibrinolysis, the tested ligands, at potential diagnostic concentrations, did not alter the overall potential of clot formation and lysis (CLAUC). At potential diagnostic concentrations (0.4 μmol/mL) all the tested compounds showed no adverse effects on the membranes of RBCs (Red Blood Cells).

CONCLUSION

IDA derivatives with methoxy substituents in aromatic ring, exert multidirectional effects on plasma haemostasis and should be considered safe as their significant impacts were mostly observed at 4 μmol/mL, which is about 10-fold higher than the theoretical plasma concentrations of these compounds.

Tc-99m mebrofenin hepatobiliary scan in obstructive hepatobiliary disease: determining causes with early and late delayed imaging

Hepatobiliary radionuclide imaging is typically performed to detect cholecystitis. Infrequently, imaging reveals an obstructive pattern. Although delayed hepatobiliary imaging is commonly used to differentiate between intrahepatic (IH) and extrahepatic (EH) obstruction in the newborn; there is room to clarify the use of delayed imaging in the adult population. A retrospective review was performed of adult patients demonstrating a complete obstructive pattern on initial Tc-99m mebrofenin hepatobiliary imaging. Delayed imaging was divided into early delayed (ED) (<10 h) and late delayed (LD) (≥10 h) imaging. Two physicians qualified the presence of intestinal radiotracer (negative, low to high) on delayed images. Determination of EH or IH pathology was obtained from chart review. A total of 24 patients demonstrated an obstructive pattern using delayed Tc-99m mebrofenin hepatobiliary imaging, with delayed imaging ranging from 4 to 30 h. EH pathologies (choledocholithiasis, stricture, other) represented 63% of cases (n = 15), IH pathologies (cirrhosis, hepatitis, other) represented 33% cases (n = 8) and 1 case was indeterminate. 67% of EH cases showed intestinal activity on delayed imaging (67% on ED and 67% on LD imaging), whereas 63% of IH cases showed intestinal activity on delayed imaging (67% on ED imaging and 60% on LD imaging). The presence of intestinal activity on the both the early and delayed images did not differentiate between the IH and EH pathology groups. Subdividing the groups into ED imaging and LD imaging was also not predictive of determining location of obstructive pattern on the initial 1 h of imaging. This data suggests that delayed hepatobiliary scintigraphy has little or no role in determining the cause of obstructive pathology.

Functional hepatobiliary MR imaging in children

BACKGROUND

Clinical application efforts for the hepatocyte-specific MRI contrast agent gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) have mainly been directed toward detection and characterization of various hepatic masses in the adult population.

OBJECTIVE

Here we report our initial experience with Gd-EOB-DTPA for evaluating congenital and acquired hepatobiliary pathologies in the pediatric population.

MATERIALS AND METHODS

Twenty-one consecutive children receiving Gd-EOB-DTPA for functional hepatobiliary evaluation at our institution were retrospectively identified with IRB approval. The use of Gd-EOB-DTPA was classified in each case as definite, potential, or no clinical utility, focusing on the clinical value gained beyond traditional noncontrast fluid-sensitive MR cholangiopancreatography (FS-MRCP) and other imaging modalities.

RESULTS

Definite added value of Gd-EOB-DTPA was found in 12 patients, with potential value in 4 patients, and no value in 5 patients. Benefit was seen in cases of iatrogenic and non-iatrogenic biliary strictures, perihepatic fluid collections for biliary leak, hepatobiliary dysfunction in the absence of hyperbilirubinemia, and in the functional exclusion of cystic duct occlusion that can be seen in acute cholecystitis.

CONCLUSION

This is the first reported series of children with Gd-EOB-DTPA and this early work suggests potential pediatric applications.

The value of radionuclide hepatobiliary scintigraphy in combination with determination of bilirubin from duodenal drainage in differential diagnosis of infantile persistent jaundice

The aim of this study was to investigate the value of technetium etifenin injection (99mTc-EHIDA) hepatobiliary scintigraphy in combination with determination of bilirubin from duodenal drainage in differential diagnosis between infantile hepatitis syndrome and biliary atresia. 99mTc-EHIDA hepatobiliary scintigraphy in combination with duodenal fluid examination was used for evaluation in 84 infants with persistent infantile jaundice. For diagnosing biliary atresia, the sensitivity and specificity of scintigraphy were 100% and 74.5%, respectively; the sensitivity and specificity of scintigraphy in combination with duodenal fluid examination were 100% and 100%, respectively. In conclusion, hepatobiliary scintigraphy, which is a noninvasive, safe, valuable examination method, in combination with examination of duodenal fluid, is of value for the differential diagnosis between infantile hepatitis syndrome and biliary atresia.

Comparison of different diagnostic methods for differentiating biliary atresia from idiopathic neonatal hepatitis

AIM

To retrospectively analyze different methods in differentiating biliary atresia from idiopathic neonatal hepatitis.

METHODS

Sixty-nine infants with cholestatic jaundice and final diagnosis of idiopathic neonatal hepatitis (INH) and biliary atresia (BA) were studied retroprospectively from January 2004 to December 2006. A thorough history and physical examination were undertaken. All cases underwent abdominal magnetic resonance cholangiography (MRCP), ultrasonography (US), hepatobiliary scintigraphy (HBS), HBS single-photon emission computer tomography (HBS SPECT), and operation or percutaneous liver biopsy. The accuracy, sensitivity, specificity, and predictive values of these various methods were compared.

RESULTS

There were 39 girls and 30 boys, among whom 35 had INH (age, 61+/-17 days) and 34 had BA (age, 64+/-18 days). The mean age at onset of jaundice was significantly lower in cases of BA when compared to INH cases (9+/-13 vs. 20+/-21 days; P=.032). The diagnostic accuracy of different methods was as follows: liver biopsy, 97.1%; HBS SPECT, 91.30%; MRCP, 71.01%; HBS, 66.67%; US, 65.22%.

CONCLUSION

Our results indicate that biopsy of the liver is considered as the most reliable method to differentiate INH from BA. The accuracy of HBS SPECT is higher than that of MRCP, HBS, and US. There was no significant difference in diagnostic accuracy among MRCP, HBS, and US.

Pediatric MR cholangiopancreatography: principles, technique, and clinical applications

High-quality magnetic resonance (MR) cholangiopancreatographic images are difficult to obtain in children due to the small caliber of the pediatric bile ducts and to motion artifacts. However, there has been ongoing improvement in image quality, thanks to better coil technology, increased speed of acquisition, refinement in respiratory compensation techniques, and newer sequences. Heavily T2-weighted fast spin-echo (FSE) and single-shot FSE MR imaging sequences with long echo times are used to image the biliary and pancreatic ducts. Secretin has been shown to improve the visualization of the pancreatic duct and pancreaticobiliary junction. Factors that affect image quality in pediatric MR cholangiopancreatography include sedation, negative oral contrast material, radiofrequency coil selection, respiratory compensation techniques, echo time, echo train length, section-slab thickness, planes of scanning, field of view, and number of signals acquired. However, giving proper attention to these factors and tailoring the study to the body size of the patient (which varies considerably) can lead to high-quality diagnostic MR cholangiopancreatographic images. Use of MR cholangiopancreatography in children is limited by the need for sedation or anesthesia, high cost, limited availability, and long scanning times. Nonetheless, this modality can be a viable alternative to endoscopic retrograde cholangiopancreatography (ERCP) in the evaluation of various entities such as choledochal cyst, recurrent pancreatitis, primary sclerosing cholangitis, and a transplanted liver, and may obviate ERCP.

Biliary atresia: recent progress

Extrahepatic biliary atresia (EHBA), an inflammatory sclerosing cholangiopathy, is the leading indication for liver transplantation in children. The cause is still unknown, although possible infectious, genetic, and immunologic etiologies have received much recent focus. These theories are often dependent on each other for secondary or coexisting mechanisms. Concern for EHBA is raised by a cholestatic infant, but the differential diagnosis is large and the path to diagnosis remains varied. Current treatment is surgical with an overall survival rate of approximately 90%. The goals of this article are to review the important clinical aspects of EHBA and to highlight some of the more recent scientific and clinical developments contributing to our understanding of this condition.

Pediatric Gastrointestinal Nuclear Medicine

General localization of gastrointestinal bleeding through the use of labeled red blood cells may be performed in children, or (99m)Tc-pertechnetate may be used if a Meckel's diverticulum is suspected. As in adults, cholecystitis and biliary leak may be assessed in children via (99m)Tc-IDA derivatives. Gastroesophageal reflux can be evaluated by oral consumption of the child's usual diet labeled with (99m)Tc sulfur colloid. For the scintigraphic determination of pulmonary aspiration, a relatively high concentration of tracer within a drop of liquid is placed beneath the child's tongue followed by dynamic imaging of the respiratory tract. Colonic transit scintigraphy can aid in the identification and therapeutic decision-making in patients with functional fecal retention, the most common cause of chronic constipation in children. (18)F-DOPA positron emission tomography is useful for classifying pancreatic involvement in infantile hyperinsulinism as focal or diffuse, thereby differentiating between patients who should receive curative focal pancreatic resection versus those who should receive medical management. Assessment of protein-losing enteropathy can be conducted scintigraphically and, compared with fecal alpha-1 antitrypsin collection, the scintigraphic method can detect esophageal and gastric protein loss. Also, scintigraphic quantification of protein loss can be performed without the requirement for fecal collection. Intestinal inflammation in children with inflammatory bowel disease can be evaluated using (99m)Tc white blood cells. The scintigraphic method is safe, accurate, well-tolerated by children and complementary to endoscopy in most patients.

Hepatobiliary Scintigraphy With SPECT in Infancy

Hepatobiliary scintigraphy (HBS) is an important investigation for the diagnosis of biliary atresia (BA) and its differentiation from causes of conjugated hyperbilirubinemia that do not require surgical intervention. Delayed imaging at 24 hours and phenobarbitone augmentation for 5 days has been required to achieve high sensitivity and specificity with current techniques. This study explores whether adding single photon emission computed tomography (SPECT) performs as well as existing methods without requiring delayed 24-hour imaging and whether the phenobarbitone premedication is necessary in all cases.

METHODS

A retrospective analysis of 105 HBS studies on 94 patients was performed. HBS included SPECT at 4 to 6 hours postinjection when no tracer was seen in the gastrointestinal tract in the first 60 minutes. This was done in 80 patients.

RESULTS

Gastrointestinal activity was seen in 14 patients within 60 minutes. For 4- to 6-hour studies, standard HBS and HBS with SPECT data showed a sensitivity of 100% for the diagnosis of BA. The specificity, accuracy, and positive likelihood ratios (PLR) were 67%, 75%, and 3 (confidence interval [CI]=2.03-4.16) for planar imaging at 4 to 6 hours and 90%, 93%, and 10 (CI=4.42-19) for 4- to 6-hour planar and SPECT imaging. When the 11 patients who had phenobarbitone stimulation were included, the results improved to 97%, 98%, and 30 (CI=7.06-80).

CONCLUSION

The addition of SPECT 4 to 6 hours postinjection of tracer significantly improves the diagnostic accuracy of hepatobiliary scintigraphy compared with planar imaging alone. This accuracy is as good as HBS performed after phenobarbitone stimulation. The combined technique of HBS with SPECT and phenobarbitone has the highest accuracy. Delayed imaging at 24 hours is usually not necessary.

Comparison of different diagnostic methods in infants with Cholestasis

AIM: To evaluate different methods in differentiating idiopathic neonatal hepatitis from biliary atresia.

METHODS: Sixty-five infants with cholestatic jaundice and final diagnosis of idiopathic neonatal hepatitis and biliary atresia were studied prospectively from September 2003 to March 2006. A thorough history and physical examination were undertaken and the liver enzymes were examined. All cases underwent abdominal ultrasonography, hepatobiliary scintigraphy, and percutaneous liver biopsy. The accuracy, sensitivity, specificity and predictive values of these various methods were compared.

RESULTS: There were 34 girls and 31 boys, among them 46 subjects had idiopathic neonatal hepatitis (age, 61 ± 17 d) and 19 had biliary atresia (age, 64 ± 18 d). The mean age at onset of jaundice was significantly lower in cases of biliary atresia when compared to idiopathic neonatal hepatitis cases (9 ± 13 d vs 20 ± 21 d; P = 0.032). The diagnostic accuracy of different methods was as follows: liver biopsy, 96.9%; clinical evaluation, 70.8%; ultrasonography, 69.2%; hepatobiliary scintigraphy, 58.5%; and liver enzymes, 50.8%.

CONCLUSION: Our results indicate that clinical evaluation by an experienced pediatric hepatologist and a biopsy of the liver are considered as the most reliable methods to differentiate idiopathic neonatal hepatitis and biliary atresia.

Hepato-biliary Scintigraphy in diagnosis of Biliary Atresia

BACKGROUND

Biliary Atresia and Neonatal Hepatitis are the two major causes of Persistent Neonatal Jaundice. Differentiation is done by biochemical and radiological tests. Radiological investigations use intra-or extra-hepatic biliary dilation for diagnosing biliary atresia but this is not always reliable.

METHODS

14 neonates with persistent conjugated hyperbilirubinemia who had undergone hepato-biliary scintigraphy were retrospectively evaluated and those having Extrahepatic Biliary Atresia were analyzed with reference to operative findings.

RESULTS

11 out of 14 had Extrahepatic Biliary Atresia during operation whereas 3 proved to be false positive.

CONCLUSION

Mebrofenin hepato - biliary scintigraphy is a simple, safe, accurate and cost effective investigation for diagnosis of biliary atresia.

A child with undifferentiated sarcoma of the liver complicated with bronchobiliary fistula and detected by hepatobiliary scintigraphy

Undifferentiated (embryonal) sarcoma of the liver (USL) is a rare malignant mesenchymal tumor principally affecting patients of pediatric age. Bronchobiliary fistula is a very rare complication in patients with liver tumor. To the authors' knowledge, this is the first report of a bronchobiliary fistula resulting from tumor invasion in a child with liver sarcoma. A 12-year-old boy was diagnosed to have USL of the right liver lobe, invading the diaphragm. An extended right hepatectomy and total resection of the mass was performed, leaving patchy tumoral invasion of the anterior diaphragmatic surface followed by combined chemotherapy regimen. Six months after the operation, the presence of bilious sputum suggested a bronchobiliary fistula, which was confirmed by hepatobiliary scintigraphy. The patient underwent a right thoracotomy and fistula division. Although bronchobiliary fistula is a very rare complication in patients with hepatic tumors, suspicion in the appropriate clinical setting is necessary to recognize this problem. Hepatobiliary scintigraphy is the useful diagnostic procedure to define bronchobiliary fistula in children with liver tumor and clinical suspicion of bronchobiliary fistula.

Nonoperative management of blunt extrahepatic biliary duct transection in the pediatric patient: case report and review of the literature

An 11-year-old boy sustained a grade IV liver injury and complete disruption of the left hepatic duct (LHD) secondary to a sledding accident. Although he became hemodynamically stable after initial resuscitation in the emergency department and the intensive care unit (ICU), serial paracentesis procedures were necessary to manage abdominal compartment syndrome (ACS). The fluid initially was serosanguinous but subsequently became bile stained. A bile leak was confirmed by a technetium 99m dimethyliminodiacetic acid (HIDA) scan and an endoscopic retrograde cholangiogram (ERCP). The LHD transection was treated with percutaneous drainage of the subhepatic space and a transampullary biliary stent. The leak sealed within 8 days, and follow-up ERCP as an outpatient showed no extravasation but could not visualize the LHD. Repeat computed tomography (CT) scan 3(1/2) months after injury showed the liver laceration to be healed with atrophy of the left lobe and no ductal dilatation. The patient has had a complete recovery, resumed all activities, and currently is 20 months after his injury with no sequelae.

Pharmacologic interventions in nuclear radiology: indications, imaging protocols, and clinical results

Nuclear radiology is valuable in assessing pathophysiology of a variety of organ systems. Pharmacologic interventions are often employed in radionuclide imaging to monitor the physiologic changes, which in turn facilitate the diagnosis. Metoclopramide, erythromycin, and cisapride have been used for gastric emptying studies. To overcome false-negative results, cimetidine, pentagastrin, and glucagon have been used in imaging of Meckel diverticula. Pharmacologic intervention with either cholecystokinin-8 or morphine is used primarily for the assessment of diseases of the gallbladder, common bile duct, and sphincter of Oddi. Pharmacologic interventions performed during renography include diuretic administration, angiotensin-converting enzyme inhibition, and aspirin renography. Recombinant thyrotropin can be used in patients with previously treated thyroid carcinoma who require lifelong follow-up for recurrent disease. Cardiac pharmacologic stress agents fall into two categories: coronary vasodilating agents, such as dipyridamole and adenosine, and cardiac positive inotropic agents, such as dobutamine and arbutamine. Measurement of hemodynamic responses to pharmacologic flow augmentation with carbon dioxide or acetazolamide is valuable in cerebrovascular perfusion studies.

The effects of HDV-insulin on carbohydrate metabolism in Type 1 diabetic patients

The aim of this study was to compare the metabolic effects of a single equimolar subcutaneous injection of hepatic directed vesicle-insulin (HDV-insulin) and regular insulin on glucose levels and intermediary metabolism during a 75-g oral glucose tolerance test (OGTT). Nine Type 1 diabetic patients underwent two experiments separated by 4 weeks. Each experimental protocol consisted of an identical evening meal followed by overnight euglycemic control achieved by a continuous low-dose insulin infusion. The next morning a subcutaneous injection (0.1 U/kg) of HDV-insulin or regular insulin was administered 30 min before a 75-g OGTT. The overnight basal insulin infusion was maintained unaltered throughout the 150-min OGTT. Plasma glucose, glucoregulatory hormones (insulin, glucagon, cortisol), and intermediary metabolites (lactate, alanine, glycerol, NEFA, beta-hydroxybutyrate) were measured to assess the metabolic effects of the two insulin preparations. Compared to regular insulin, an equivalent subcutaneous dose of HDV-insulin significantly lowered glucose levels during OGTT (mean reduction 2.2+/-0.4 mmol/l; P<.005). Plasma levels of insulin and glucagon were equivalent during both series of experiments. Blood lactate, glycerol and plasma NEFA levels were not different during OGTT indicating similar peripheral action of the insulins. beta-Hydroxybutyrate levels were significantly reduced (P<.05) following HDV-insulin supporting a preferential hepatic action of the preparation. We conclude that HDV-insulin can significantly lower plasma glucose excursions compared to an equivalent dose of regular insulin during an OGTT in Type 1 diabetic patients. The metabolic profile of equivalent peripheral insulin, glucagon and glycerol levels but reduced beta-hydroxybutyrate values support a hepatospecific effect of HDV-insulin.

Long-term prospective study of the effect of ursodeoxycholic acid on cystic fibrosis-related liver disease

GOALS

To evaluate the efficacy of UDCA in arresting the progression of the early multifocal hepatic lesion to overt CF-related NBC.

BACKGROUND

Focal biliary cirrhosis is an early hepatic pathologic change related to the ion transport defect in cystic fibrosis. The factors involved in the progression of focal to nodular biliary cirrhosis are not clear. Ursodeoxycholic--a hydrophilic, nontoxic, choleretic, and hepatoprotective exogenous bile acid--has been reported to be effective in the management of cholestatic liver disease.

STUDY

For 10 years at 6-month intervals, 70 individuals with cystic fibrosis (38 men and 32 women; age range, 2--29 years) were examined using hepatosplenomegaly, liver function tests, and ultrasound liver scan. Patients demonstrating evidence of liver involvement at the onset or during the study received ursodeoxycholic acid 20 mg/kg body weight.

RESULTS

After the administration of ursodeoxycholic acid, the progression of nodular biliary cirrhosis ultrasound changes was arrested, hepatic function was preserved, and no variceal bleeding was observed. No case of focal biliary cirrhosis progressed to nodular biliary cirrhosis. Furthermore, the multifocal, multilobular changes suggestive of focal biliary cirrhosis on ultrasound scan were reversed to normal.

CONCLUSION

Ursodeoxycholic acid is effective in improving cholestasis and hepatic dysfunction in nodular biliary cirrhosis and, also, in reversing the early sonography findings suggestive of focal biliary cirrhosis. It is speculated that ursodeoxycholic acid may prove to affect the natural history of cystic fibrosis-related liver disease.

Classifying choledochal cysts using hepatobiliary scintigraphy

PURPOSE

This retrospective study was designed to classify choledochal cysts on the basis of the findings of hepatobiliary scintigraphy.

METHODS

Twenty-one patients with choledochal cysts (15 female, 6 male; mean age, 20 years) proved on the findings of endoscopic retrograde cholangiopancreatography (ERCP) or surgery and histopathologic analysis were included in the study. Two nuclear medicine physicians, blinded with regard to cholangiographic and operative details, were asked to review and to classify the type of choledochal cyst seen on the hepatobiliary scan. Later, scintigraphic results were compared with ERCP and surgical findings for a reference standard.

RESULTS

The findings of hepatobiliary scintigraphy correlated with ERCP and surgical findings in 18 of 21 cases (86%). Scintiscans correctly identified all type 1 cysts (12/12). The sensitivity of scintigraphy in diagnosing type 4 cysts was 66% (6 of 9 cases). It underestimated the intrahepatic extent of disease in type 4a biliary cysts (37%).

CONCLUSION

This study illustrates the utility of hepatobiliary scintigraphy in diagnosing type 1 and 4 choledochal cysts.

[Hepatobiliary scintigraphy in a case of acute cholecystitis in childhood]

Acute cholecystitis is an uncommon disease in childhood. Few cases in patients under 10 years of age have been found in literature. An eight-year old male patient with no history of interest who had acute acalculous cholecystitis was reported. Ultrasonographic and isotopic studies led to the diagnosis and control of the patient's evolution.

The use of hepatocyte extraction fraction to evaluate neonatal cholestasis

PURPOSE

Hepatobiliary scintigraphy is used routinely to evaluate infants with neonatal cholestasis. Hepatobiliary scintigraphy determines biliary patency by detecting radioactivity in the bowel on imaging, in duodenal and gastric aspirates, or all of these. During hepatobiliary scintigraphy, the hepatocyte extraction fraction (HEF) is calculated by deconvolution analysis. Normal values of HEF are more than 90%. It is believed that HEF may predict hepatic dysfunction, because, during hepatobiliary scintigraphy, the radiopharmaceutical used in this test is extracted by the hepatocytes from the blood stream. Therefore, a low value of HEF is seen with more severe hepatocellular disease. The goal of this study was to determine whether HEF has any correlation with synthetic liver function, whether HEF can differentiate obstructive from nonobstructive lesions that cause neonatal cholestasis, and whether HEF can predict the outcome of the different causes of neonatal cholestasis.

METHODS

A retrospective analysis of 68 hepatobiliary scintigraphy results was done in patients with neonatal cholestasis for a period covering 6 years.

RESULTS

The HEF was available in 67 of these 68 patients, with a median value of 25% (range, 3.3% to 100%). The results of synthetic liver function tests (i.e., albumin and prothrombin time) were normal in all infants with neonatal cholestasis. No significant correlation was detected between HEF and the serum levels of total and direct bilirubin, albumin, alkaline phosphatase, and prothrombin time by exploratory data analysis (R = 0.08; small, P > 0.2). The HEF values in different causes of neonatal cholestasis were compared: extrahepatic biliary atresia, neonatal hepatitis, and a miscellaneous category consisting of alpha1-antitrypsin deficiency, ischemic hepatitis, paucity of bile ducts, and others. The outcomes of these diseases were assessed as resolution, continuing disease, transplantation, or death, but no predictive correlation was found with HEF.

CONCLUSIONS

A single determination of HEF is of no value in assessing synthetic liver function (as assessed by albumin and prothrombin time), specific diagnoses, and outcomes in patients with neonatal cholestasis. Therefore, a low isolated value of HEF should not be considered suggestive of poor prognosis and outcome in these patients.

MR cholangiography in the evaluation of neonatal cholestasis

PURPOSE

To evaluate the usefulness of magnetic resonance (MR) cholangiography in excluding biliary atresia as the cause of neonatal cholestasis.

MATERIALS AND METHODS

MR cholangiography was performed on 10 control and 16 jaundiced neonates and infants aged 3 days to 5 months. Diagnosis of biliary atresia (n = 6) was confirmed with surgery and liver biopsy, with or without surgical cholangiography. Diagnosis of neonatal hepatitis (n = 9) was confirmed with clinical follow-up until jaundice resolved. In one infant, paucity of intrahepatic ducts was diagnosed at liver biopsy. MR cholangiography was performed with respiratory-triggered, heavily T2-weighted turbo spin-echo and optional inversion-recovery turbo spin-echo sequences. Diagnosis of biliary atresia was based on nonvisualization of either the common bile duct or common hepatic duct. Cholescintigraphy with technetium 99m disofenin was performed in all 16 jaundiced patients.

RESULTS

In the 10 controls, the nine patients with neonatal hepatitis, and the one infant with paucity of intrahepatic ducts, MR cholangiography clearly depicted the gallbladder and common hepatic and common bile ducts. MR cholangiography was 100% accurate in excluding biliary atresia as the cause of neonatal cholestasis, while 99mTc disofenin cholescintigraphic findings were false-positive in four of 10 patients with nonobstructive cholestasis.

CONCLUSION

MR cholangiography can be used to depict the major biliary structures of neonates and small infants and to exclude biliary atresia as the cause of neonatal cholestasis by allowing visualization of the biliary tract.