The porta hepatis microcyst: an additional sonographic sign for the diagnosis of biliary atresia

Comparison for the diagnostic performance of early diagnostic methods for biliary atresia: a systematic review and network meta-analysis

BACKGROUND

Biliary atresia (BA), a progressive condition affecting canalicular-bile duct function/anatomy, requires prompt surgical intervention for favorable outcomes. Therefore, we conducted a network meta-analysis of common diagnostic methods to assess their performance and provide evidence-based support for clinical decision-making.

METHODS

We reviewed literature in PubMed, EMBASE, and Cochrane for BA diagnostics. The search included gamma-glutamyl transferase (GGT), direct/combined bilirubin, matrix metalloproteinase 7 (MMP-7), ultrasonic triangular cord sign (TCS), hepatic scintigraphy (HS), and percutaneous cholangiocholangiography/percutaneous transhepatic cholecysto-cholangiography (PCC/PTCC). QUADAS-2 assessed study quality. Heterogeneity and threshold effect were evaluated using I2 and Spearman's correlation. We combined effect estimates, constructed SROC models, and conducted a network meta-analysis based on the ANOVA model, along with meta-regression and subgroup analysis, to obtain precise diagnostic performance assessments for BA.

RESULTS

A total of 40 studies were included in our analysis. GGT demonstrated high diagnostic accuracy for BA with a sensitivity of 81.5% (95% CI 0.792-0.836) and specificity of 72.1% (95% CI 0.693-0.748). Direct bilirubin/conjugated bilirubin showed a sensitivity of 87.6% (95% CI 0.833-0.911) but lower specificity of 59.4% (95% CI 0.549-0.638). MMP-7 exhibited a total sensitivity of 91.5% (95% CI 0.893-0.934) and a specificity of 84.3% (95% CI 0.820-0.863). TCS exhibited a sensitivity of 58.1% (95% CI 0.549-0.613) and high specificity of 92.9% (95% CI 0.911-0.944). HS had a high sensitivity of 98.4% (95% CI 0.968-0.994) and moderate specificity of 79.0% (95% CI 0.762-0.816). PCC/PTCC exhibited excellent diagnostic performance with a sensitivity of 100% (95% CI 0.900-1.000) and specificity of 87.0% (95% CI 0.767-0.939). Based on the ANOVA model, the network meta-analysis revealed that MMP-7 ranked second overall, with PCC/PTCC ranking first, both exhibiting superior diagnostic accuracy compared to other techniques. Our analysis showed no significant bias in most methodologies, but MMP-7 and hepatobiliary scintigraphy exhibited biases, with p values of 0.023 and 0.002, respectively.

CONCLUSION

MMP-7 and ultrasound-guided PCC/PTCC show diagnostic potential in the early diagnosis of BA, but their clinical application is restricted due to practical limitations. Currently, the cutoff value of MMP-7 is unclear, and further evidence-based medical research is needed to firmly establish its diagnostic value. Until more evidence is available, MMP-7 is not suitable for widespread diagnostic use. Therefore, considering cost and operational simplicity, liver function tests combined with ultrasound remain the most clinically valuable non-invasive diagnostic methods for BA.

[Developmental disorders of the gastrointestinal tract]

BACKGROUND

Developmental disorders of the gastrointestinal tract comprise a broad spectrum of congenital malformations of different etiologies and locations from the mouth to the anus.

METHODS

The authors present the most important malformations of the gastrointestinal tract on the basis of basic and current reviews.

RESULTS

Gastrointestinal developmental disorders occur both sporadically and in connection with malformation syndromes. Symptoms are highly variable and range from postnatal emergencies to asymptomatic abnormalities, which may be incidental radiological findings. Prenatal ultrasound examinations can often identify gastrointestinal developmental disorders at an early stage. Here, fetal magnetic resonance imaging can be a useful addition to the diagnostic process. In the first few days of life, simple X‑ray overview images, supplemented by images after the administration of contrast medium, are often sufficient.

CONCLUSION

Many patients with a malformation of the gastrointestinal tract require lifelong medical care, so that not only pediatric radiologists need specific knowledge about this group of diseases.

Diseases of bile duct in children

Several diseases originate from bile duct pathology. Despite studies on these diseases, certain etiologies of some of them still cannot be concluded. The most common disease of the bile duct in newborns is biliary atresia, whose prognosis varies according to the age of surgical correction. Other diseases such as Alagille syndrome, inspissated bile duct syndrome, and choledochal cysts are also time-sensitive because they can cause severe liver damage due to obstruction. The majority of these diseases present with cholestatic jaundice in the newborn or infant period, which is quite difficult to differentiate regarding clinical acumen and initial investigations. Intraoperative cholangiography is potentially necessary to make an accurate diagnosis, and further treatment will be performed synchronously or planned as findings suggest. This article provides a concise review of bile duct diseases, with interesting cases.

Preoperative imaging findings to predict 2-year native liver survival after the Kasai procedure in patients with biliary atresia

OBJECTIVES

To investigate the feasibility of using preoperative imaging indices to predict 2-year native liver survival after the Kasai procedure in patients with biliary atresia (BA).

MATERIALS AND METHODS

The retrospective review included 190 BA patients who underwent the Kasai procedure between 2000 and 2020, with preoperative US and/or MRI, excluding cases with less than 2-year follow-up period. Multivariable logistic regression analysis was performed to identify imaging indices to predict 2-year native liver survival. Kasai failure was defined as the need for liver transplantation or death within 2 years of the Kasai procedure.

RESULTS

Of the 90 patients included, all had preoperative US, and 61 also had MRI. Kasai failure occurred in 52% (47/90). Preoperative US identified gallbladder length (OR 0.40, 95% CI 0.17-0.95, p = 0.039; cutoff 1.6 cm, AUC 67.66) and biliary cysts (OR 24.64, 95% CI 1.97-308.08, p = 0.013) as significant Kasai failure predictors, with a combined accuracy of 73% (60/82). For patients having both preoperative US and MRI, significant predictors were hepatic artery diameter (OR 6.75, 95% CI 1.31-34.88, p = 0.023; cutoff 2 mm, AUC 73.83) and biliary cysts (OR 23.89, 95% CI 1.43-398.82, p = 0.027) on US, and gallbladder length (OR 0.25, 95% CI 0.08-0.76, p = 0.014; cutoff 1.2 cm, AUC 74.72) and spleen size (OR 2.53, 95% CI 1.02-6.29, p = 0.045; cutoff 6.9 cm, AUC 73.72) on MRI, with a combined accuracy of 85% (52/61).

CONCLUSION

Preoperative US and/or MRI enhance the 2-year native liver survival prediction in BA patients after the Kasai procedure.

CLINICAL RELEVANCE STATEMENT

BA patients with hepatic artery diameter > 2 mm (US), gallbladder length < 1.6 cm (US) or < 1.2 cm (MRI), spleen size > 6.9 cm (MRI), and absence of biliary cysts (US/MRI) have a decreased likelihood of 2-year native liver survival.

KEY POINTS

• Preoperative US and/or MRI can predict the probability of achieving 2-year native liver survival following the Kasai procedure. • Combining US and MRI improved the accuracy to 85% for predicting 2-year native liver survival in BA patients. • The hepatic artery diameter > 2 mm (US), gallbladder length < 1.6 cm (US) or < 1.2 cm (MRI), spleen size > 6.9 cm (MRI), and no biliary cysts (US/MRI) are significant predictors of Kasai failure in patients with biliary atresia.

Interpretable artificial intelligence-based app assists inexperienced radiologists in diagnosing biliary atresia from sonographic gallbladder images

BACKGROUND

A previously trained deep learning-based smartphone app provides an artificial intelligence solution to help diagnose biliary atresia from sonographic gallbladder images, but it might be impractical to launch it in real clinical settings. This study aimed to redevelop a new model using original sonographic images and their derived smartphone photos and then test the new model's performance in assisting radiologists with different experiences to detect biliary atresia in real-world mimic settings.

METHODS

A new model was first trained retrospectively using 3659 original sonographic gallbladder images and their derived 51,226 smartphone photos and tested on 11,410 external validation smartphone photos. Afterward, the new model was tested in 333 prospectively collected sonographic gallbladder videos from 207 infants by 14 inexperienced radiologists (9 juniors and 5 seniors) and 4 experienced pediatric radiologists in real-world mimic settings. Diagnostic performance was expressed as the area under the receiver operating characteristic curve (AUC).

RESULTS

The new model outperformed the previously published model in diagnosing BA on the external validation set (AUC 0.924 vs 0.908, P = 0.004) with higher consistency (kappa value 0.708 vs 0.609). When tested in real-world mimic settings using 333 sonographic gallbladder videos, the new model performed comparable to experienced pediatric radiologists (average AUC 0.860 vs 0.876) and outperformed junior radiologists (average AUC 0.838 vs 0.773) and senior radiologists (average AUC 0.829 vs 0.749). Furthermore, the new model could aid both junior and senior radiologists to improve their diagnostic performances, with the average AUC increasing from 0.773 to 0.835 for junior radiologists and from 0.749 to 0.805 for senior radiologists.

CONCLUSIONS

The interpretable app-based model showed robust and satisfactory performance in diagnosing biliary atresia, and it could aid radiologists with limited experiences to improve their diagnostic performances in real-world mimic settings.

Development and validation of a model for early diagnosis of biliary atresia

BACKGROUND AND AIMS

Early diagnosis of biliary atresia (BA), particularly distinguishing it from other causes of neonatal cholestasis (NC), is challenging. This study aimed to design and validate a predictive model for BA by using the data available at the initial presentation.

METHODS

Infants presenting with NC were retrospectively identified from tertiary referral hospitals and constituted the model design cohort (n = 148); others were enrolled in a prospective observational study and constituted the validation cohort (n = 21). Clinical, laboratory, and abdominal ultrasonographic features associated with BA were assessed. A prediction model was developed using logistic regression and decision tree (DT) analyses.

RESULTS

Three predictors, namely, gamma glutamyl transpeptidase (γGT) level, triangular cord sign (TC sign), and gallbladder abnormalities, were identified as factors for diagnosing BA in multivariate logistic regression, which was used to develop the DT model. The area under the receiver operating characteristic (ROC) curve (AUC) value for the model was 0.905, which was greater than those for γGT level, TC sign, or gallbladder abnormalities alone in the prediction of BA.

CONCLUSION

A simple prediction model combining liver function and abdominal ultrasonography findings can provide a moderate and early estimate of the risk of BA in patients with NC.

Anomalies of the fetal gallbladder: pre-and postnatal correlations

The gallbladder is not part of the standard survey of a fetus during obstetrical ultrasound. Yet, some anomalies can be detected. Most are clinically benign, but some are features of or associated with more serious complications. Biliary atresia constitutes the diagnosis with the worst prognosis. Its in utero diagnosis is difficult. Still, markers do exist and should be searched for. Knowledge of the normal appearances, variants and abnormalities of the gallbladder contributes to proper management. Any suspicion should lead to meticulous postnatal workup. Pre- or postnatal magnetic resonance imaging can provide additional information in select cases.

Gamma-Glutamyl Transferase Combined With Conventional Ultrasound Features in Diagnosing Biliary Atresia: A Two-Center Retrospective Analysis

OBJECTIVES

To develop and validate a biliary atresia (BA) diagnostic score based on serum gamma-glutamyl transferase (GGT) levels and conventional ultrasound features for discriminating BA in patients with jaundice from two centers.

METHODS

A total of 958 patients from one hospital were classified as the derivation cohort, and 725 patients from another hospital were classified as the validation cohort. The optimal GGT cutoff value for diagnosing BA was calculated in the derivation cohort and subsequently verified in the validation cohort. Gallbladder abnormalities and the triangular cord (TC) sign were evaluated in all patients. A BA diagnostic score was developed for diagnosing BA using the GGT levels, gallbladder abnormalities and the TC sign based on the data from the derivation cohort followed by external validation.

RESULTS

Based on the optimal cutoff value 350.0 U/L, GGT yielded a sensitivity of 59.3% and specificity of 85.4% in diagnosing BA. The area under the receiver operating characteristic curve (AUC 0.724) was inferior to that of the gallbladder (AUC 0.911, P < .001) and comparable to that of the TC sign (AUC 0.771, P = .128). The combination of GGT and ultrasound diagnosis could help to reduce the misdiagnosis of 9 infants with BA. The BA diagnostic score yielded a sensitivity of 93.3% and specificity of 95.0% with the highest AUC in this study (0.941).

CONCLUSIONS

GGT can add diagnostic value to ultrasound examination when diagnosing BA. The BA diagnostic score based on GGT, gallbladder abnormalities and the TC sign shows satisfactory discrimination abilities in BA.

Percutaneous ultrasound-guided cholecystocholangiography with microbubbles combined with liver biopsy for the assessment of suspected biliary atresia

BACKGROUND

Percutaneous ultrasound (US)-guided cholecystocholangiography is effective in diagnosing biliary atresia for infants with a gallbladder >1.5 cm in length on US. However, whether it is still effective for other types of gallbladders needs further clarification.

OBJECTIVE

To evaluate the diagnostic performance and safety of percutaneous US-guided cholecystocholangiography combined with liver biopsy in children with suspected biliary atresia and with different types of gallbladders on US.

MATERIALS AND METHODS

Sixty-five infants were referred for percutaneous US-guided cholecystocholangiography with microbubbles and liver biopsy after an equivocal (n=39) or highly suspected (n=26) US diagnosis of biliary atresia. Two radiologists evaluated US and percutaneous US-guided cholecystocholangiography images in consensus. One pathologist independently evaluated liver specimens. We used the unpaired t-test, Mann-Whitney U test and chi-square test to analyze the data.

RESULTS

Of the 65 infants, 59 (90.8%) underwent a successful percutaneous US-guided cholecystocholangiography, with both sensitivity and specificity of 100%. All six infants for whom puncture failed had contracted gallbladders. The sensitivity and specificity of liver biopsy in the diagnosis of biliary atresia were 89.7% (26/29) and 83.3% (30/36), respectively. When percutaneous US-guided cholecystocholangiography and liver biopsy were combined, all infants gained correct diagnosis, and in 35 infants (97.2%, 35/36) biliary atresia could be excluded without intraoperative cholangiography. Twenty-two of 65 infants (33.8%) had fluid collections around the liver related to puncture. None of these complications needed treatment.

CONCLUSION

Percutaneous US-guided cholecystocholangiography combined with liver biopsy appears safe and effective for excluding or confirming biliary atresia in cholestatic infants with a dilated gallbladder on US.

Neonatal diagnosis of biliary atresia: a practical review and update

Biliary atresia is challenging to diagnose because many of the clinical and imaging features of this condition overlap with those of other causes of cholestasis in newborns. When jaundice persists beyond 2 weeks of age, the neonate should be evaluated for cholestasis, and biliary atresia - the most common cause of neonatal cholestasis - should be considered. It is critical to diagnose biliary atresia early because failure to treat can result in hepatic fibrosis and death in less than 1 year. In this paper, we review the current diagnostic imaging methods, differential considerations and treatment options for biliary atresia.

Diagnostic approach to neonatal and infantile cholestasis: A position paper by the SIGENP liver disease working group

Neonatal and infantile cholestasis (NIC) can represent the onset of a surgically correctable disease and of a genetic or metabolic disorder worthy of medical treatment. Timely recognition of NIC and identification of the underlying etiology are paramount to improve outcomes. Upon invitation by the Italian National Institute of Health (ISS), an expert working grouped was formed to formulate evidence-based positions on current knowledge about the diagnosis of NIC. A systematic literature search was conducted to collect evidence about epidemiology, etiology, clinical aspects and accuracy of available diagnostic tests in NIC. Evidence was scored using the GRADE system. All recommendations were approved by a panel of experts upon agreement of at least 75% of the members. The final document was approved by all the panel components. This position document summarizes the collected statements and defines the best-evidence diagnostic approach to cholestasis in the first year of life.

Ultrasound for the Diagnosis of Biliary Atresia: From Conventional Ultrasound to Artificial Intelligence

Biliary atresia is an aggressive liver disease of infancy and can cause death without timely surgical intervention. Early diagnosis of biliary atresia is critical to the recovery of bile drainage and long-term transplant-free survival. Ultrasound is recommended as the initial imaging strategy for the diagnosis of biliary atresia. Numerous ultrasound features have been proved helpful for the diagnosis of biliary atresia. In recent years, with the help of new technologies such as elastography ultrasound, contrast-enhanced ultrasound and artificial intelligence, the diagnostic performance of ultrasound has been significantly improved. In this review, various ultrasound features in the diagnosis of biliary atresia are summarized. A diagnostic decision flow chart for biliary atresia is proposed on the basis of the hybrid technologies, combining conventional ultrasound, elastography and contrast-enhanced ultrasound. In addition, the application of artificial intelligence in the diagnosis of biliary atresia with ultrasound images is also introduced.

Latest diagnostic performance of different ultrasonic features for biliary atresia

BACKGROUND

Early diagnosis of biliary atresia (BA) is an important clinical challenge.

PURPOSE

To summarize the latest diagnostic performance of different ultrasonic (US) features for BA.

MATERIAL AND METHODS

MeSH terms "biliary atresia" and "ultrasonography" and related hyponyms were used to search PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. Eligible articles were included and data were retrieved. The methodologic quality was assessed by version 2 of the Quality Assessment of Diagnostic Accuracy Studies tool. Estimated sensitivity and specificity of each US feature were calculated by Stata 14.0.

RESULTS

Fifty eligible studies on 5622 patients were included. Respective summary sensitivity and specificity were 77% (95% CI=69-84) and 98% (95% CI=96-99) for triangular cord sign (TCS) in 32 studies, 86% (95% CI=78-92) and 86% (95% CI=72-94) for shear wave elastography (SWE) in seven studies, 75% (95% CI=65-83) and 92% (95% CI=86-95) for gallbladder and biliary system abnormality (GBA) in 25 studies, and 81% (95% CI=69-90) and 79% (95% CI=67-87) for hepatic artery (HA) enlargement in seven studies. The overall US features from 11 studies yielded a summary sensitivity of 84% (95% CI=72-92) and specificity of 86% (95% CI=77-92).

CONCLUSION

TCS and GBA were the two most widely accepted US features currently used for differential diagnosis of BA. The newly developed SWE was an objective and convenient method with good diagnostic performance. HA enlargement can be used as an auxiliary sign.

Ultrasound characteristics combined with gamma-glutamyl transpeptidase for diagnosis of biliary atresia in infants less than 30 days

PURPOSE

To retrospectively assess the diagnostic performance of grey-scale ultrasound (US) characteristics and gamma-glutamyl transpeptidase (GGT) alone or combined in distinguishing biliary atresia (BA) from other cholestasis diseases in infants younger than 30 days.

MATERIALS AND METHODS

Between January 2012 and October 2020, the demographic characteristics, laboratory results and US characteristics of 35 BA and 52 non-BA infants younger than 30 days were retrospectively evaluated. Areas under the receiver operating characteristic curves (AUCs) were used to estimate the probability of predicting BA, which were compared by DeLong test.

RESULTS

The diagnostic performance of gallbladder classification in identifying BA was higher than that of fibrotic cord thickness (AUC 0.900 vs. 0.771, P = 0.03). With the cutoff level of 188 IU/L, serum GGT had a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 77.1%, 69.2%, 62.8%, and 81.8%, respectively. Combined with gallbladder classification and GGT, the sensitivity, specificity, PPV, NPV and accuracy were 100.0%, 63.5%, 64.8%, 100.0% and 78.2%.

CONCLUSIONS

Gallbladder classification was more valuable than fibrotic cord thickness in the diagnosis of BA among infants less than 30 days. Combined with gallbladder classification and GGT, the sensitivity for the diagnosis of BA can reach 100.0%.

The Prognosis of Type III Biliary Atresia with Hilar Cyst

OBJECTIVE

To compare the outcome of biliary atresia (BA) patients with and without hilar cyst on preoperative ultrasound.

METHODS

A single center retrospective review of patients of BA with (n = 27) and without hilar cyst (n = 27) over a 5 y period was done. The patients were analyzed using propensity score matching to reduce selection bias. All patients were diagnosed as type III BA by histologic examination and cholangiograms. Clinicopathological characteristics and survival outcomes were compared between the two groups.

RESULTS

There were no significant intergroup differences between baseline characteristics and outcomes after Kasai portoenterostomy surgery in two groups. BA with hilar cyst group showed comparable survival outcomes to the BA without cyst group (cumulative 1-y, 2-y and 5-y overall survival rates with native liver 61.4% vs. 65.8%, P = 0.041; 45.0% vs. 49.0%, P = 0.57; 45.0% vs. 49.0%, P = 0.57). And the Kaplan-Meier survival curves showed no significant difference in cumulative survival with native liver between the two groups (P = 0.58).

CONCLUSIONS

Type III BA with hilar cyst had no better prognosis compared with Type III BA without cyst.

Practical approach to imaging diagnosis of biliary atresia, Part 1: prenatal ultrasound and magnetic resonance imaging, and postnatal ultrasound

We present a practical approach to imaging in suspected biliary atresia, an inflammatory cholangiopathy of infancy resulting in progressive fibrosis and obliteration of extrahepatic and intrahepatic bile ducts. Left untreated or with failure of the Kasai procedure, biliary atresia progresses towards biliary cirrhosis, end-stage liver failure and death by age 3. Differentiation of biliary atresia from other nonsurgical causes of neonatal cholestasis is challenging because there is no single method for diagnosing biliary atresia, and clinical, laboratory and imaging features of this disease overlap with those of other causes of neonatal cholestasis. Concerning imaging, our systematic literature review shows that ultrasonography is the main tool for pre- and neonatal diagnosis. Key prenatal features, when present, are non-visualisation of the gallbladder, cyst in the liver hilum, heterotaxy syndrome and irregular gallbladder walls. Postnatal imaging features have a very high specificity when present, but a variable sensitivity. Triangular cord sign and abnormal gallbladder have the highest sensitivity and specificity. The presence of macro- or microcyst or polysplenia syndrome is highly specific but less sensitive. The diameter of the hepatic artery and hepatic subcapsular flow are less reliable. When present in the context of acholic stools, dilated intrahepatic bile ducts rule out biliary atresia. Importantly, a normal US exam does not rule out biliary atresia. Signs of chronic hepatopathy and portal hypertension (portosystemic derivations such as patent ductus venosus, recanalised umbilical vein, splenomegaly and ascites) should be actively identified for - but are not specific for - biliary atresia.

Key imaging features for differentiating cystic biliary atresia from choledochal cyst: prenatal ultrasonography and postnatal ultrasonography and MRI

Purpose

This study compared clinical and radiologic differences between cystic biliary atresia (cBA) and choledochal cyst (CC) type Ia/b.

Methods

Infants (≤12 months old) who were diagnosed with cBA or CC type Ia/b from 2005 to 2019 were retrospectively reviewed. Imaging features on preoperative ultrasonography (US) and magnetic resonance imaging (MRI) were compared between the cBA and CC groups. Logistic regression and area under the receiver operating characteristic curve (AUC) analyses were performed for the diagnosis of cBA. Changes in cyst size were also evaluated when prenatal US exams were available.

Results

Ten patients (5.5% of biliary atresia cases) with cBA (median age, 48 days) and 11 infants with CC type Ia/b (Ia:Ib=10:1; median age, 20 days) were included. Triangular cord thickness on US (cutoff, 4 mm) showed 100% sensitivity and 90.9% specificity (AUC, 0.964; 95% confidence interval [CI], 0.779 to 1.000) and cyst size on MRI (cutoff, 2.2 cm) had 70% sensitivity and 100% specificity (AUC, 0.900; 95% CI, 0.690 to 0.987) for diagnosing cBA. Gallbladder mucosal irregularity on US and an invisible distal common bile duct on MRI were only seen in the cBA group (10 of 10). Only the CC group showed prenatal cysts exceeding 1 cm with postnatal enlargement.

Conclusion

Small cyst size (<1 cm) on prenatal US, triangular cord thickening (≥4 mm) and gallbladder mucosal irregularity on postnatal US, and small cyst size (≤2.2 cm) and an invisible distal common bile duct on MRI can discriminate cBA from CC type Ia/b in infancy.

Three-color risk stratification for improving the diagnostic accuracy for biliary atresia

OBJECTIVES

It is challenging to early differentiate biliary atresia from other causes of cholestasis. We aimed to develop an algorithm with risk stratification to distinguish biliary atresia from infantile cholestasis.

METHODS

In this study, we enrolled infants with cholestasis into 2 subgroups from January 2010 to April 2019. A prospective cohort (subgroup 2) of 187 patients (107 with biliary atresia and 80 without biliary atresia) underwent acoustic radiation force impulse elastography. Stepwise regression was used to identify significant predictors of biliary atresia. A sequential algorithm with risk stratification was constructed.

RESULTS

Among 187 patients, shear wave speed > 1.35 m/s and presence of the triangular cord sign were considered high risk for biliary atresia (red), in which 73 of 78 patients (accuracy of 93.6%) with biliary atresia were identified. Afterwards, γ-GT, abnormal gallbladder, and clay stool were introduced into the algorithm and 55 intermediate-risk infants were identified (yellow) with a diagnostic accuracy of 60% for biliary atresia. Of the remaining 54 infants who were classified as low-risk patients (green), the accuracy for excluding biliary atresia was 98.1%. By applying a three-color risk stratification tool, 70.6% patients were identified as either high risk or low risk for biliary atresia (area under the curve, 0.983; sensitivity, 98.7%; specificity, 91.4%). We also estimated the risk of biliary atresia in different color groups, which was 94.7% (95%CI, 94.3-95.5%) in the red group and 7.2% (95%CI, 6.6-8.3%) in the green group.

CONCLUSIONS

Our simple noninvasive approach was able to identify biliary atresia with high accuracy.

KEY POINTS

• Five predictors, namely shear wave speed, triangle cord sign, γ-glutamyl transferase, abnormal gallbladder, and clay stool, were selected to identify biliary atresia in cholestasis. • Shear wave speed > 1.35 m/s and presence of the triangle cord sign were considered high-risk patients with a diagnostic accuracy of 93.6% for biliary atresia. • Risk for biliary atresia was high (red), intermediate (yellow), or low (green). In the red and green group, we achieved an extremely high diagnostic performance (area under the curve, 0.983; sensitivity, 98.7%; specificity, 91.4%).

Ultrasound Evaluation of Biliary Atresia Based on Gallbladder Classification: Is 4 Hours of Fasting Necessary?

OBJECTIVES

The aim of this study was to evaluate the influence of fasting time on the ultrasound identification and exclusion of biliary atresia in jaundiced infants through the use of the gallbladder classification scheme and to test the value of the gallbladder classification scheme in the diagnosis of biliary atresia in inexperienced individuals.

METHODS

A total of 188 jaundiced infants were enrolled in this study. All patients received detailed abdominal sonograms. Diagnoses were confirmed via liver biopsy, surgical findings, or follow-up. Infants were grouped into either the fasting group (fasting time ≥ 4 h) or the nonfasting group (fasting time < 4 h). According to the gallbladder classification scheme, the gallbladders were classified into 4 types. The accuracy of diagnosing biliary atresia based on the gallbladder classification scheme was compared between the 2 groups. The gallbladders of 177 infants that were detectable by ultrasonography were used to compare the diagnostic performances between a junior radiologist and an experienced radiologist.

RESULTS

The accuracies in the diagnosis of biliary atresia with the gallbladder classification scheme were 86.3% (82 of 95 patients) for the fasting group and 93.5% (87 of 93 patients) for the nonfasting group (P = .100). The diagnostic accuracies of biliary atresia were 88.7% (157 of 177 patients) for the junior radiologist and 90.4% (160 of 177 patients) for the experienced radiologist (P = .250). The κ value for the agreement between the 2 radiologists was 0.859.

CONCLUSIONS

The performance of gallbladder diagnoses was not influenced by the fasting time with the use of the gallbladder classification scheme. Additionally, the gallbladder classification scheme may help junior radiologists to more effectively identify biliary atresia and nonbiliary atresia.

Neonatal Jaundice

Hyperbilirubinemia is a common occurrence in neonates; it may be physiological or pathological. Conjugated hyperbilirubinemia may result from medical or surgical causes, and can result in irreversible liver damage if untreated. The aim of imaging is the timely diagnosis of surgical conditions like biliary atresia and choledochal cysts. Abdominal ultrasound is the first line imaging modality, and Magnetic resonance cholangiopancreatography (MRCP) also has a role, especially in pre-operative assessment of choledochal cysts (CDCs). For biliary atresia, the triangular cord sign and gallbladder abnormalities are the two most useful ultrasound features, with a combined sensitivity of 95%. Liver biopsy has an important role in pre-operative evaluation; however, the gold standard for diagnosis of biliary atresia remains an intra-operative cholangiogram. Choledochal cysts are classified into types according to the number, location, extent and morphology of the areas of cystic dilatation. They are often associated with an abnormal pancreaticobiliary junction, which is best assessed on MRCP. Caroli's disease or type 5 CDC comprises of multiple intrahepatic cysts. CDCs, though benign, require surgery as they may be associated with complications like cholelithiasis, cholangitis and development of malignancy. Severe unconjugated hyperbilirubinemia puts neonates at high risk of developing bilirubin induced brain injury, which may be acute or chronic. Magnetic resonance imaging of the brain is the preferred modality for evaluation, and shows characteristic involvement of the globus pallidi, subthalamic nuclei and cerebellum - in acute cases, these areas show T1 hyperintensity, while chronic cases typically show hyperintensity on T2 weighted images.

Does Supersonic Shear Wave Elastography Help Differentiate Biliary Atresia from Other Causes of Cholestatic Hepatitis in Infants Less than 90 Days Old? Compared with Grey-Scale US

Purpose

To investigate the diagnostic performance of shear wave elastography (SWE) for measuring liver stiffness to identify and differentiate biliary atresia (BA) from cholestatic hepatitis in infants younger than 90 days.

Methods

A total of 138 infants younger than 90 days with cholestatic hepatitis were examined by SWE. The infants were subclassified into BA and nonbiliary atresia (non-BA) groups. Receiver operating characteristic (ROC) analysis was used to determine the sensitivity and specificity of hepatic Young's modulus measurements, the ultrasonic findings in the differential diagnosis of suspected BA, and the cut-off value to diagnose BA.

Results

In all infants with cholestatic hepatitis, the cut-off value of hepatic Young's modulus to differentiate the BA group from the non-BA group was 12.35 kPa and the area under the ROC curve (AUC) was 0.937, with a sensitivity of 84.3% and a specificity of 89.7%; nevertheless the AUC of the abnormal gallbladder (AbGB) was 0.940, with a sensitivity of 96.1% and a specificity of 92.0%. In the parallel test, triangular cord (TC) sign combined with AbGB had the best diagnostic performance and the AUC was 0.960, with a sensitivity of 100% and a specificity of 92.0%. In the serial test, SWE combined with AbGB achieved the best diagnostic performance; the AUC was 0.902, the sensitivity and specificity were 80.4% and 100%, respectively.

Conclusions

SWE could not only help differentiate BA from cholestatic hepatic diseases but also increase the diagnostic specificity when combined with grey-scale ultrasound in the serial test.