Sonographic diagnosis of biliary atresia in pediatric patients using the "triangular cord" sign versus gallbladder length and contraction

OBJECTIVE: A retrospective review was performed to evaluate the importance of the "triangular cord" sign in comparison with gallbladder length and contraction for the diagnosis of biliary atresia in pediatric patients. MATERIALS AND METHODS: Fifty-five fasting infants with cholestatic jaundice were examined on sonography. The examinations focused on the visualization of the triangular cord sign and assessment of gallbladder length and contraction. The diagnosis of neonatal hepatitis or of other causes of infantile cholestasis was made if symptom resolution occurred during follow-up. RESULTS: A triangular cord sign was found in 27 of 29 infants with biliary atresia and in one of 26 infants with neonatal hepatitis or other causes of infantile cholestasis. The diagnostic accuracy was 95%, sensitivity was 93%, and specificity was 96%. The gallbladder was thought to be abnormal if it was less than 1.5 cm long, was not detectable, or was detectable but had no lumen. The gallbladder was abnormal in 21 of 29 infants with biliary atresia, whereas it was abnormal in eight of 26 infants with neonatal hepatitis or other causes of infantile cholestasis. The diagnostic accuracy was 71%, sensitivity was 72%, and specificity was 69%. The gallbladder was detectable on sonography in 13 infants with biliary atresia and 26 infants with neonatal hepatitis or other causes of infantile cholestasis. Gallbladder contraction was not confirmed in 11 of 13 infants with biliary atresia and seven of 26 infants with neonatal hepatitis or other causes of infantile cholestasis. The diagnostic accuracy was 77%, sensitivity was 85%, and specificity was 73%. CONCLUSION: The triangular cord sign was a more useful sonographic finding for diagnosing biliary atresia than gallbladder length and contraction.     

Ultrasound features of the gall bladder in infants presenting with conjugated hyperbilirubinaemia

An initial investigation of 313 patients suggested that the ultrasound appearances of gall bladder shape and wall structure might be abnormal in infants with biliary atresia. These observations were then tested in a prospective study. In this study, 346 infants, aged 12 weeks or less, presenting with conjugated hyperbilirubinaemia underwent ultrasound scanning. The gall bladder was identified in 331, 60 of whom had biliary atresia. 11 of the 15 patients in whom the gall bladder was not seen had biliary atresia. Gall bladder shape was normal in 272 patients, 16 of whom had biliary atresia, and irregular in 59, 44 of whom had biliary atresia. The gall bladder wall was regular in 262 patients, 8 of whom had biliary atresia, and irregular in 69, 52 of whom had biliary atresia. Combining these findings gave a sensitivity of 90%, a specificity of 92.4%, a positive predictive value of 75.3%, a negative predictive value of 97.3% and an accuracy rate of 91.9% for ultrasound of the gall bladder in identification of biliary atresia.     

Biliary atresia: US diagnosis

PURPOSE: To evaluate prospectively the sensitivity of ultrasonography (US) in the diagnosis of biliary atresia (BA), with surgery as the reference standard. MATERIALS AND METHODS: After institutional ethical approval and with informed parental consent, 90 consecutive fasting infants with conjugated hyperbilirubinemia underwent detailed US studies performed by a single operator with a 7.5-MHz curvilinear transducer and a 13.5-MHz linear-array transducer. The following features were prospectively recorded: gallbladder morphology, triangular cord sign, presence of a common bile duct, liver size and echotexture, splenic appearance, and vascular anatomy. The operator was blinded to results of other investigations. Sensitivity, specificity, and positive and negative predictive values were calculated for each US variable. BA and non-BA groups were compared by means of the Fisher exact test for categorical variables and an unpaired t test for continuous variables. RESULTS: Thirty infants (13 male, 17 female) had surgically confirmed BA, and 60 (35 male, 25 female) had other documented causes of neonatal jaundice; the mean ages at US assessment were 48.5 and 52.4 days, respectively (P>.5). Eight US features showed a significant difference between BA and non-BA groups (P<.001, Fisher exact test). The features with the greatest individual sensitivity and specificity, respectively, in the diagnosis of BA were triangular cord sign (73% and 100%), abnormal gallbladder wall (91% and 95%) and shape (70% and 100%), and an absent common bile duct (93% and 92%). The hepatic artery diameter was significantly larger in infants with BA than in those without BA (mean+/-standard deviation, 2.2 mm+/-0.59 vs 1.6 mm+/-0.40, P<.001), but portal vein diameters were not significantly different. By means of all these US features, 88 of 90 infants were correctly classified as having or not having BA, for an overall accuracy of 98%. CONCLUSION: BA can be distinguished with US from other causes of conjugated hyperbilirubinemia in 98% of infants if multiple US features are carefully evaluated.     

Biliary atresia: feasibility of mangafodipir trisodium-enhanced MR cholangiography for evaluation

The study was approved by the institutional review board, and informed consent was obtained from the patients' parents. Twenty-three consecutive infants suspected of having biliary atresia (BA) were prospectively examined by using mangafodipir trisodium (Mn-DPDP)-enhanced magnetic resonance (MR) cholangiography. Sequential T1-weighted spoiled gradient-echo MR cholangiograms were obtained 1, 2, and 3 hours after intravenous administration of Mn-DPDP. The possibility of BA was excluded if bowel excretion of contrast material was noted at contrast material-enhanced MR cholangiography. The diagnostic specificity and accuracy of contrast-enhanced MR cholangiography were compared with those of conventional MR cholangiography, technetium 99m Tc ((99m)Tc)-disofenin (DISIDA) scintigraphy, and the triangular cord sign at ultrasonography (US). MR cholangiography was used to accurately distinguish four cases of BA from 19 cases of other cholestatic liver diseases, without false-positive results. Conventional MR cholangiography, (99m)Tc-DISIDA scintigraphy, and the triangular cord sign at US respectively yielded false-positive results of 42% (eight of 19 infants), 35% (six of 17 infants), and 11% (two of 19 infants) in patients without BA. Mn-DPDP-enhanced MR cholangiography appears to be a promising modality for early diagnosis of BA as the cause of neonatal cholestasis.     

Hepatic arterial diameter measured with US: adjunct for US diagnosis of biliary atresia

PURPOSE: To prospectively evaluate the accuracy of hepatic artery diameter and hepatic artery diameter-to-portal vein diameter ratio for ultrasonographic (US) diagnosis of biliary atresia, with cholangiographic or clinical information as reference standard. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. US was performed in 68 neonates and infants with cholestatic jaundice (mean age, 61 days; male-to-female ratio, 38:30). Biliary atresia (n = 38) was confirmed with cholangiography, and hepatitis (n = 30) was diagnosed with clinical (n = 24) or cholangiographic (n = 6) findings. Diameter of the right hepatic artery was measured with US. Right hepatic artery diameter-to-right portal vein diameter ratio was measured to determine relative enlargement of the hepatic artery. As a control group, 17 neonates and infants (mean age, 67 days; male-to-female ratio, 12:5) without jaundice underwent US of the porta hepatis. Statistical analysis was performed to compare US parameters among three groups with one-way analysis of variance. Optimal cutoff values of the hepatic artery diameter and hepatic artery diameter-to-portal vein diameter ratio for biliary atresia diagnosis were obtained with receiver operating characteristic analysis. RESULTS: The diameter of the right hepatic artery in biliary atresia group (1.9 mm +/- 0.4 [standard deviation]) was significantly larger than that in the hepatitis (1.4 mm +/- 0.3) and control (1.2 mm +/- 0.2) groups (P < .001). Hepatic artery diameter-to-portal vein diameter ratio in the biliary atresia group (0.52 +/- 0.12) was larger than that in hepatitis (0.40 +/- 0.07) and in control (0.40 +/- 0.10) groups (P < .001). Optimum cutoff values for diagnosis of biliary atresia were 1.5 mm (sensitivity, 92%; specificity, 87%; accuracy, 89%) for hepatic artery diameter and 0.45 for hepatic artery diameter-to-portal vein diameter ratio (sensitivity, 76%; specificity, 79%; accuracy, 78%). CONCLUSION: Measurement of hepatic artery diameter can be helpful in the US diagnosis of biliary atresia.     

阴性法64层CT胆胰管成像在胆道闭锁中的诊断价值

目的：总结分析胆道闭锁的阴性法64层CT胆胰管成像（N—CTCP）的影像表现,探讨其诊断价值。方法：回顾性分析临床疑诊为胆道闭锁的52例患儿的影像资料,全部患儿行腹部增强CT门脉期扫描后采用容积重建（VR）、多平面重建（MPR）及最小密度投影（MinlP）等技术进行重建,观察并比较患儿肝内外胆道、肝门部结构、胆囊、肝脏、脾脏大小等征象的显示情况。结果：32例经手术病理证实为胆道闭锁（BA组）,20例临床确诊为婴儿肝炎综合征（IHS组）。胆道闭锁的N—CTCP影像特征包括：无或小胆囊、肝门区三角形低密度区、门静脉间隙增宽,可见“双边征”或“靶征”。BA组无1例显示胆总管,4例左、右肝管可见,但管道不连续,20例出现肝、脾肿大。小胆囊、三角征及门静脉间隙增宽在IHS组与BA组中差异有统计学意义（P〈O．05）,肝外胆管不显示、肝脾肿大在IHS组与BA组间差异无统计学意义（P〉0．05）。结论：胆道闭锁的N—CTCP表现具有一定特征性,肝门区三角形低密度影、小胆囊、门静脉间隙增宽出现“双边征”或“靶征”是诊断BA的重要征象。     

Biliary atresia in neonates and infants: triangular area of high signal intensity in the porta hepatis at T2-weighted MR cholangiography with US and histopathologic correlation

PURPOSE: To correlate a triangular area of high signal intensity in the porta hepatis on T2-weighted magnetic resonance (MR) cholangiograms of biliary atresia with ultrasonographic (US) and histopathologic findings in a portal mass observed during a Kasai procedure. MATERIALS AND METHODS: Twenty-one consecutive neonates and infants (age range, 13-88 days; mean age, 59 days) with cholestasis underwent US and single-shot MR cholangiography. In 12 patients with biliary atresia diagnosed at histopathologic examination, MR cholangiographic findings in the porta hepatis were correlated with US and histopathologic findings in the portal mass. RESULTS: At US, eight of the 12 patients had round, linear, or tubular hypoechoic portions within a triangular cord; MR cholangiography revealed a triangular area of high signal intensity confined to the porta hepatis. Histopathologic examination of the portal mass revealed a cystic or cleftlike lesion surrounded by loose myxoid mesenchyme and platelike fetal bile ducts. Neither the large cystic lesion without ductal epithelium nor the small cleftlike lesion with scanty epithelium demonstrated bile staining. Similar areas of high signal intensity were not seen on T2-weighted images in the remaining patients (four with biliary atresia and nine with neonatal hepatitis). CONCLUSION: In biliary atresia, T2-weighted single-shot MR cholangiography can show a triangular area of high signal intensity in the porta hepatis that may represent cystic dilatation of the fetal bile duct.     

Improved diagnosis of extraheptic biliary atresia by high frequency ultrasound of the gall bladder.

Ultrasound scanning using a 13 MHz probe was performed on 158 infants, aged 12 weeks or less, presenting with conjugated hyperbilirubinaemia. The gall bladder was identified in 156 infants, 35 of whom had biliary atresia. The two patients in whom no gall bladder was seen both had biliary atresia. The gall bladder shape was normal in 128 patients (9 with biliary atresia) and irregular in 28 patients (26 with biliary atresia). The gall bladder wall was regular in 121 patients (4 with biliary atresia) and irregular in 35 patients (31 with biliary atresia). Combining these findings gave a sensitivity of 91.9%, a specificity of 96.7%, a positive predictive value of 89.5%, a negative predictive value of 97.5% and an accuracy rate of 95.6% for ultrasound of the gall bladder in the identification of biliary atresia. This compares with 90%, 92.4%, 75.3%, 97.3% and 91.9%, respectively, in our previous report using a 7 MHz probe.     

Post-portoenterostomy triangular cord sign prognostic value in biliary atresia: a prospective study

The triangular cord sign (TC sign) is a sensitive and specific tool in prompt diagnosis of extrahepatic biliary atresia. The objective of this study is to evaluate post-operative TC sign presence in outcome prediction of infants with biliary atresia after Kasai hepato-portoenterostomy 27 infants and children with biliary atresia underwent 122 ultrasound examinations using both 5 MHz and 7 MHz convex linear transducers in 33 months follow up. For all infants TC sign identification was included pre-operatively, ultrasound was done 2 weeks post-operatively then bimonthly for 3 months, monthly for 2 months and every 3 months thereafter. 14 (53.8%) had post-operative TC sign. Once post-operatively positive, it remained positive throughout the study. It did not reappear in an initially post-operatively TC sign negative infant. Those having post-operative TC sign had statistically worse outcomes (0 became anicteric, 2 improved, 7 had progressive disease and 6 died) than those with a negative TC sign (p = 0.04) (3 became anicteric, 5 improved, 2 progressed and 1 died). Presence of TC sign post-operatively correlated with measure of removal of all fibrous cone at porta-hepatis during portoenterostomy (p = 0.026). Post-portoenterostomy TC sign is associated with more morbidity and mortality; and reflects inadequate surgical technique.     

^99mTc—EHIDA肝胆显像和腹部超声检出肝外胆道闭锁的评价

目的 :评价肝胆显像和腹部超声检出肝外胆道闭锁 (EHBA)的临床价值。材料和方法 :回顾性分析 119例持续黄疸婴儿肝胆显像和腹部超声检查结果。结果 :肝胆显像检出肝外胆道闭锁的灵敏度 ( 10 0 % )高于腹部超声 ( 79% ) ,以2 4小时内肠道无放射性出现 /未见功能胆囊显影作为EHBA的诊断依据时 ,肝胆显像的特异性可提高至 88% ,但与腹部超声特异性无差异 ,肝胆显像的准确度可提高到 92 % ,高于腹部超声。结论 :肝胆显像检出EHBA的灵敏度高于腹部超声 ,注意观察胆囊显影及其收缩情况可进一步改善其特异性和准确度 ,是临床检出胆道闭锁的首选方法。     

MR cholangiography in the evaluation of neonatal cholestasis: initial results

PURPOSE: To retrospectively analyze prospective magnetic resonance (MR) cholangiographic interpretations of findings and compare them with clinical outcome and to determine the accuracy of MR cholangiography in depicting extrahepatic biliary atresia and helping to distinguish it from other causes of neonatal jaundice. MATERIALS AND METHODS: Twenty-six infants (15 male, 11 female; median age, 2 months) underwent MR cholangiography with a 1.5-T MR imaging unit. Original interpretations were compared with clinical outcome. Statistical analysis was performed to determine the accuracy of MR cholangiography in depicting extrahepatic biliary atresia. Equivocal cases and any cases lost to follow-up were excluded. RESULTS: Findings in six of 26 infants were interpreted as normal, and none of five patients (one lost to follow-up) had biliary atresia or other surgical lesions; two were abnormal but not suggestive of biliary atresia (one false-negative finding); 12 were consistent with biliary atresia (three false-positive findings); four demonstrated a choledochal cyst; and two were equivocal. MR cholangiography accuracy was 82% (19 of 23); sensitivity, 90% (nine of 10); and specificity, 77% (10 of 13) for the detection of extrahepatic biliary atresia, with a positive predictive value of 75% (nine of 12) and a negative predictive value of 91% (10 of 11). CONCLUSION: Results of this study found that MR cholangiography is 82% accurate, 90% sensitive, and 77% specific for depicting extrahepatic biliary atresia. Contrary to previous reports, false-positive and false-negative findings occur at MR cholangiography.     

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

AimTo retrospectively analyze different methods in differentiating biliary atresia from idiopathic neonatal hepatitis.MethodsSixty-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.ResultsThere 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%.ConclusionOur 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.     

Radiological features of AIDS related cholangitis

Cryptosporidial infection is one of the recognised causes of diarrhoea in AIDS patients. It may also produce biliary tract disease. Fifteen out of 250 (6%) AIDS patients seen at our hospital had Cryptosporidial enteritis and five of the 15 (2% total) had clinical evidence of biliary tract disease. The radiological findings in these five patients are presented. Ultrasound examination of all five patients showed abnormalities in the biliary tree; five had dilatation and irregularity of the intra- and extrahepatic bile ducts with focal strictures, four had gall-bladder wall thickening, two had thickening of the common bile duct wall, two patients showed areas of increased reflectivity in the periductal regions of the liver and two had pancreatic duct dilatation. ERCP in one patient confirmed the ultrasound findings and Cryptosporidium oocytes were isolated from the collected bile. We conclude that Cryptosporidial infection in the biliary tree can produce distinctive appearances on ultrasound which may well obviate the need for more invasive investigations such as ERCP.     

Ultrasonographic Diagnosis of Biliary Atresia Based on a Decision-Making Tree Model

ObjectiveTo assess the diagnostic value of various ultrasound (US) findings and to make a decision-tree model for US diagnosis of biliary atresia (BA).ResultsMultivariate logistic regression analysis showed that abnormal gallbladder morphology and greater triangular cord thickness were significant predictors of BA (p = 0.003 and 0.001; adjusted odds ratio: 345.6 and 65.6, respectively). In the decision-making tree using conditional inference tree analysis, gallbladder morphology and triangular cord thickness (optimal cutoff value of triangular cord thickness, 3.4 mm) were also selected as significant discriminators for differential diagnosis of BA, and gallbladder morphology was the first discriminator. The diagnostic performance of the decision-making tree was excellent, with sensitivity of 100% (46/46), specificity of 94.4% (51/54), and overall accuracy of 97% (97/100).ConclusionAbnormal gallbladder morphology and greater triangular cord thickness (> 3.4 mm) were the most useful predictors of BA on US. We suggest that the gallbladder morphology should be evaluated first and that triangular cord thickness should be evaluated subsequently in cases with normal gallbladder morphology.     

薄层冠扫SSFSE序列在婴幼儿MR胆道成像中的应用

目的：分析探讨薄层冠扫SSFSE序列在婴幼儿MR胆道成像中的临床应用价值。方法：婴幼儿胆道系统疾病患者24例,包括胆道闭锁7例、胆道扩张症13例、胆系结石4例,均行全腹部薄层冠状面单次激发快速自旋回波（SS-FSE）序列扫描,8例经15～20min延迟后行MRI增强扫描。观察患儿肝内外胆道及其各级分支的解剖全貌、走行分布及通畅情况。结果：所有患儿的MR图像在显示肝胆管解剖方面均可达到质量良好（可显示肝内胆管二级以上分支）。胆道闭锁患儿表现为胆囊形态小或不显影,正常肝外胆道结构消失或显示不完整;胆道扩张症患儿表现为位于胆道走行区的囊性包块,伴或不伴有肝内外胆道不同程度扩张;胆系结石患儿表现为胆道／胆囊内短T2信号充盈缺损,或伴近端胆道扩张。结论：薄层冠扫SSFSE序列具有扫描速度快、呼吸伪影少、无电离辐射、胆道系统与周围背景结构的对比度高等优势,较常规腹部MRI扫描能更细致地观察胆道系统的解剖结构和各级分支的走行、管径,了解病变全貌以及是否合并其它脏器异常,可作为婴幼儿胆道疾病的常规影像学检查手段。     

The significance of functioning gallbladder visualization on hepatobiliary scintigraphy in infants with persistent jaundice.

The purpose of this study was to determine whether gallbladder visualization can help exclude biliary atresia in hepatobiliary scintigraphic studies of infants with persistent jaundice. METHODS: One hundred fifty-two infants with persistent jaundice (49 patients with a final diagnosis of biliary atresia and 103 with biliary patency) were studied using both hepatobiliary scintigraphy and abdominal sonography. Food was withheld for 4 h before the examination, and the infants were fed nothing but glucose until 6 h after the initial injection of (99m)Tc-disofenin or until the gallbladder was seen. If the gallbladder was seen, the infants were fed milk, and imaging was continued to observe gallbladder contractility. RESULTS: In none of the 49 patients with biliary atresia could the gallbladder be seen with hepatobiliary scintigraphy, but abdominal sonography revealed 9 normal-sized gallbladders. Of the 103 patients with biliary patency, hepatobiliary scintigraphy detected the gallbladder more frequently (74%, 76/103) than did abdominal sonography (63%, 65/103). All visualized gallbladders contracted after the infants were fed milk. If we include visualization of both the gallbladder and bowel radioactivity as criteria, the specificity of biliary atresia on hepatobiliary scintigraphy increases to 86% (89/103). CONCLUSION: Gallbladders were usually visible on hepatobiliary scintigraphy of fasting patients with biliary patency. A functioning gallbladder, with or without visualization of bowel radioactivity, indicated biliary patency.     

The investigation of neonatal obstructive jaundice using 123I rose bengal

With the development of new surgical techniques the outlook for infants with biliary atresia has improved significantly. It has therefore become increasingly important to identify these patients quickly in order to allow prompt surgical intervention. Differentiation of biliary atresia from other causes of jaundice, in particular idiopathic neonatal hepatitis, is often difficult as there is considerable clinical and histological overlap of the two conditions. Demonstration of biliary patency using radiopharmaceuticals is a well established technique. 131I rose bengal and the 99Tcm-labelled iminodiacetic acid derivatives have both been used, but are not completely satisfactory, and controversy still exists as to which is the most suitable agent. Nine infants with prolonged jaundice have been studied using 123I-labelled rose bengal. All infants with biliary atresia and neonatal hepatitis were correctly identified. The results indicate that 123I rose bengal provides a reliable tracer for assessing biliary patency and is the agent of choice in the investigation of neonatal obstructive jaundice.     

Ursodeoxycholic acid-augmented hepatobiliary scintigraphy in the evaluation of neonatal jaundice.

Early differentiation of extrahepatic biliary atresia from intrahepatic cholestasis is important. Hepatobiliary scintigraphy is an excellent noninvasive investigation for ruling out extrahepatic biliary atresia. This study aimed at identifying the role of ursodeoxycholic acid (UDCA), a choleretic agent, in conjunction with hepatobiliary scintigraphy in differentiating extrahepatic biliary atresia from neonatal hepatitis. METHODS: Fifty-one infants (42 male, 9 female) aged 0.3-5.5 mo (mean, 2.9 mo) presenting with neonatal jaundice underwent 99mTc-mebrofenin hepatobiliary scintigraphy. For patients who did not show any excretion of tracer into the intestine till 24 h, the study was repeated after oral administration of UDCA (20 mg/kg every 12 h) for 48-72 h. Ultrasonography and, if required, liver biopsy and intraoperative cholangiography were used with clinical data such as stool color and serologic and other etiologic investigations to form a final diagnosis. RESULTS: Of 51 patients, 19 showed biliary excretion in the first study, ruling out extrahepatic biliary atresia. Neonatal hepatitis was the final diagnosis in these. Of the remaining 32 patients, 12 nonexcretors converted to excretors after UDCA treatment, whereas 20 still showed no biliary drainage. Four nonexcretors on scintigraphy had a final diagnosis of neonatal hepatitis with galactosemia; the remaining 16 had extrahepatic biliary atresia. The specificity of hepatobiliary scintigraphy in ruling out extrahepatic biliary atresia improved from 54.3% to 88.6% (P < 0.001) after UDCA treatment. None of the patients experienced any ill effects from UDCA administration. CONCLUSION: Pretreatment with UDCA significantly improves the specificity of hepatobiliary scintigraphy in ruling out extrahepatic biliary atresia as a cause of prolonged neonatal jaundice.     

US approach to jaundice in infants and children.

High-resolution real-time ultrasonography (US) serves as an important tool for differentiation of obstructive and nonobstructive causes of jaundice in infants and children, independent of liver function. Unconjugated hyperbilirubinemia occurs in approximately 60% of normal term infants and in 80% of preterm infants. Persistence of neonatal jaundice beyond 2 weeks of age demands US evaluation to differentiate between the three most common causes: hepatitis, biliary atresia, and choledochal cyst. In all three conditions, the hepatic echotexture is diffusely coarse and hyperechoic, but this appearance may be seen in a variety of hepatic inflammatory, obstructive, and metabolic processes. Thus, hepatic scintigraphy and at times percutaneous liver biopsy are necessary to narrow the differential diagnosis and to identify patients who require more invasive techniques (eg, intraoperative cholangiography). US is useful for demonstrating inspissated bile and biliary duct stones. In infants, stones are usually secondary to obstructive congenital anomalies of the biliary tract, total parenteral nutrition, furosemide treatment, phototherapy, dehydration, infection, hemolytic anemia, and short-gut syndrome, whereas in older children, stones are usually associated with sickle cell disease, bowel resection, hemolytic anemia, and choledochal cyst. Jaundice in infants and children may also be due to cirrhosis, benign strictures, and neoplastic processes.     

胆道闭锁的超声诊断

目的:总结小婴儿胆道闭锁的超声图像特点,探讨胆囊形态与胆道闭锁的关系.方法:回顾性分析40例经手术病理证实的胆道闭锁婴儿肝胆超声表现,并结合同期经手术证实的非闭锁性黄疸病例加以讨论.结果:胆囊未显示2例.胆囊显示38例,17例长径小于1.5cm,内径2～3mm,其中3例胆囊长径小于0.5cm,内径1mm.17例胆囊长径...