The use of magnetic resonance cholangiopancreatography in children

[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.

Comparison of quantitative 3D magnetic resonance cholangiography measurements obtained using three different image acquisition methods

PURPOSE

To compare quantitative biliary measurements obtained with three different magnetic resonance cholangiopancreatography (MRCP) acquisition methods.

METHODS

This retrospective study was IRB-approved. Patients with combinations of clinically indicated 3D FSE MRCP with sensitivity encoding (SENSE), 3D FSE SENSE MRCP with compressed sensing (CS-FSE; acceleration factor 8), and 3D gradient and spin-echo (GRASE) MRCP, acquired between October 2018 and March 2020, were included. The MRCP + Tuning Threshold algorithm (Perspectum Ltd., Oxford, UK) was used to segment 3D biliary models from MRCP data, with multiple metrics quantified from the models. Single measure, two-way, mixed-effects intra-class correlations, Bland-Altman analyses, and Wilcoxon signed-rank tests were used to compare quantitative measurements.

RESULTS

From 160 MRCP datasets (25 3D FSE, 67 3D CS-FSE, 68 3D GRASE) in 69 patients, 48 datasets (7 [28%] 3D FSE, 14 [21%] 3D CS-FSE, 27 [40%] 3D GRASE) failed post-processing due to motion artifacts. The remaining 112 MRCP datasets (18 3D FSE, 53 3D CS-FSE, 41 3D GRASE) from 60 patients were included in the analysis. There was good to excellent agreement between 3D FSE and 3D CS-FSE MRCP for diameter of the left and right hepatic ducts, biliary volume, number and length of ducts, and total length of dilations (ICC: 0.83-0.93). The only metrics that exhibited good agreement between 3D FSE and 3D GRASE MRCP were biliary volume (ICC: 0.75) and total number of dilations (ICC: 0.77).

CONCLUSION

3D CS-FSE MRCP produces comparable biliary diameter metrics and global duct quantification to 3D FSE MRCP at a significantly reduced acquisition time.

Assessment of exocrine pancreatic function in children and adolescents with direct and indirect testing

The exocrine pancreas plays an important role in digestion. Understanding of the physiology and regulation of exocrine function provides insight into disease processes and basis of functional testing. Specifically, exocrine pancreatic insufficiency (EPI) can cause maldigestion and thus a proper assessment of exocrine pancreatic function is important. There are indirect and direct methods for evaluating pancreatic function. Indirect methods are varied and include stool, serum, urine, and breath tests. Fecal elastase is a commonly used indirect test today. Direct methods involve stimulated release of pancreatic fluid that is collected from the duodenum and analyzed for enzyme activity. The most used direct test today is the endoscopic pancreatic function test. Indirect pancreatic function testing is limited in identifying cases of mild to moderate EPI, and as such in these cases, direct testing has higher sensitivity and specificity in diagnosing EPI. This review provides a comprehensive guide to indirect and direct pancreatic function tests as well as an in-depth look at exocrine pancreatic function including anatomy, physiology, and regulatory mechanisms.

Pediatric choledochal cysts: diagnosis and current management

Choledochal cysts are rare congenital disorders first described by Vater and Ezler in 1723. Their exact etiology remains incompletely understood; however, an anomalous pancreaticobiliary union (APBDU) and subsequent reflux of biliary contents into the biliary tree are thought to play a role. Accordingly, APBDU-associated choledochal cyst patients are significantly more likely to have evidence of hepatitis, cholangitis or pancreatitis and pathologically confirmed inflammation. In 1977, Todani and colleagues modified the original Alonso-Lej classification to include five types of CC. Type I and IV are the most common and most likely to be associated with malignancy. The majority of choledochal cysts are diagnosed in childhood. Clinical presentation varies and most often consists of nonspecific abdominal pain. Diagnosis is typically accomplished using multimodality imaging techniques including computed tomography, magnetic resonance imaging, ultrasound and MRCP. The use of diagnostic PTC and ERCP in CC has been largely replaced by MRCP. Appropriate management consists of prompt, complete cyst excision followed by restoration of biliary enteric continuity when necessary. Minimally invasive CC resection in the pediatric population has demonstrated acceptable outcomes. Prognosis is generally excellent; however, malignancy risk remains higher than the general population even after complete surgical excision.

Factors Interfering with Delineation on MRCP of Pancreaticobiliary Maljunction in Paediatric Patients

Background

The aim of this study was to assess factors for delineating the pancreaticobiliary junction in the presence of pediatric congenital choledochal cysts (CCC) using Magnetic resonance cholangiopancreatography (MRCP).

Methods

Retrospective review of medical records for 48 patients with CCC was conducted, including demographics, biliary amylase and MRCP findings if available. With univariate and multivariate logistic regression, we measured significant factors affecting pancreaticobiliary maljunction(PBM) diagnoses by MRCP.

Results

Of the subjects enrolled with CCC. Twenty-eight cases had PBM according to MRCP. Univariate analysis confirmed that age, cyst diameter > 30 mm and cysts that descended to the introitus pelvis affected junctional delineation and detection of PBM (P<0.05). Stepwise logistic regression analysis confirmed large cysts in the introitus pelvis predicted pancreaticobiliary junctional delineation in MRCP and these data agreed with the literature. A correlation between cyst diameter and the length of the common channel was found as was cyst diameter and biliary amylase although there were no significant differences between them.

Conclusions

Age, cyst diameter >30 mm and descending cysts into the introitus pelvis affected junctional delineation of the pancreatic and bile duct in PBM with MRCP. Large cyst descension into the introitus pelvis was an independent factors affecting PBM detection.

ESPGHAN and NASPGHAN Report on the Assessment of Exocrine Pancreatic Function and Pancreatitis in Children

The purpose of this clinical report is to discuss several recent advances in assessing exocrine pancreatic insufficiency (EPI) and pancreatitis in children, to review the array of pancreatic function tests, to provide an update on the inherited causes of EPI, with special emphasis on newly available genetic testing, and to review newer methods for evaluating pancreatitis.

Cholangiographic characteristics of common bile duct dilatation in children

AIM: To investigate whether children with congenital common bile duct dilatation (CBDD) differ from children with obstructive CBDD in cholangiographic characteristics.

METHODS: In this retrospective cohort study, the baseline data and the results of imaging analyses were reviewed among children who had endoscopic retrograde cholangiopancreatography (ERCP) due to CBDD. ERCP was performed on all pediatric patients by experienced pediatric endoscopists. The maximal transverse diameter of the common bile duct (CBD) was measured on ERCP. To assess whether age-adjusted CBDD could be used for differential diagnosis, a CBDD severity index (SI) was calculated by dividing the measured CBD diameter by the age-corrected maximal diameter of a normal CBD.

RESULTS: A retrospective medical chart review revealed that 85 consecutive children under 16 years of age with hepatobiliary disease and CBDD were referred to Seoul Asan Medical Center. Fifty-five (64.7%) children had congenital CBDD and 30 (35.3%) had obstructive CBDD. The two groups did not differ significantly in terms of clinical characteristics except for sex. The congenital and obstructive CBDD groups did not differ significantly in terms of mean CBD diameter (19.3 ± 9.6 mm vs 12.2 ± 4.1 mm, P > 0.05). However, congenital CBDD cases had a significantly higher mean SI than obstructive CBDD cases (3.62 ± 1.64 vs 1.98 ± 0.71, P = 0.01). In multivariate analysis, an SI value ≥ 2.32 and comorbidity with anomalous union of pancreaticobiliary duct (APBDU) in ERCP independently predicted congenital CBDD.

CONCLUSION: Measuring the CBD may aid the differential diagnosis of both CBDD and APBDU in children.

Changing pattern of indications of endoscopic retrograde cholangiopancreatography in children and adolescents: a twelve-year experience

BACKGROUND

There are few data regarding endoscopic retrograde cholangiopancreatography (ERCP) usefulness in children and adolescents. We reviewed the long-term experience with diagnostic and therapeutic ERCP in a tertiary single center in Southern Brazil.

METHODS

A retrospective chart review of patients aged 0-18 years who had undergone ERCPs from January 2000 to June 2012 was done. Data on demographics, indications, diagnosis, treatments, and complications were collected.

RESULTS

Seventy-five ERCPs were performed in 60 patients. The median age of the patients at the procedure was 13.9 years (range: 1.2-17.9). Of the 60 patients, 47 (78.3%) were girls. Of all ERCPs, 48 (64.0%) were performed in patients above 10 years and 35 (72.9%) of them were in girls. ERCP was indicated for patients with bile duct obstruction (49.3%), sclerosing cholangitis (18.7%), post-surgery complication (12%), biliary stent (10.7%), choledochal cyst (5.3%), and pancreatitis (4%). The complication rate of ERCP was 9.7% involving mild bleeding, pancreatitis and cholangitis. Patients who had therapeutic procedures were older (13.7±3.9 vs. 9.9±4.9 years; P=0.001) and had more extrahepatic biliary abnormalities (82% vs. 50%; P=0.015) than those who had diagnostic ERCPs. A marked change in the indications of ERCPs was found, i.e., from 2001 to 2004, indications were more diagnostic and from 2005 therapeutic procedures were predominant.

CONCLUSIONS

Diagnostic ERCPs are being replaced by magnetic resonance cholangiopancreatography and also by endoscopic ultrasound. All these procedures are complementary and ERCP still has a role for therapeutic purposes.

Diagnosis and management of choledochal cyst: 20 years of single center experience

We report the first case series from Africa and the Middle East on choledochal cyst, a disease which shows significant geographical distribution with high incidence in the Asian population. In this study, the epidemiological data of the patients are presented and analyzed. Attention was paid to diagnostic imaging and its accuracy in the diagnosis and classification of choledochal cyst. Most cases of choledochal cyst disease have type I and IV-A cysts according to the Todani classification system, which support the etiological theories of choledochal cyst, especially Babbitt's theory of the anomalous pancreaticobiliary duct junction, which are clearly stated. The difficulties and hazards of surgical management and methods used to avoid operative complications are clarified. Early and late postoperative complications are also included. This study should be followed by multicenter studies throughout Egypt to help assess the incidence of choledochal cysts in one of the largest populations in Africa and the Middle East.

Comparison of respiratory-triggered 3-D fast spin-echo and single-shot fast spin-echo radial slab MR cholangiopancreatography images in children

BACKGROUND

The two most commonly performed magnetic resonance cholangiopancreatography (MRCP) sequences, 3-D fast spin-echo (3-D FSE) and single-shot fast spin-echo radial slabs (radial slabs), have not been compared in children.

OBJECTIVE

The purpose of this study was to compare 3-D FSE and radial slabs MRCP sequences on a 3-T scanner to determine their ability to show various segments of pancreaticobiliary tree and presence of artifacts in children.

MATERIALS AND METHODS

We reviewed 79 consecutive MRCPs performed in 74 children on a 3-T scanner. We noted visibility of major ducts on 3-D FSE and radial slabs. We noted the order of branching of ducts in the right and left hepatic ducts and the degree of visibility of the pancreatic duct. Statistical analysis was performed using McNemar and signed rank tests.

RESULTS

There was no significant difference in the visibility of major bile ducts and the order of branching in the right hepatic lobe between sequences. A higher order of branching in the left lobe was seen on radial slabs than 3-D FSE (mean order of branching 2.82 versus 2.27; P-value = 0.0002). The visibility of pancreatic duct was better on radial slabs as compared to 3-D FSE (mean value of 1.53 vs. 0.90; P-value < 0.0001). 3-D FSE sequence was artifact-free in 25/79 (31.6%) MRCP exams as compared to radial slabs, which were artifact-free in 18/79 (22.8%) MRCP exams (P-value = 0.0001).

CONCLUSION

There is no significant difference in the visibility of major bile ducts between 3-D FSE and radial slab MRCP sequences at 3-T in children. However, radial slab MRCP shows a higher order of branching in the left hepatic lobe and superior visibility of the pancreatic duct than 3-D FSE.

MR cholangiopancreatography at 3.0 T in children: diagnostic quality and ability in assessment of common paediatric pancreatobiliary pathology

OBJECTIVE

To assess the diagnostic quality of MR cholangiopancreatography (MRCP) at 3.0 T in children and to assess its diagnostic ability in answering the clinical query. Also, to determine the frequency of artefacts and anatomic variations in ductal anatomy.

METHODS

Consecutive MRCPs performed in children using a 3-T scanner were retrospectively reviewed to note indications, findings, imaging diagnosis, normal variants, quality and artefacts. Analysis was performed based on the final diagnosis assigned by pathology or the combination of clinical, laboratory, imaging features and follow-up to determine whether it was possible to answer the clinical query by MRCP findings.

RESULTS

There were 82 MRCPs performed at 3.0 T on 77 children. 42/82 (51%) MRCPs were of good quality, 35/82 (43%) MRCPs were suboptimal but diagnostic and the remaining 5/82 (6%) MRCPs were non-diagnostic. MRCP answered the clinical query in 61/82 (74%) cases; however, it did not answer the clinical query in 11/82 (14%) cases and was equivocal in 10/82 (12%) cases. There was significant association between the quality of MRCP and the ability of MRCP to answer the clinical query (p<0.0001). 64/82 (78%) MRCP examinations had at least 1 artefact. Variation in the bile duct anatomy was seen in 27/77 (35%) children.

CONCLUSION

MRCP performed at 3.0 T is of diagnostic quality in most cases and is able to provide an answer to the clinical query in the majority of cases.

ADVANCES IN KNOWLEDGE

3-T MRCP is feasible and useful in the assessment of pancreatobiliary abnormalities in children.

Laparoscopic cholecystectomy in children with sickle cell anemia and the role of ERCP

BACKGROUND

Patients with sickle cell anemia (SCA) have a high incidence of cholelithiasis and choledocholithiasis. This report is an analysis of our experience with laparoscopic cholecystectomy (LC) for children with SCA and the role of endoscopic retrograde cholangiopancreatography (ERCP).

PATIENTS AND METHODS

The records of children with SCA who had cholecystectomy were retrospectively reviewed for age, sex, hemoglobin level, hemoglobin electrophoresis, indication for cholecystectomy, operative time, hospital stay, and postoperative complications. They were divided into 2 groups, open cholecystectomy (OC) group and LC group, and the 2 were compared in terms of operative time, hospital stay, and postoperative complications.

RESULTS

Over a period of 15 years (January 1995 and December 2009), 94 children with SCA had cholecystectomy. Thirty-five (19 males and 16 females) had OC, 52 (28 males and 24 females) had LC, and 7 (4 males and 3 females) had LC and splenectomy. Their age ranged from 4 to 15 years (mean, 11.4 y). The indications for cholecystectomy were biliary dyspepsia and biliary colic (55), acute cholecystitis (7), obstructive jaundice (17), asymptomatic (12), and biliary pancreatitis (3). All those who had OC underwent intraoperative cholangiogram, 9 of them (25.7%) had common bile duct (CBD) exploration and 2 transduodenal sphincterotomy. Of those who had LC, 13 (25%) underwent preoperative ERCP, which was normal in 1, showed dilated CBD with no stones in 2, and dilated CBD with stones in 7. In 3, ERCP showed dilated CBD with enlarged, inflammed papilla suggestive of recent stone passage. Nine underwent endoscopic sphincterotomy and stone extraction followed by LC. There was no mortality; 1 (2.1%) required conversion to OC and another underwent postoperative exploration because of bleeding from an accessory cystic artery. In the LC group, 4 (7.7%) developed minor postoperative complications, whereas 8 (22.9%) in the OC group developed complications.

CONCLUSIONS

With proper perioperative management, LC is feasible, safe, and superior to OC in children with SCA with regard to postoperative complications, duration of hospital stay, cosmetic appearance, and postoperative recovery. LC should be the treatment of choice for both symptomatic and asymptomatic cholelithiasis in children with SCA. ERCP is a valuable diagnostic and therapeutic investigation both preoperatively and postoperatively. The sequential approach of endoscopic sphincterotomy and stone extraction followed by LC is a safe and effective approach for the management of cholelithiasis and choledocholithiasis in children with SCA.

Concordance of imaging modalities and cost minimization in the diagnosis of pediatric choledochal cysts

PURPOSE

Given evolving imaging technologies, we noted significant variation in the diagnostic evaluation of pediatric choledochal cysts (CDC). To streamline the diagnostic approach to CDC, and minimize associated expenses, we compared typing accuracy and costs of ultrasound (US), intraoperative cholangiography (IOC), and magnetic resonance cholangiopancreatography (MRCP).

METHODS

Records of 30 consecutive pediatric CDC patients were reviewed. Blinded to all clinical data, two pediatric radiologists reviewed all US, MRCPs, and IOCs to type CDCs according to the Todani classification. When compared with pathologic findings, the concordance between and accuracy of each diagnostic test were determined. Inflation-adjusted procedure charges and collections for imaging modalities were analyzed.

RESULTS

Mean typing accuracy overlapped for US, IOC, and MRCP. Inter-rater reliability was 87 % for US (κ = 0.77), 80 % for IOC (κ = 0.62), and 60 % for MRCP (κ = 0.37). MRCP procedure charges ($1204.69) and collections ($420.85) exceeded IOC and US combined ($264.80 charges, p = 0.0002; $93.40 collections, p = 0.0021).

CONCLUSION

Our data support the use of US alone in the diagnosis of pediatric CDC when no intrahepatic biliary ductal dilatation is visualized. However, when dilated intrahepatic ducts are encountered on US, MRCP should be utilized to distinguish a type I from a type IV CDC, which may alter the operative approach.

Choledochal cysts in infants and children: experiences over a 20-year period at a single institution

This analysis was undertaken to compare the clinicopathological features of infants with choledochal cysts to those of older children with these entities and to evaluate the surgical outcomes for both subject groups. The medical records of all children admitted to the Cathay General Hospital with choledochal cysts over a 20-year period were retrospectively reviewed. Twenty-five subjects were included and divided into the infant (<1 year at presentation; 8 subjects) and classical pediatric (1-18 years at presentation; 17 subjects) groups. Anatomical subtypes were: IA (16), IC (6), and IVA (3). The median biliary amylase value was markedly elevated for the pediatric group but not for the infant group. Most (82.4%) patients in the pediatric group, but none in the infant group, presented with abdominal pain. Jaundice and clay-colored stool were present in all patients in the infant group but only 35% of those in the pediatric group. All patients underwent choledochocystectomy and Roux-en-Y hepaticojejunostomy with good outcomes. Neonates/infants with choledochal cysts present differently from older children with these entities. Amylase measurements may serve to distinguish biliary atresia with cystic dilatation from choledochal cyst in neonates/infants. Prognosis following radical cyst excision and reconstruction with Roux-en-Y hepaticojejunostomy is excellent.

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.

Pancreatitis in children and adolescents

Several clinical and methodologic difficulties occur when diagnosing acute pancreatitis in the pediatric age group. Due to its uncommonness and heterogeneous symptoms, acute pancreatitis in children is often misdiagnosed, and prospective studies are lacking. Guidelines for classifying, diagnosing, and managing acute pancreatitis are frequently based on standards that are developed and validated in adult patients. Among the broad range of etiologies of pediatric acute pancreatitis in children, gallstones and biliary disease may play a greater role than previously believed. Although it is typically a benign disease in the pediatric population, complications such as pseudocysts may occur. When there are fatalities, they are usually attributed to systemic illness rather than the pancreatitis itself. Improvements in diagnostic and imaging methods and growing awareness cannot account for the recent increases in the observed incidence of pediatric acute pancreatitis.