Doppler ultrasound in the diagnosis of Budd-Chiari syndrome in children after split liver transplantation.

PURPOSE: To assess the capabilities of a velocity ratio>3 for the diagnosis of Budd-Chiari syndrome (BCS) in children after split liver transplantation using Doppler ultrasonography (DUS). MATERIALS AND METHODS: A total of 28 children who underwent liver transplantation using a split procedure were included. There were 11boys and 17girls with a mean age of 3.8years (range: 0.7-12years). Velocity ratio between blood velocity upstream of the anastomosis and that at the level of the inferior vena cava anastomosis was calculated. Sensitivity, specificity and accuracy of DUS for the diagnosis of BCS were estimated using a velocity ratio>3. RESULTS: Eight children (8/28; 29%) had BCS and 20 (20/28; 71%) did not have BCS using the standard of reference. A velocity ratio>3 on DUS yielded 88% sensitivity (95% CI: 53-98%), 80% specificity (95% CI: 58-92%) and 82% accuracy (95% CI: 64-92%) for the diagnosis of BCS. CONCLUSION: A velocity ratio>3 on DUS is a reliable finding for the diagnosis of BCS in children after split liver transplantation.

Herman score in prenatal screening for Down syndrome: Can a junior assess a senior?

PURPOSE: To compare Herman scores self-assessed prospectively during ultrasound first-trimester screening by a single senior radiologist with 15 years of experience, to those obtained retrospectively by an unexperienced junior radiologist. MATERIALS AND METHODS: Over a 18-month period, a single senior radiologist measured the nuchal translucency thickness along with calculation of Herman scores. An independent junior radiologist subsequently reviewed and scored the images. RESULTS: A total of 301 patients were included. The mean Herman score was 8.2±0.9 (SD) for the senior radiologist and 7.8±0.9 (SD) after review by the independent junior radiologist (P<0.001). The scores for caliper position and fetal head position decreased significantly after the independent review. The two criteria on which the two operators disagreed the least were visualization of the nuchal translucency and the distinction between neck and amnios. CONCLUSION: Herman score is lower after review by a junior radiologist, without any effect on patient's management and follow-up.

[Segmental approach to congenital heart diseases: Principles and applications to prenatal imaging]. / Approche segmentaire des cardiopathies congénitales : principes et applications en imagerie prénatale.

This pictorial essay will initially present the origin, definitions, objectives and main principles of the segmental approach to congenital heart diseases. Then, through ultrasound scans iconography we will consider its practical applications to prenatal screening. Eventually, through both ultrasound and MRI cases, we will discuss its potential use in fetal diagnostic evaluation.

Multimodality imaging of aortic coarctation: From the fetus to the adolescent.

Aortic coarctation is a local narrowing of the aortic lumen, which is located at the level of the isthmus in 95% of patients. Aortic coarctation accounts for 5 to 8% of all congenital heart diseases. It may have an acute presentation in the form of heart failure in the neonate or may be discovered incidentally in adult because of severe treatment-resistant hypertension. Ultrasound may reveal the presence of aortic coarctation during the antenatal period. In this situation, associated abnormalities should be investigated (including karyotype), because they influence prognosis and indicates whether or not the birth should occur in a center with pediatric cardiology expertise. Postnatally, ultrasound and chest radiography are the basic imaging work-up. Computed tomography is often the second line imaging investigation in infants and young children for whom magnetic resonance imaging fails to confirm the diagnosis. Magnetic resonance imaging with cardiac synchronization is the preferred imaging tool in the post-treatment period. Aortic coarctation may be treated surgically or by endovascular techniques. Potential complications should be searched for using ultrasound and magnetic resonance imaging.

Detection of pulmonary and coronary artery anomalies in tetralogy of Fallot using non-ECG-gated CT angiography.

OBJECTIVES: To evaluate the use of non-ECG-gated computed tomography (CT) angiography to describe pulmonary and coronary defects in patients with tetralogy of Fallot (TOF). PATIENTS AND METHODS: This retrospective study was carried out on TOF patients having undergone pre-operative non-ECG-gated CT angiography between February 2007 and September 2012. The following clinical parameters were recorded: mean age at CT angiography, sex, the existence of genetic disease and the need to sedate the patient prior to CT angiography. CT data were analyzed retrospectively to determine the site(s) of pulmonary stenosis (infundibular, valvular or arterial), the size of pulmonary arteries and the presence of anomalous coronary artery courses. CT findings were then compared to the anatomy observed during surgery. RESULTS: Thirty-five patients were included in the study. The mean age was 4.30±1.91months (boys/girls=17/18). Two patients had associated chromosome disorders (one 22q11 microdeletion and one CHARGE syndrome). Sixteen patients (45.71%) were sedated prior to CT. Pulmonary artery assessment revealed 24 patients (68.57%) with infundibular stenosis, 5 (17.5%) with infundibular and/or valvular stenosis, and 6 (21%) with anomalous pulmonary arteries. CT angiography also evidenced anomalous coronary arteries in 8 patients (22.85%). CONCLUSION: Due to its reduced scanning time and high spatial resolution, non-ECG-gated CT angiography is a non-invasive imaging modality that provides accurate information on pulmonary and coronary artery anatomy in patients with TOF.

Prenatal diagnosis of bowel malposition using T2-weighted fetal MRI sequences.

OBJECTIVE: The goal of this study was to investigate the capability of T2-weighted magnetic resonance imaging (MRI) in revealing fetal bowel malposition. MATERIALS AND METHODS: All fetal MRI examinations (excluding central nervous system MRI examinations) performed in our department from January 2005 to January 2014 were retrospectively studied by 2 independent observers for situs, stomach and jejunum location on T2-weighted images. Patients data were also reviewed for results of ultrasound examinations, MRI indication, and gestational age. Abnormally positioned jejunums were classified into 3 groups: intrathoracic (A), extra-fetal (B) and abnormal intra-fetal (C). Prenatal data were compared to postnatal imaging, surgery or autopsy findings that served as standard of reference. RESULTS: A total of 709 fetal MRI examinations were analyzed. In 64 fetus (9%), the jejunum was not present in the left subgastric area on T2-weighted MR images. In these 64 fetuses, proximal jejunum was intrathoracic (41/64, 64%, group A), extra-fetal (11/64, 17%, group B), or intra-abdominal but abnormally positioned (12/64, 19%, group C). Interobserver agreement was 100%. All diagnoses for fetuses in groups A and B (52 cases) were confirmed postnatally (41 cases) or at autopsy (11 cases). In group C, bowel malposition was suspected after ultrasound in only 2/12 fetuses (16.6%); it was confirmed postnatally in 1 fetus but not confirmed in the remaining one. In the 10 remaining fetuses (83%), malposition was confirmed postnatally although not initially suspected. CONCLUSION: T2-weighted fetal MR images are useful for the prenatal diagnosis of bowel malposition, even when they are unsuspected on ultrasound examination.

Cardiac CT or MRI in pediatric practice: Which one to choose?

The different factors involved in the choice of the best cardiovascular imaging examination for pediatric patients are justification, radiation protection, sedation, resolutions (spatial and contrast), morphology or function, intervention and contrast enhancement. Computed tomography is preferable for all coronary artery conditions, any arterial or venous abnormalities in newborns and infants and in the preoperative assessment for tetralogy of Fallot. Magnetic resonance imaging is used for any tumoral or functional assessment, cardiomyopathy or arrhythmia or if the child's participation and/or size of the structures being examined allows using this technique.

Contribution of the foetal uro-MRI in the prenatal diagnosis of uronephropathies.

PURPOSE: To study the complementary diagnostic value and role in the perinatal management of foetal MRI in the prenatal diagnosis of abnormalities of the urinary tract. PATIENTS AND METHODS: Retrospective monocentric study from November 2002 to June 2011 of foetuses benefiting from an MRI after ultrasound diagnosis of uronephropathy abnormalities. Ultrasound and MRI data were compared with postnatal radiological and/or surgical data or with the foetopathology. The MRI analysis focused on the diagnostic concordance with the ultrasound, the complementary diagnostic contribution and/or a change in perinatal care. RESULTS: Of the 154 MRI examined, a follow-up was obtained for 108 cases. The indications for MRI were classified into six groups: suspected renal agenesis (n = 20, 18.5%), posterior urethral valve (n = 20, 18.5%), reflux or megaureter (n = 14, 13%), uretropelvic junction syndrome (n = 24, 22.5%), enlarged kidneys (n = 7, 6.5%) and others (n = 23, 21%). The information supplied by ultrasound was confirmed by MRI in 72 patients (67%). MRI provided additional data for 36 patients (33%) and changed the perinatal care for 16 patients (15%). CONCLUSION: Foetal uro-MRI is a useful complementary tool in the prenatal diagnosis of some uropathy abnormalities.