US assessment of neonatal bowel (necrotizing enterocolitis excluded).

US plays a main role in evaluating neonatal gastrointestinal disorders. The authors describe the US appearance of normal neonatal bowel, midgut volvulus, small bowel atresia, meconium ileus, meconium peritonitis, different meconium plug syndromes, Hirschsprung disease, intestinal duplication cysts, some other abdominal cysts, some intraperitoneal infections, excluding necrotizing enterocolitis, and anorectal anomalies. The use of sonography in the imaging diagnostic strategies of these congenital and acquired anomalies is emphasized.

Abdominal imaging in child abuse.

INTRODUCTION: Abdominal injuries in abused children are less common than musculoskeletal and craniocerebral injuries; however they carry high mortality and morbidity rates. In every case of trauma, regardless of aetiology, radiologists are responsible for the documentation and evaluation of injuries. INJURIES: Any abdominal injury pattern maybe observed following physical abuse and none is specific for abuse. However, a high index of suspicion should be maintained for every case of pancreatic, hollow viscous and other solid organ injuries, especially when there is delay in seeking help, a history of trauma to the child or siblings, young age, undernourishment, ecchymosis in non-ambulatory children or a non-plausible explanation for the injuries based on the provided history and the psychomotor condition of the child. IMAGING MODALITIES: CT with intravenous contrast material is the imaging modality of choice in every suspected inflicted abdominal injury. US could be the first imaging test for abused children with a low probability of abdominal injury and for follow-up. Upper gastrointestinal series could reveal acute or resolving mural haematomas in children with equivocal CT or US findings. CONCLUSION: Child abuse should be considered in the differential diagnosis of acute abdominal symptoms in young children.

Severe hypothyroidism after contrast enema in premature infants.

Premature newborns are particularly vulnerable to iatrogenic hypothyroidism due to iodine exposure, usually through skin absorption of iodine-containing disinfectants or intravenous administration of iodinated contrast agents. We report here a case of severe iatrogenic hypothyroidism with goiter and cholestasis, discovered six weeks after a contrast enema using sodium ioxitalamate, an iodinated contrast agent. Prematurity, intrauterine growth retardation, and enteral feeding intolerance could explain why this complication occurred after contrast enema. Our observations suggest that indications of contrast enema in neonates need to be carefully considered, and when necessary, thyroid function should be monitored, especially in very premature infants.

Betamethasone impairs cerebral blood flow velocities in very premature infants with severe chronic lung disease.

OBJECTIVE: To assess betamethasone (BM) effects on the cerebral hemodynamics of neonates with severe chronic lung disease (CLD). STUDY DESIGN: Intravenous BM was given once daily for 6 consecutive days to 12 infants (birth weight: 698 g [range, 650-884 g], gestational age: 25.3 weeks [range, 25-26.4 weeks]) at a postnatal age of 34 days (range, 28-36 days). Cerebral blood flow velocities (CBFVs) were recorded prospectively in the anterior cerebral artery (ACA) and the lenticulostriate artery (LSA) before, during, and after treatment, using Doppler flowmetry. RESULTS: The decrease in systolic and diastolic velocities was maximum on the 5th day, reaching 32% (95% confidence interval [CI], 23%-42%) and 58% (95% CI, 39%-64%) from baseline in the ACA, and 44% (95% CI, 29%-50%) and 57% (95% CI, 33%-66%) in the LSA, respectively. The resistance index (RI) increased significantly in both arteries during treatment. Return to baseline values was observed after BM was stopped. The change in velocities and RI was independent of arterial blood gas and blood pressure variations. CONCLUSIONS: BM decreased the CBFVs of premature infants, suggesting a vasoconstrictor effect in both superficial and deep arterial vessels. Caution is recommended when BM is used to treat preterm infants with severe CLD.

Multicenter assessment of ultrasound of the spermatic cord in children with acute scrotum.

PURPOSE: Intravaginal or extravaginal spermatic cord torsion is a diagnostic challenge for the surgeon and radiologist. Color Doppler sonography can be inaccurate, leading to dangerous false-negative results. To date, no single reliable test has been able to provide 100% diagnostic accuracy. The direct visualization of the twisted cord during emergency high resolution ultrasonography has been proposed to avoid systematic and abusive surgical exploration. The aim of this multicenter study was to assess the validity and reproducibility of high resolution ultrasonography based management of acute scrotum in children. MATERIALS AND METHODS: A total of 919 patients from 11 European university hospitals underwent color Doppler sonography and high resolution ultrasonography for acute scrotum between 1992 and 2005. The spermatic cord was studied along its complete length to detect a spiral twist. The surgical findings were correlated with the preoperative results. RESULTS: A total of 208 patients had spermatic cord torsion proved at surgery. Intratesticular vascularization was absent in the affected testis in only 158 cases (76%). In contrast, high resolution ultrasonography detected the twist as a snail shell-shaped mass, measuring 7 to 33 mm, in 199 patients (96%). High resolution ultrasonography revealed a linear cord for all other causes of acute scrotum (711 patients) with a specificity of 99%. The radiologist training level was the best predictive factor of high resolution ultrasonography reliability (p <0.05). CONCLUSIONS: High resolution ultrasonography based management of acute scrotum is reliable and reproducible. Thanks to its high sensitivity and specificity for the diagnosis of spermatic cord torsion, high resolution ultrasonography can significantly improve the management of acute scrotum in children.

[Congenital giant hydronephrosis: long-term results of primary neonatal nephroplication]. / Hydronéphrose géante du nouveau-né: résultats a long-terme de la néphroplicature primaire néonatale.

OBJECTIVE: Congenital giant hydronephrosis due to ureteropelvic junction obstruction is exceptional and treatment often requires nephrectomy of a poorly functioning kidney. However, a more conservative approach by nephroplication is also possible. The objective of this study was to evaluate the long-term functional outcome of these kidneys treated by nephroplication during the neonatal period. MATERIAL AND METHODS: From 1996 to 1998, 5 neonates with congenital giant hydronephrosis were managed in our department (3 antenatal diagnoses). The mean anteroposterior pelvic dilatation was 145 mm (range: 110-180 mm). All infants were treated by pyeloplasty with nephroplication, regardless of the preoperative ultrasound and scintigraphic appearance of the renal parenchyma. RESULTS: The mean follow-up was 9 years (range: 8-10 years). A marked initial reduction of global kidney volume was constantly observed (more than 50% of the initial volume). The mean relative renal function was 32.4% (range: 10-42%) without any residual obstruction. Renal growth was satisfactory in 4 cases (40 mm at 1 year, 72 mm at 6 years) with an atrophic kidney in 1 case. No child developed hypertension or elevated serum creatinine. CONCLUSION: Congenital giant hydronephrosis does not systematically justify primary nephrectomy even in the presence of a healthy contralateral kidney. Despite the pejorative initial ultrasound and scintigraphic appearance, which is always difficult to interpret, early nephroplication improves drainage of pyelocaliceal cavities, decreases the residual dilatation and allows significant nephron sparing in most of these children.

Brain ultrasonography in the premature infant.

Brain ultrasonography plays a central role in the detection and management of neonatal disease in the preterm infant. Although morphological study, using high-frequency transducers, remains the cornerstone of imaging, pulsed and colour Doppler scans provide additional information and improve the diagnostic and prognostic accuracy of ultrasonography. Particular features of normal brain US in the extremely preterm infant are reported. Cerebral haemorrhage and its different patterns (intraventricular haemorrhage and periventricular hemorrhagic infarction) are described. The value of Doppler techniques is emphasized, e.g. demonstration of coloured signal within the aqueduct of Sylvius, visualization of patency of the terminal veins, demonstration of Doppler spectrum fluctuations, recognition of low blood flow, and the detection of vasodilatation. The sonographic diagnosis of periventricular leucomalacia and its difficulties are documented. Some uncommon brain lesions of the premature infant are illustrated, e.g. gangliothalamic ischaemic damage, cortical necrosis, focal infarcts, etc. The importance of repeating the US examinations until near term is highlighted.

The value of colour Doppler ultrasonography for identification of crossing vessels in children with pelvi-ureteric junction obstruction.

BACKGROUND: Pelvi-ureteric junction (PUJ) obstruction is caused by the presence of an aperistaltic dysplastic segment at the PUJ. Besides this intrinsic aetiology, extrinsic abnormalities, mainly crossing vessels, may be an associated factor. OBJECTIVE: To determine the reliability of colour Doppler US in the detection of crossing vessels in children with surgically proven PUJ obstruction. MATERIALS AND METHODS: Forty-eight patients (50 kidneys) with PUJ obstruction, surgically treated from 1998 to 2001, were prospectively studied by colour Doppler US prior to open pyeloplasty. There were 33 boys and 15 girls (age 2 months-12 years; median 3.5 years). There were 24 right kidneys and 26 left kidneys. The indication for surgery was according to the usual criteria. The crossing vessel was considered as present when depicted on colour Doppler US at the PUJ. RESULTS: Colour Doppler assessment of the crossing vessels was correct in all but two patients. At surgery, a crossing vessel was found in 14 kidneys (i.e. 28%). Colour Doppler US results were correlated with intra-operative findings in 50 renal units. Surgically proven vessels in 14 kidneys were identified by colour Doppler US in 13, and not shown in 1. In PUJ obstruction without a crossing vessel ( n=36), US findings were concordant in 26, discordant in 8 and inconclusive in 2 (with kidney malrotation) cases. Colour Doppler US had a sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), and accuracy of 92.8%, 76.5%, 62%, 96.3% and 78%, respectively. The reliability of colour Doppler US was greatly improved with the increasing experience of the sonographer, as shown by the results of the last 2 years (26 kidneys):Se=100%, Sp=87.5%, PPV=81.8%, NPV=100%, accuracy=88.5%. CONCLUSIONS: Colour Doppler US is reliable in the detection of crossing vessels at the PUJ.

MRI of the fetal gastrointestinal tract.

OBJECTIVE: To determine the MRI patterns of the gastrointestinal (GI) tract in normal fetuses and some GI tract abnormalities. MATERIALS AND METHODS: A retrospective (1996-1998) and prospective (1999-2000) study of 48 fetal abdominal MRI scans was performed between 23 and 38 weeks of gestation. T1-weighted (T1-W) fast gradient-echo (Flash 2D) and T2-weighted (T2-W) HASTE sequences were obtained on a 1.5-T unit, in frontal and sagittal planes, after maternal premedication. Fresh meconium was also studied. RESULTS: Normal patterns (40 cases): the rectum was seen in all cases and exhibited meconium-like high signal on T1-W images and low signal on T2-W images. It was close to the bladder whatever the fetal gender with its cul-de-sac being at least 10 mm below the bladder neck. The large bowel had a same signal; the distal colon was demonstrated more frequently than the proximal colon. The small bowel was transiently hyperintense on TI-W images early in gestation and then hyperintense on T2-W images. Normal measurements were obtained. GI tract abnormalities (eight cases): cysts close to normal bowel ( n=2), atresias ( n=5; microcolon, dilated small bowel with abnormal signal, one with a meconium cyst) and a cloacal malformation with midgut malrotation ( n=1; abnormal liquid signal in the rectum separated from the bladder wall and colon located on the left side). CONCLUSIONS: MRI provided complete visualisation of the fetal GI tract, showed specific signal intensities, identified the level of an obstruction, detected a microcolon, and demonstrated communication between urinary and GI tracts. It shows great potential.