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.

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.

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.