52 research outputs found
Meconium pseudocyst secondary to ileum volvulus perforation without peritoneal calcification: a case report
<p>Abstract</p> <p>Introduction</p> <p>A case of giant meconium pseudocyst secondary to ileum volvulus perforation is presented. Conventional radiographic features of meconium peritonitis with secondary meconium pseudocyst formation are well described. Our case is unusual in comparison to other cases reported in the literature and needs to be reported because the meconium pseudocyst presented without the typical ultrasound features (calcifications, polyhydramnios and ascites) and was initially identified as an abdominal mass.</p> <p>Case presentation</p> <p>We describe the case of a 29-year-old Caucasian woman in her third trimester of pregnancy, in which an abdominal mass was detected in the fetus. The newborn was diagnosed in the early neonatal period with meconium pseudocyst secondary to ileum volvulus perforation.</p> <p>Conclusions</p> <p>The prenatal appearance of a meconium pseudocyst can be complemented by other signs of bowel obstruction (if present) such as polyhydramnios and fetal bowel dilatation. This is an original case report of interest to all clinicians in the perinatology and fetal ultrasound field. We consider that the utility of this case is the recognition that a meconium pseudocyst might appear without the typical ultrasound features and should be considered as a differential diagnosis when an echogenic intra-abdominal cyst is seen.</p
Applying the ALARA concept to the evaluation of vesicoureteric reflux
The voiding cystourethrogram (VCUG) is a widely used study to define lower urinary tract anatomy and to diagnose vesicoureteric reflux (VUR) in children. We examine the technical advances in the VCUG and other examinations for reflux that have reduced radiation exposure of children, and we give recommendations for the use of imaging studies in four groups of children: (1) children with urinary tract infection, (2) siblings of patients with VUR, (3) infants with antenatal hydronephrosis (ANH), and (4) children with a solitary functioning kidney. By performing examinations with little to no radiation, carefully selecting only the children who need imaging studies and judiciously timing follow-up examinations, we can reduce the radiation exposure of children being studied for reflux
Constant-Power Power Supplies for the TESLA Modulators
For the TESLA Test Facility at DESY modulators, which generate high voltage, pulses of 130 kV with an electrical power of up to 16.8 MW are used. The pulses have a repetition rate of up to 10 Hz and a width of 1.7 ms. Since it is not possible to take the pulsed energy directly from the mains the required energy is stored in capacitor banks to be released during the pulse. Power supplies are needed to recharge the capacitor banks of the modulators without disturbing the mains. In particular the low repetition rate of the pulses has to be suppressed. Tobe independent from the repetition rate the power supplies have to operate in a constant power mode. The DC charging current into the capacitors decreases during the loading with the same factor with which the voltage increases. In this way the current taken from the threephase mains is constant. Different types of power supplies have been investigated at DESY and are described here. These types are antiductors with secondary diode bridges, switched mode power supplies, diode bridges plus series switched mode supplies, diode bridges with SCR bridges in sequential phase control
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