[Acute, atraumatic changes of the lower respiratory tract in the child in thoracic roentgen imaging. Recognition and appreciation of radiological changes]. / Akute, nicht traumabedingte Veränderungen des unteren Respirationstraktes des Kindes im Thoraxröntgen. Erkennen und Verstehen radiologischer Veränderungen.

The diagnosis of acute, non-traumatic diseases of the lower respiratory tract requires exact knowledge of the specific anatomy, physiology and pathology of the pediatric chest. The absolutely and relatively smaller airways, as compared with those of adults, and the undeveloped collateral ventilation result in radiological appearances that are unique in children. Viral pneumonia is predominant only in small children up to an age of 2 years. With increasing age, there is a higher incidence of bacterial pneumonia. The differentiation of viral and bacterial etiology of a pneumonia is not possible on the basis of chest radiographs. In acute pediatric imaging, possible aspiration of foreign bodies has to be considered. Since most foreign bodies cannot be detected radiographically, indirect features such as hyperinflation or mediastinal shifts have to be evaluated. Primary lung tumors are rare in children. More common are metastases with known primary tumors. Neuroblastoma or lymphomas may mimic intrapulmonary pathologies.

MR imaging of the ischiopubic synchondrosis.

The ischiopubic synchondrosis (IPS) is a temporary joint, occurring in childhood prior to fusion of the ischial and pubic bones. On conventional radiographs this tumor-like appearance is a well known normal anatomic variant, however, there are no reports in the literature of the appearance of IPS on MRI. Therefore the purpose of this study was to evaluate typical magnetic resonance features of the IPS. All pelvic MRIs from 1/1992 to 4/1998 of children ranging in age from 4 to 16 years, who were scanned for reasons other than bone disorders, were retrospectively investigated. Twenty-eight children were included and the morphologic appearance of IPS on MRI was evaluated. Seventeen (61%) of these 28 children had the following findings of IPS on MRI. Listed in order of frequency we found signal alteration of the ischiopubic fusion zone [hyperintense on T(2) with fat-saturation (89%) or STIR (74%), hypointense on T(1) (71%)], fibrous "bridging" (68%) [hypointense band on all sequences in perpendicular orientation to the axis of the inferior pubic ramus], fusiform swelling (68%), signal alteration of the adjacent soft tissue (57%) and irregular margins (56%). In 10 children contrast enhanced scans were available for evaluation, showing contrast enhancement of the bone marrow in 83.3% and of the adjacent soft tissue in 66.7%. Fusiform swelling of the ischiopubic fusion zone, signal alteration and contrast enhancement of both the bone marrow and the adjacent soft-tissue are characteristic features of the IPS on MRI, which may be due to mechanical stress at this temporary joint. These features are nonspecific and may resemble tumor, infection or trauma. Fibrous "bridging" was the only finding on MRI, which has not been described for any other entity and thus, it seems to be a characteristic MRI-feature.

[Chest X-ray of the neonate]. / Thoraxröntgen beim neonatologischen Patienten.

In diagnostic imaging of thoracic pathologies in mature and especially immature neonates, chest X-ray has a leading position. Profound knowledge of the normal chest X-ray and the potential physiological perinatal changes is the basic requirement for interpretation of the X-ray of a neonate. Childhood pathology: Many congenital and acquired diseases that the radiologist is faced with in neonatology are unknown in the imaging of adults. Many of these changes are life-threatening or may have an impact on the patient's future quality of life. Therefore early diagnosis in close cooperation with the paediatrician is essential. We give here an overview of the most important pathologic changes that the radiologist may be confronted with in daily routine.

["Lines and tubes" in neonatal intensive care patients]. / "Lines and Tubes" beim neonatologischen Intensivpatienten.

BACKGROUND: Central catheters in neonatological intensive care patients are used for the prolonged application of medication or parenteral infusions. Dislocations and septic and thromboembolic complications may occur. CONTROL OF POSITION: Radiologically, the correct position of the catheter must be proven. Dislocations or complications associated with central catheters must be diagnosed. For catheter monitoring plain film radiographs are the first line of investigation; however, sonography may be of additional assistance. Angiographic techniques should only be performed when conventional noninvasive methods do not supply satisfactory results. Special knowledge is necessary for monitoring catheters that are set via the umbilical artery or vein. The radiological applications for catheter monitoring in the neonate intensive care unit are discussed in this article.

Recurrent suppurative thyroiditis due to pyriform sinus fistula: a case report.

Acute suppurative thyroiditis is a rare disease, particularly in childhood. We present a case with recurrent acute suppurative thyroiditis due to a pyriform sinus fistula originating from the fourth branchial pouch. The typical symptoms of a pyriform sinus fistula are recurrent left-sided pain and swelling of the neck with signs of acute bacterial inflammation. Diagnosis should be made by high resolution ultrasound, barium meal studies and endoscopic examination. During acute exacerbations treatment with antibiotics is indicated, but permanent cure can only be attained by complete fistulectomy.

[Recurrent renal vein thrombosis in a premature infant. Doppler ultrasound diagnosis and follow-up]. / Zweizeitige Nierenvenenthrombose bei einem Frühgeborenen. Dopplersonographische Diagnose und Verlaufskontrolle.

Renal vein thrombosis (RVT) is a rare disorder in neonates. Early diagnosis is mandatory since immediate thrombolytic therapy favours prognosis. Our case report describes RVT demonstrated by Duplex Doppler Ultrasound. A possibly characteristic sequence of changes in the echogenicity of the renal parenchyma and in the Duplex Doppler flow pattern of the renal arteries could be found.

[Ultrasound monitoring of the umbilical artery catheter. A case of a newborn infant with recurrent hypoglycemia]. / Sonographische Lagekontrolle des Nabelarterienkatheters. Fall eines Neugeborenen mit rezidivierenden Hypoglykämien.

Hypoglycaemia in neonates can be caused by malposition of the umbilical artery catheter (UAC). If the tip of the umbilical arterial catheter is located next to the origin of the great abdominal vessels glucose infusion is mainly directed into the coeliac trunk and superior mesenteric artery. Direct stimulation of the pancreatic gland might then result in hyperinsulinaemic hypoglycaemia. Generally, UAC position is controlled by x-ray. When using ultrasound for location of the UAC the exact topography and especially the relation of the tip of the UAC to the great vessel lumina can be documented precisely.

Sonographic detection of internal jugular vein thrombosis after central venous catheterization in the newborn period.

We sonographically investigated the internal jugular veins of 40 children who had undergone catheterization of the vein (group A: silastic catheter, n = 24; group B: polyurethane catheter, n = 16) in the neonatal period. The average age at catheter implantation was 43 +/- 73 days, the average birthweight 2414 +/- 1145 g, and the average gestational age 34.8 +/- 5.0 weeks. We performed follow-up longitudinal and transverse high resolution sonographic scans including routine examination of the contralateral jugular vein at a mean age of 3.7 +/- 1.5 years. In group A thrombotic alterations were detected in 8 aut of 24 patients. In three of these patients we found mild clinical symptoms. In group B thrombotic alterations were detected in 1 aut of 16 patients without clinical symptoms. Mean birthweight (1815 versus 3313 g) and mean gestational age (32.3 versus 38 weeks) were significantly lower and indwelling time of the catheters (18 versus 11 days) was significantly longer in group A. Our results indicate that jugular vein thrombosis is a frequent long-term complication in neonates after jugular vein catheterization. High resolution ultrasonography is an adequate method for detecting jugular vein thrombosis and should therefore routinely be performed for long-term follow-up.

[Pseudotumor of the orbit in pediatrics. Diagnostic imaging]. / Pseudotumor der Orbita in der Pädiatrie. Bildgebende Diagnostik.

Orbital pseudotumor is an inflammatory lesion with increased orbital mass and a typical rapid onset. It is very uncommon in children. Diagnosis is difficult and there is no uniform procedure. Two patients with different forms of this entity are presented, and their clinical symptoms and CT and ultrasonographic features are discussed. We found the CT and US findings to be important for the differential diagnosis. Therefore, these diagnostic modalities should be applied immediately on the onset of typical clinical symptoms, because the condition can result in ophthalmoplegia and amaurosis if not treated at once.

[Importance of early diagnosis of urinary tract infections in childhood. Results of a retrospective study of children with vesico-uretero-renal reflux]. / Bedeutung der Frühdiagnostik bei Harnwegsinfektionen im Kindesalter. Ergebnisse einer retrospektiven Untersuchung von Kindern mit vesiko-uretero-renalem Reflux.

Urinary tract infections (UTI) in children are common. In the case of high grade vesico-ureteric-renal reflux (VUR) or urinary tract obstruction the abnormality may lead to end-stage renal failure. An early evaluation and adequate therapy after UTI are mandatory. Between 1980 and 1987 we evaluated 63 children with VUR. The symptoms of UTI are variable and age-dependent. Only in 13% of the children the urinary tract was evaluated after their first UTI. In 70% of the cases there were more than 1, mostly multiple UTI. The remaining 17% were admitted for other reasons. The relation boys to girls was 1:2. In boys the diagnosis of VUR was made earlier than in girls: 57% of boys and 17% of girls in their first year of life. In 24% of the boys and in 36% of the girls VUR was found between the 5th and 15th year of life. In the case of high grade reflux (IV-V) the kidneys showed heavy damage, loss of function and hypertension at the time of diagnosis. The aim must be early diagnosis and adequate therapy to prevent avoidable damages.

[Ultrasound image of an unusual intrahepatic site of a bile duct cyst]. / Das sonographische Bild einer ungewöhnlichen intrahepatisch gelegenen Gallenwegszyste.

An intrahepatic cyst was found ventral and cranial to the gallbladder without choliangectasy in an infant of 8 months of age. Final diagnosis of a bile duct cyst was arrived at intraoperatively. The article discusses the possible aetiology, non-invasive diagnosis and sonographic differential diagnosis. Sonography is discussed as the method of choice in assessing intrahepatic and extrahepatic cysts and the bile ducts.

Color-coded Doppler evaluation of cholecystic varices in portal hypertension.

A 11-year-old white girl presented with a diagnosis of thrombosis of the portal vein after newborn septicemia. Duplex sonography revealed significant narrowing of the portal vein and its right and left branches. A Doppler signal could only be obtained in certain short segments of the portal vein and indicated hepatopetal flow. Color-coded Doppler sonography showed extensive varicose veins in the gallbladder with a bigger draining vessel running to the porta hepatis. Documentation of varices like those in the gallbladder wall confirms the diagnosis of portal hypertension and may increase the sensitivity of Doppler sonography. Color mapping has the potential to detect unexpected flow and to analyze blood flow to better advantage.

Cerebral blood flow in newborn infants with and without mechanical ventilation.

The influence of mechanical ventilation with low mean airway pressure (MAP) on cerebral blood flow (CBF) veolocity in newborn infants was assessed in fifteen ventilated infants by Duplex Doppler Sonography (Duplex DS). As a control, CBF velocities were examined in 15 age and weight matched non-ventilated infants. For quantitation, maximal systolic velocity, enddiastolic velocity and the semiquantitative Pourcelot index were determined as representative flow variables. There was no significant difference of these flow variables between ventilated and non-ventilated infants. The pH, pO2 and pCO2 did not differ significantly between the two groups and there was no correlation between the flow variables, pH, pO2, pCO2 or MAP. Mechanical ventilation with low MAP is not associated with adverse effects on cerebral hemodynamics in newborn infants when significant alterations of the blood gases are avoided.

Portal venous blood flow in cystic fibrosis: assessment by Duplex Doppler sonography.

Changes of portal venous hemodynamics were investigated in 32 patients with cystic fibrosis (CF) with a mean age of 11.6 years. Hepatic profile of these patients included total bilirubin and albumin together with determination of size and echogenicity of the liver and spleen, determination of the diameter of the portal vein by real-time sonography and quantitation of flow volume of the portal vein using Duplex Doppler sonography. As a control, 35 age matched healthy children were also examined. Diameter of the portal vein was significantly increased in CF patients versus controls. Comparison of the mean flow volume of the portal vein showed a significant increase in CF-patients over 12 y old versus controls. In patients less than 12 y no significant difference of flow volume of the portal vein between CF-patients and controls was noted. The increase of diameter and flow volume of the portal vein suggest an adaptive mechanism in the pressure-volume relationship of the portal venous system in patients with CF.

[Changes in renal echogenicity in pediatric obstructive uropathies]. / Die Anderungen der renalen Echogenität bei kindlichen obstruktiven Uropathien.

Renal cortical echogenicity of 40 children with obstructive uropathies was analysed in relation to the grade of obstruction and thinning of the renal cortex. In 35 percent of the children an increase in echogenicity was noted. The increase in cortical echogenicity paralleled the grade of dilatation of the intrarenal collecting system and the grade of thinning of the renal cortex. Evaluation of the cortical echogenicity should be integrated into the primary diagnostic setup as well as into the follow-up of children suffering from obstructive uropathies.

[Diffuse xanthogranulomatous pyelonephritis in childhood]. / Diffuse xanthogranulomatöse Pyelonephritis im Kindesalter.

Xanthogranulomatous pyelonephritis is a rare disease and rare cause of suppurative proliferative pseudotumor in children. An accurate diagnosis is difficult because of its clinical, radiological, sonographical and pathologic-anatomical similarities to renal tuberculosis. After removing the diseased kidney the prognosis is excellent. A 6-year old boy with xanthogranulomatous pyelonephritis is reported.

Acute renal transplant rejection in children: assessment by Duplex Doppler sonography.

Over a two year period 74 consecutive Duplex Doppler scans were performed in 23 children with renal allografts and were compared to the Doppler sonographic findings in orthotopic kidneys of 25 age matched healthy controls. The Doppler waveforms of renal arterial flow were analyzed qualitatively assessing systolic and diastolic flow amplitudes, for quantitation the Pourcelot index (PI) was used. There was no variation between the Doppler waveforms in recipients with normal allograft function and healthy controls. In 12 patients with biopsy proven acute rejection a decrease or absence of the diastolic flow amplitude was noted, resulting in increased pulsatility of the Doppler waveform. The mean PI in acute rejection differed significantly from the mean PI in normal allograft function. Duplex Doppler sonography is a useful imaging modality in the differentiation between acute rejection and normal allograft function and should therefore be integrated in the screening of children after renal transplantation.