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Title: Disposal of HLW and ILW/LLW at the same site: challenges in an international contextAuthors: Maurer-Rurack, U.*, Poller, A., Hardie, S., Poppei, J., Voss, M. **, Smith, P. **** Federal Office for the Safety of Nuclear Waste Management (BASE), Berlin, Germany** CSD Ingenieure AG, Switzerland*** Safety Assessment Management GmbH, Switzerland Abstract:Germany is looking for the site with best possible safety for an HLW (high level waste) repository. In the site selection procedure of Germany three host rocks: rock salt, clay and crystalline rock are considered. In accordance with §1 (6) of the StandAG (German Site Selection Act), an additional disposal of ILM/LLW (intermediate level/low level waste) might be allowed at the same site, provided that its characteristics satisfy the best possible safety criteria for the sole disposal of HLW waste. This point will be addressed within the framework of preliminary safety investigations pursuant to §27 (5) of the StandAG in the individual phases of site selection process for the HLW repository, according to the current state of science and technology.The GemEnd research project (2022, in press) investigates the possible mutual influence of these different types of repositories at the same site and the resulting safety-relevant consequences for the HLW repository system in Germany.This contribution provides an overview of the currently existing international disposal programs of non-heat-generating waste (ILW/LLW) and heat-generating waste (HAW) at the same site in the following countries: Belgium, France, Finland, Germany, Japan, Sweden, Switzerland and the United Kingdom.The IAEA (International Atomic Energy Agency) also considers co-disposal of HLW and ILW/LLW as an option that has advantages over separate repositories. But particular critical interactions caused by gas formation and gas transport as well as interactions of cementitious materials with other engineered components and the host rocks should not be forgotten (IAEA 2009, 2018).On this basis, existing international disposal programs for HLW and ILW/LLW at the same site are compared with each other. Important similarities and differences for the transferability of the findings to the site selection procedure in Germany are presented. Finally, the approach of other countries can contribute to a better assessment of the safety implications in Germany.

The Federal Office for the Safety of Nuclear Waste Management (BASE – Bundesamt für die Sicherheit der nuklearen Entsorgung) is the German federal regulatory authority for radioactive waste disposal. It supervises the German site selection process and is responsible for the accompanying public participation. Task related research is an integral part of BASE's activities. The projects MessEr and übErStand compiled the state-of-the-art science and technology regarding surface based exploration methods suitable for addressing the criteria and requirements specified in the German Site Selection Act. The results support BASE to review and define the surface-based exploration programs to be executed by the national implementer BGE (Bundesgesellschaft für Endlagerung mbH). To support BASE in reviewing the application of the exclusion criteria “active fault zones” according to the Site Selection Act, the project KaStör reviewed the current knowledge on active faults and fault zones in Germany and recommends methodological approaches to date and identify the activity of faulting. For the time being, the Site Selection Act defines 100 ∘C as a draft limit on the temperature at the outer surface of a repository container for all host rocks. The project Grenztemperatur studied the temperature dependency of the different thermal-hydraulic-mechanical-chemical/biological (THMC/B) processes according to available features-events-processes (FEP) catalogues for rock salt, clay stone, and crystalline rock and describes ways to defining host rock specific maximum temperatures based on specific disposal and safety concepts. Safety oriented weighting of different criteria and comparison of different potential regions and sites are key challenges during the siting process. The project MABeSt studied and reviewed methodological approaches to this weighting and comparison problem with special emphasis on multi criteria analysis (MCA) and multi criteria decision analysis (MCDA). A key requirement for safe geological disposal of nuclear waste is barrier integrity. The project PeTroS performed the first triaxial flow-through experiments on natural rock salt samples at disposal relevant p−T conditions and studied potential percolation mechanisms of fluids within rock salt. The data substantiate that the minimum stress criterion and/or the dilatancy criterion are the prime “percolation thresholds” in rock salt. The research results support BASE in fulfilling its tasks as national regulator according to state-of-the-art science and technology and are also relevant to other stakeholders of the siting process.

Background Bronchopulmonary dysplasia (BPD) is the most frequent chronic lung disease in infancy and is associated with neonatal comorbidity and impairment in pulmonary and neurodevelopmental (ND) long‐term outcome. Methods This was a retrospective, single‐center, cohort study to compare a cohort of very preterm infants (gestational age [GA], 24+0–28+6 weeks) with BPD (n = 44), with a cohort of GA‐matched preterm infants without BPD (n = 44) with regard to neonatal morbidity, incidence of lower respiratory tract infection (LRTI), ND outcome and growth to 2 years' corrected age (CA) and preschool age. Results Bronchopulmonary dysplasia (incidence, 11.3%) was associated with a higher rate of neonatal pneumonia (26% vs 7%, P = 0.001), longer total duration of mechanical ventilation (mean days, 21 vs 13, P < 0.001), and a higher rate of pulmonary hypertension (20.5% vs 0%, P = 0.002) and of severe retinopathy of prematurity (13.6% vs 0%, P = 0.026). Incidence of LRTI was significantly higher in the BPD infants (50% vs 26%, P = 0.025). ND outcome did not differ between the two groups. Growth at neonatal intensive care unit discharge was similar. In the BPD cohort, rate of weight < 10th percentile was higher at 2 years' CA (52% vs 30%, P = 0.041) and rate of head circumference < 10th percentile was higher at preschool age (59% vs 27%, P = 0.028). Conclusion Neonatal respiratory morbidity was significantly higher in the BPD cohort, but long‐term ND outcome did not differ. Infants with BPD had poorer growth.

The Site Selection Act stipulates a precautionary temperature limit of 100 ∘C on the outer surface of the containers with high-level radioactive waste (HLRW) in the final disposal site. This precautionary temperature limit should be applied in preliminary safety analyses provided that the maximum physically possible temperatures in the respective host rocks have not yet been determined due to pending research. Increasing temperatures in the deep geological underground, caused by the heat generation of the HLRW, can trigger thermal, hydraulic, mechanical, chemical and biological processes (THMCB) in the respective host rocks of a final disposal site and thus endanger safety. Furthermore, high temperatures may hamper the feasibility to retrieve and recover HLRW from a final disposal site. Such processes are described in detail in databases for features, events and processes (FEP) databases. Single components or barriers of a final disposal facility may require specific design temperatures for the preservation of their features once a concept for long-term safety of a final disposal site is established; however, the interactions of all relevant processes of a concept for a final disposal site must be considered when a specific temperature limit for the outer surface of the containers is derived. This temperature limit may vary for particular safety and final disposal concepts in the host rock: salt, clay and crystalline rock. The conclusion is that temperature limits regarding the outer surface of the containers should be derived specifically for each safety and disposal concept and should be supported by a solid safety analysis. Temperature limits without reference to specific safety concepts or the particular design of the final disposal site likely narrow down the possibilities for optimisation and could adversely affect the site selection process in finding the best suitable site.

The Federal Republic of Germany has decided to dispose its high-level radioactive waste in deep geological formations. Three types of host rock are considered: rock salt, clay rock and crystalline rock. The Site Selection Act (StandAG1), which came into effect on the 16th of May 2017, defines the successive steps of the repository siting process, which has to ensure the best possible safety conditions for a period of one million years. Based on precaution considerations, the StandAG (§27 (4) StandAG) sets a preliminary temperature limit of 100°C at the outer surface of a repository container for the preliminary safety assessment.This contribution provides an overview about the state of the scientific and technical knowledge on the limiting temperatures in the repository site selection process of Germany. It also illustrates the different treatments of the definition of temperature limits within other European siting processes. The findings highlight that, in Europe, the proposed criteria which consider temperature at the outer surface of a repository container get more and more into focus of research and discussion especially for the three different types of host rocks.After presenting the national regulatory frameworks, this contribution summarizes how the European countries address the different temperature related issues for their site selection, their repository concepts and how in turn these all can influence the German safety case strategy for the German site selection. Not at least, links to site selection criteria in other countries (e.g. USA, Japan, Russia) are provided.Reference1 StandAG: Standortauswahlgesetz vom 5. Mai 2017 (BGBl. I S. 1074), das zuletzt durch Artikel 2 Absatz 16 des Gesetzes vom 20. Juli 2017 (BGBl. I S. 2808) geändert worden ist.

The German Site Selection Act (Standortauswahlgesetz – StandAG) defines the search for and selection of the national German site with best possible safety for a disposal facility for high-level radioactive waste. The Federal Office for the Safety of Nuclear Waste Management (BASE) is the federal regulatory authority for radioactive waste disposal. BASE supervises the site selection process for a repository for high-level radioactive waste and is responsible for the accompanying public participation. To fulfill its tasks according to the state of science and technology, task related research forms an integral part of BASEs activities. Current research activities in the context of the site selection process address geoscientific questions, methodological aspects of the implementation of the site selection process, and public participation aspects. This contribution provides an overview on the current geoscientific and methodological research activities of BASE.According to § 16 StandAG , the national implementer (Bundesgesellschaft für Endlagerung mbH) has to execute surface-based exploration and BASE has to review and define the respective exploration program. Therefore, the two projects MessEr and übErStand compiled state of science and technology with regard to surface based exploration methods. The foci were on methods suitable for addressing the criteria and requirements set out in the German Site Selection Act.The project KaStör reviewed the current knowledge on active faults and fault zones in Germany and studied methodological approaches to date and identify the activity of faulting. The results support BASE to review the application of the exclusion criteria for areas with “active faults zones” according to § 22 (2) StandAG.For the time being, § 27 (4) StandAG defines 100 °C as precautionary maximum temperature at the outer surface of waste canisters for all host rocks. The project Grenztemperatur compiled and studied the temperature dependency of the different THMC/B processes according to available FEP catalogues for rock salt, clay stone, and crystalline rock. The project also identified open and pending research questions and describes ways to define host rock specific maximum temperatures based on specific disposal and safety concepts.During the site selection process, safety oriented weighting of different criteria and comparison of different potential regions and sites have to be performed. The project MaBeSt studied and reviewed methodological approaches to this weighting and comparison problem with special emphasis on multi criteria analysis (MCA) and multi criteria decision analysis (MCDA).Key requirement for safe geological disposal of nuclear waste is barrier integrity. The project PeTroS experimentally studied potential percolation mechanisms of fluids within rock salt at isotropic conditions at disposal relevant pressures and temperatures.

The purpose of this study is to describe features of cystic periventricular leukomalacia (PVL) in a large consecutive cohort study including long-term neurodevelopmental follow-up. We performed a retrospective single-centre cohort study including all preterm infants ≤35 weeks of gestational age with PVL diagnosed by ultrasound scans (US) from a tertiary care university hospital between 1988 and 2012. The majority of 160 consecutively diagnosed cases had a gestational age between 28 and 32 weeks (60.6 %), and male sex was predominant (60.6 %). The most common associated clinical findings included respiratory distress syndrome, preterm premature rupture of the membranes, and chorioamnionitis (57.5, 49.4, and 39.4 %, respectively). Infants presented with apnoeas in 66.3 and neonatal seizures in 23.1 %. Any kind of respiratory support was present in 75.0 %. Associated low-grade intraventricular haemorrhage was evident in 33.1, high-grade haemorrhage in 9.4 %. Cysts were located on both hemispheres in 75 % and PVL grades 3 and 4 were predominant (75.6 %). Neurodevelopmental follow-up of 146 cases at a median age of 72 months revealed normal development in 11.0, mental retardation in 50.0, and cerebral palsy in 83.6 %. Visual impairment was diagnosed in 21.9 % and hearing impairment in one case. A quarter of cases (27.4 %) developed seizure disorders. Outcome data were significantly better in unilateral compared to bilateral PVL. Long-term neurodevelopmental outcome of bilateral PVL always was adverse and different from unilateral PVL. The latter might be negatively influenced by associated intra- and periventricular haemorrhages.

The objective of this study was to investigate neurological short-term effects of craniosacral therapy as an ideal form of osteopathic manipulative treatment (OMT) due to the soft kinaesthetic stimulation. Included were 30 preterm infants, with a gestational age between 25 and 33 weeks, who were admitted to the neonatal intensive care unit of the University Hospital of Graz, Austria. The infants were randomized either into the intervention group (IG) which received standardised craniosacral therapy, or the control group (CG) which received standard care. To guarantee that only preterm infants with subsequent normal neurodevelopment were included, follow up was done regularly at the corrected age (= actual age in weeks minus weeks premature) of 12 and 24 months. After 2 years 5 infants had to be excluded (IG; n = 12; CG: n = 13). General Movements (GMs) are part of the spontaneous movement repertoire and are present from early fetal life onwards until the end of the first half year of life. To evaluate the immediate result of such an intervention, we selected the General Movement Assessment (GMA) as an appropriate tool. Besides the global GMA (primary outcome) we used as detailed GMA, the General Movement Optimality Score (GMOS- secondary outcome), based on Prechtl’s optimality concept. To analyse GMOS (secondary outcome) a linear mixed model with fixed effects for session, time point (time point refers to the comparisons of the measurements before vs. after each session) and intervention (IG vs. CG), random effect for individual children and a first order autoregressive covariance structure was used for calculation of significant differences between groups and interactions. Following interaction terms were included in the model: session*time point, session*intervention, time point*intervention and session*time point*intervention. Exploratory post hoc analyses (interaction: session*time point*intervention) were performed to determine group differences for all twelve measurement (before and after all 6 sessions) separately. Between groups no difference in the global GMA (primary outcome) could be observed. The GMOS (secondary outcome) did not change from session to session (main effect session: p = 0.262) in the IG or the CG. Furthermore no differences between IG and CG (main effect group: p = 0.361) and no interaction of time*session could be observed (p = 0.658). Post hoc analysis showed a trend toward higher values before (p = 0.085) and after (p = 0.075) the first session in CG compared to IG. At all other time points GMOS were not significantly different between groups. We were able to indicate that a group of “healthy” preterm infants undergoing an intervention with craniosacral therapy (IG) showed no significant changes in GMs compared to preterm infants without intervention (CG). In view of the fact that the global GMA (primary outcome) showed no difference between groups and the GMOS (detailed GMA-secondary outcome) did not deteriorate in the IG, craniosacral therapy seems to be safe in preterm infants. German Clinical Trials Register DRKS00004258 .

Objective : To assess neonatal outcome and 2-year follow-up of pregnancies complicated by second trimester preterm premature rupture of membranes (PPROM). Methods : A retrospective review of obstetric and neonatal records for 87 pregnancies (56 singletons, 6 twins, 1 triplet) with PPROM between 14 + 0 and 24 + 6 weeks of gestation. Patients received antibiotics and steroids for fetal lung maturity once they reached 24 weeks of gestation. Placentas were examined histopathologically. Surviving infants were followed-up at 2 years of age. Results : Median latency from PPROM to delivery was 4 days. Survival rate of 56 singletons was 45% (25/56); and 13 died in hospital. Survival rate of infants discharged from hospital was 23% (12/56). Chorioamnionitis was seen histologically in 42% (5/12) of surviving infants compared with 92% (12/13) of those that died in hospital. Of the 12 surviving infants, 50% had a normal neurological and developmental outcome at 2 years of age. Conclusion : Gestational age, birth weight, and histologic chorioamnionitis have prognostic importance in pregnancies complicated by PPROM. Surviving infants have a 50% chance of achieving an adequate health status at 2 years of age.

Selected habitats in Berlin (Germany) were investigated with a focus on the diversity of flora and land use patterns. On the one hand, the correlation between the number of plant species and the diversity of land use patterns is shown for a transection running from the center to the outskirts of Berlin. The greatest variety of land use patterns and the highest number of species per square kilometer can be found in the transition zone between the city center and the outskirts where urban structures are closely associated with open spaces like large parks, urban forests, and larger wastelands. In accordance with the intermediate disturbance hypothesis, the mosaic of land use patterns in the transition zone with moderate frequencies or intensities of disturbance positively affects habitat diversity, as well as overall species diversity on the landscape level. Furthermore, in residential areas built in the 1920s and 1930s, the flora was studied from both a historical and a present-day perspective in order to assess the diversity of wild-growing indigenous and non-native plant species, wild-growing ornamental plant species, and planted trees. The highest numbers of species were recorded in less intensively managed habitats. In addition to structural factors (e.g. land use patterns) determining the diversity of flora and vegetation in cities, this study also demonstrates the importance of the historical factor for biodiversity. The differences in land use throughout the last 70 years (pre- and post-World War II era) can be seen as an explanation for the relatively high diversity of the flora in the investigated residential areas. Cities have to be regarded as a new type of environment with species compositions and habitats peculiar to urban-industrial areas. Future research and planning of nature conservation and sustainable development of urban-industrial areas should take the biological diversity in cities fully into account. Recommendations are given for the maintenance and development of biological diversity in cities, focussing on landscape and habitat as well as species diversity.

Cerebral palsy is a non-progressive disorder of the developing brain with different etiologies in the pre-, peri- or postnatal period. The most important of these diseases is cystic periventricular leukomalacia (PVL), followed by intra- and periventricular hemorrhage, hypoxic-ischemic encephalopathy, vascular disorders, infections or brain malformations. The underlying cause is always a damage of the first motor neuron. Prevalence of cerebral palsy in Europe is 2-3 per 1000 live births with a broad spectrum in different birth weight groups. Our own data concerning only pre-term infants in the NICU with birth weight below 1500 g (VLBW) are between 10%-20%. Established classical treatment methods include physiotherapy (Bobath, Vojta, Hippotherapy), methods of speech and occupational therapists (Castillo-Morales, Sensory Integration) and other therapeutical concepts (Peto, Affolter, Frostig).

About 1 out of 100 full term born infants develops intracranial hemorrhage. The study represents an analysis of intracranial hemorrhage over a ten-years period. Diagnosis was based on ultrasound scan. A division into five major bleeding types was done according to the location of the hemorrhage. The neurological outcome was reviewed. Patients were classified into three groups according to their neurological outcome: normal neurological development, mild neurological impairment, and severe neurological impairment. Between 1989-1999, 2019 full-term newborn infants were treated at the neonatal intensive care unit in Graz. 54 of them (2.7%) developed intracranial hemorrhage, of whom 13 (24%) suffered from subdural hemorrhage, 1 (2%) from primary subarachnoid hemorrhage, 14 (26%) from hemorrhage within the choroid plexus, 6 (11%) from intraventricular hemorrhage grade I (IVH I), 11 (20%) from intra- and periventricular hemorrhage (IVH III/PVH), 6 (11%) from hemorrhage within the basal ganglia, and 3 (6%) from intracerebellar hemorrhage. Considering the neurological outcome, 34 (63%) were diagnosed as being developed normally, 15 (28%) developed any neurological impairment, 3 (5%) died, whereas 2 (4%) did not participate our follow up program.

Part of this investigation is the flora of three different urban land-use types which represent typical biotope characteristics of Berlin and Potsdam. The majority of these urban land-use types is located in the former GDR territory of East Berlin and Potsdam, which were almost unexplored and are therefore of special botanic interest. The focus lies on the inventory of wild-growing vascular plants, their diversity, richness, and value for nature conservation. The first investigated land-use type are the landscape parks of Potsdam with their plant communities of meadows and lawns which differ from many other grasslands of today in having unique plant species due to their historic garden design and the continuous way of extensive garden management. Second, the residential areas of the 20/30s in Berlin and their diversity of wild-growing vascular plants and planted trees which reflect the original garden management and the gardening traditions of this decade are presented. The third urban land-use type is the area of the Berlin wall with urban wasteland communities. It will be shown that also in the inner city with a high population density a special variety of species makes urban wastelands worthy for nature conservation.

Purpose: To describe neonatologic complications in and long-term sequelae of extremely low birth weight (ELBW) infants. Material and Methods: From 1992 and 1994 82 infants were born between 24 and 27 weeks of gestation or with a birth weight ≤900 g. Perinatal mortality, neonatal complications and physical and neurological status at age 2-4 years were assessed. Results: The mean (± SD) gestational age was 26.3 ±1.4 weeks, the mean birth weight was 900±207 g. The overall perinatal mortality was 27/82 (33%). 13 of these infants (16%) died prenatally and 14/82 (17%) died in the neonatal period. Among 64 vaiable infants the neonatal mortality was 11/64 (17%) and decreased from 4/7 (57%) at 24 weeks to 2/22 (9%) at 27 weeks. Survival rates correlated significantly (p = 0.03) with gestational age but not with birth weight. Causes of death were cerebral haemorrhage (5/64, 8%), extreme prematurity (4/64, 6%) or sepsis (2/64, 3%). 31/64 infants (48%) had respiratory distress syndrome with a mean duration of assisted ventilation of 21±12 days. 24/64 infants (38%) had intraventricular bleeding and 25 (39%) had signs of bacterial infection. The mean hospital stay was 94±30 days. At age 2-4 years 26/51 infants were developed appropriately for age. 12/51 (24%) had severe, 3/51 (6%) moderate and 10/51 mild impairment. The incidence of impairment was not associated with gestational age and not higher in infants 750 g. Conclusion: In our series the neonatal mortality rate of ELBW infants was associated with gestational age but not birthweight. The risk of neonatal mortality declined with increasing gestational age but the risk of permanent impairment was associated with neither gestational age nor birthweight.

In a pilot study, alterations of polymorphonuclear neutrophil function during systemic thrombolysis in acute myocardial infarction have been investigated in humans. The following parameters of neutrophil function were measured before and at 15 and 45 minutes after initiation of systemic thrombolysis with a recombinant tissue-type plasminogen activator in 20 patients with acute myocardial infarction: (1) neutrophil adhesion and (2) neutrophil activation. During systemic thrombolysis a significant decrease was observed in neutrophil adhesion (5.5+/-6.4 to 3.2+/-3.3; p0.05), in phagocyting neutrophil activation (39+/-18 to 25+/-14%; p0.05), and in resting neutrophil activation (9+/-7 to 3+/-4%; p0.05). Successful reperfusion coincided with a significantly higher reduction of phagocyting neutrophil activation (40+/-14 to 20+/-12% vs. 39+/-24 to 26+/-19% in unsuccessful reperfusion; p0.05), and of neutrophil adhesion (6.2+/-5.7 to 2.7+/-3.0 vs. 4.1+/-3.8 to 3.5+/-4.0 in unsuccessful reperfusion; p0.05) during thrombolysis. Systemic thrombolysis in acute myocardial infarction is accompanied by a reduction in neutrophil adhesion and activation dependent on thrombolytic success.

Assessment of neurologic and developmental outcome at 2 years age of infants with gestational age (GA)27 weeks, born between 1996-2001.A total of 110 live-born preterm infants with GA27 weeks.Main outcome criterions: Neurologic examination (according to Touwen) and classification of cerebral palsy by using the Gross Motor Function Classification System (GMFCS) at the corrected age of 1 and 2 years; assessment of mental and psychomotor development by using the Griffith Mental Development scales at the corrected age of 2 years; growth assessment at birth, 1 and 2 years.Mortality was 52%. Regular follow up was performed in 48 (91%) of the 53 surviving infants. Neurologic outcome: at 1 year age: 2% nonambulant cerebral palsy, 25% mild neurologic signs and 73% normal; at 2 years age: 4% nonambulant cerebral palsy, 2% ambulant cerebral palsy, 4% mild neurologic signs and 90% normal neurology. Developmental outcome at 2 years age: 40% DQ-1 SD, 6% DQ between -1 SD and -2 SD (mild delay), 35% DQ between -2 SD and -3 SD (moderate delay) and 19% DQ-3 SD (severe delay). Overall disability was found in 64%, severe disability in 27% of the infants. Profound growth failure in weight and head circumference3rd centile at 2 years age was recorded in 39 and 19% of the infants, respectively.Developmental delay is very common in preterm infants27 GA and exceeds the number of neurological disabilities (including cerebral palsy).

Transient periventricular echodensities (PVE) in preterm infants affect neurodevelopmental outcome.To correlate the duration and grading of PVE with neurodevelopmental outcome.A retrospective, single-centre cohort study of infants with PVE diagnosed by ultrasonography from 1995 to 2000 with blinded grading and recognition of duration of PVE.A total of 72 infants (median gestational age 32 weeks, median birth weight 1,668 g) were diagnosed as having PVE. Minor neurological abnormalities were diagnosed in seven (10%), cerebral palsy in six (8%), developmental delay in seven (10%), and mild mental retardation in two (3%) of the infants. Differences regarding adverse outcome were not significant between infants with severity grade 1 compared to severity grade 2 (16% and 22%, respectively). There was a significant increase in adverse neurodevelopmental outcome with increasing duration of PVE. Of 33 infants with duration of PVE7 days, 1 (3%) had an adverse neurodevelopmental outcome, compared to 6 (24%) of 25 infants with a duration of PVE of 7-14 days, and 6 (43%) of 14 infants with a duration of PVE14 days (P0.002, RR 7.920, 95% CI 1.017-61.661; P0.001, RR 14.143, 95% CI 1.871-106.895, respectively).The duration, but not the grading, of transient PVE was significantly correlated with neurodevelopmental outcome.

Drainage problems due to catheter malpositioning are acutely life-threatening in patients undergoing extracorporeal membrane oxygenation. In order to reduce these complications we introduced sonographically guided catheter positioning. We compare the outcome in a group of patients with blind cannula positioning to that in a group with sonographically guided catheter positioning. Our results show that neonates and young infants especially are at high risk of drainage problems due to catheter malposition and that their outcome could be markedly improved by introducing sonographically guided cannula insertion.

Sonography was compared to pH-metry and/or oesophagomanometry to evaluate the accuracy of sonography in the early diagnosis of gastro-oesophageal reflux. Thirty children with a mean age of 72 days (21-252 days) were studied. The results showed that specificity of sonographic diagnosis was 87.5% and sensitivity was 100% (with P less than 0.001). Sonography also proved helpful in providing both functional and morphological data in addition to pH-metric results. This study therefore suggests that sonography is useful as the first approach in the diagnosis of vomiting babies as it is non-invasive and provides sufficient diagnostic accuracy.

Although cytomegalovirus infection is the most common infection transmitted via the placenta, there are no guidelines for routine screening to detect children congenitally infected with cytomegalovirus. From 1993 to 1997, maternal serum and cord vein blood of newborns was screened for HCMV-IgM (n = 21,183). Urine was examined for HCMV-excretion during the first postnatal week to prove HCMV infection in children who expressed HCMV-IgM in cord vein blood (n = 13) or who were born to mothers positive for HCMV-IgM in the serum (n = 234), or when both cord vein blood and maternal serum were positive for HCMV-IgM (n = 6). Congenital HCMV infection was detected in 17 newborns. To determine the incidence of congenital HCMV infection, only those mother/child pairs were selected in whom serum and cord vein blood were investigated (n = 5967 mother/child pairs). In this group 13 newborns were infected. The observed incidence for congenital HCMV infection is 0.21%. It is concluded that that this screening programme will detect those children at risk for congenital HCMV infection. These children have to be examined for virus excretion in the urine. Although the observed incidence is only 0.21%, congenital HCMV infection is a problem that can no longer be neglected because of its long-term sequelae.

The evaluation of reflux nephropathy (RNP) is a major task in the following up of children with vesicoureteral reflux (VUR). Adequate monitoring of RNP development depends on the frequent use of sonographical and scintigraphical examinations. In order to evaluate the accuracy of sonography in monitoring RNP 63 patients suffering from VUR (mean age: 8.8 years, range: newborn to 18 years, male:female = 19:44) were examined prospectively. We calculated renal size sonographically and compared our data to static and dynamic renographic findings. Our results showed a good correlation between relative DMSA uptake and sonographically estimated relative renal size (r = 0.95, P < 0.001), whereas not unexpectedly the correlation between relative kidney function and sonographically estimated renal size was poor (r = 0.83, P < 0.01). We therefore believe, that in monitoring children with VUR, sonography can offer accurate information on questions about renal size and renal parenchymal structure as well as pelvic distention. With very small kidneys as well as with kidneys showing severe dilatation and above all for evaluating renal function, scintigraphy proved to be the better method.