[Imaging of acute abdomen in childhood and adolescence]. / Bildgebung beim akuten Abdomen im Kindes- und Jugendalter.

Acute abdominal pain in childhood is a frequent reason for a medical consultation. The main diseases that lead to the clinical situation of acute abdomen show a significant age dependency. It is reasonable to group such ailments into three age categories: (1) the neonatal and infant period, (2) toddlerhood to kindergarten and (3) school age children. The task of the pediatric radiological examination is the differential diagnostic correlation of symptoms to the respective diseases. In children ultrasound is the appropriate method of choice.

[Comparative ultrasound visualization of clinically relevant structures for evaluating the infant hip joint utilizing trapezoidal vs. parallel transducers]. / Vergleichende Darstellung beurteilungsrelevanter Strukturen der kindlichen Hüfte mittels paralleler und trapezförmiger Ultraschallabbildung.

PURPOSE: Sonographic evaluation of the infant hip joint according to the method of Graf has proven to be an important pediatric investigative instrument. Our goal was to investigate quantitatively whether (and in what ways) the clinically relevant infant hip joint structures visualize differently when utilizing trapezoidal as opposed to linear transducers. Our approach was both theoretical via a mathematical model and practical with in-vivo measurements in neonates. MATERIALS AND METHODS: In a prospective study: 1. theoretical and computed analyses were performed for both linear and trapezoidal transducers regarding their respective accuracy for demonstrating the anatomic geometry of the infant hip, assuming not only correctly centered transducer positioning but also cases with off-centered displacement in the cranial or caudal direction; 2. both hip joints in 97 infants were examined by experienced investigators with comparison of the results for parallel vs. trapezoidal transducers. RESULTS: Theoretical mathematical error analysis reveals no intrinsic systemic deviations between trapezoidal vs. parallel transducers in US scanning of the infant hip and furthermore no inherent disadvantages in the trapezoidal technique. Even when off-center transducer alignments of 1.5 cm are employed in the mathematical models, there is no significant relative distortion of the required anatomic structures when comparing the characteristics of both transducers. The practical in-vivo data from our 97 neonates confirmed the theoretical considerations. CONCLUSION: No loss of accuracy or other negative factors are evident when trapezoidal transducers are used to visualize the infant hip joint in comparison with the customary parallel technique. There are no significantly measurable differences between the two approaches.

[Thoracic findings in pediatric patients with cystic fibrosis]. / Thorakale Veränderungen bei zystischer Fibrose im Kindesalter.

Cystic fibrosis is the most common autosomal recessive metabolic disease in Europe with an incidence of 1:2500. The severity of the lung disease is the most important factor of morbidity and mortality in CF-patients. Because of the better diagnostic and therapeutic modalities life expectancy has increased significantly. The underlying pathology is a defect of chromosome 7, which encodes the regulation of the fluid balance across the cell membrane which effects chloride as well as sodium. The exocrine glands produce a viscous mucus which obstructs the airways and promotes infections. The result is the destruction of lung parenchyma. In daily routine, chest x-ray is still the most important radiological tool, although computed tomography depicts changes in morphology earlier and more exactly. Recent research studies show that MRI has-because of its additional functional options-interesting aspects for the future.

Improved estimates of global ocean circulation, heat transport and mixing from hydrographic data.

Through its ability to transport large amounts of heat, fresh water and nutrients, the ocean is an essential regulator of climate. The pathways and mechanisms of this transport and its stability are critical issues in understanding the present state of climate and the possibilities of future changes. Recently, global high-quality hydrographic data have been gathered in the World Ocean Circulation Experiment (WOCE), to obtain an accurate picture of the present circulation. Here we combine the new data from high-resolution trans-oceanic sections and current meters with climatological wind fields, biogeochemical balances and improved a priori error estimates in an inverse model, to improve estimates of the global circulation and heat fluxes. Our solution resolves globally vertical mixing across surfaces of equal density, with coefficients in the range (3-12) x 10(-4) m2 s(-1). Net deep-water production rates amount to (15 +/- 12) x 10(6) m3 s(-1) in the North Atlantic Ocean and (21 +/- 6) x 10(6) m3 s(-1) in the Southern Ocean. Our estimates provide a new reference state for future climate studies with rigorous estimates of the uncertainties.

Abdominal aortic aneurysm. Detection of multilevel vascular pathology by time-resolved multiphase 3D gadolinium MR angiography: initial report.

OBJECTIVE: To evaluate multiphasic 3D gadolinium-enhanced magnetic resonance angiography (3D-Gd-MRA) for detection of vascular pathology at multiple levels of the aorta and iliac arteries. METHODS: In 18 patients with abdominal aortic aneurysm (n = 13), dissection (n = 3), or both (n = 2), multiphase 3D-Gd-MRA was performed acquiring five consecutive (6.8 seconds) 3D data sets in a single breath-hold. In each of the five time-resolved phases, vessel visibility of the abdominal aortic branches and iliac arteries was assessed. The extent of vessel involvement by the aneurysm or dissection seen on multiphase 3D-Gd-MRA was compared with standard imaging and surgical findings. Digital subtraction angiography was available for comparison in 4 cases, CT angiography in 10 cases. RESULTS: Due to the delayed filling of the aortic aneurysm, the proximal aortic branches and the aneurysm neck demonstrated an inversely related enhancement compared with the distal abdominal and iliac vessels (P < 0.001). Review of all five phases of multiphase 3D-Gd-MRA allowed optimal visualization of each vessel segment without any artifacts due to parenchymal or venous overlay. In dissections, review of three phases was required (P < 0.001) for diagnostic evaluation of the true and false lumens. Substantially more vessel involvement was detected on multiphase 3D-Gd-MRA; this was surgically confirmed in 10 of 11 cases and affected therapy management in 11 of 18 cases. CONCLUSIONS: Multiphase 3D-Gd-MRA is a convenient, robust, and safe technique for presurgical anatomic mapping of complex aortic aneurysms and dissections.

[Foreign body ingestion]. / Fremdkörperingestion.

Foreign body ingestion is not infrequent in infants and children. The diagnosis of radiopaque foreign body ingestion does not pose a major problem. It is crucial to take an X-ray from the pharynx to the level of the pylorus. If a foreign body that might get stuck at the ileocoecal valve is ingested, it is necessary to perform a radiograph of the whole abdomen. Foreign bodies that do not pass the cardia must be extracted endoscopically. In the case of foreign bodies with a smooth contour that have passed the pylorus, parents are advised to check the child's stool or collect it and bring it for X-raying. If after a week there is no definite evidence that the foreign body has been excreted a follow-up radiograph is carried out. If the foreign body is still in the stomach or duodenum, endoscopy is necessary. The detection of nonopaque foreign bodies can be facilitated by giving oral contrast medium, making the depiction of the foreign body as a filling defect possible. As a complication, perforation can occur, the diagnosis of which may entail the use of sonography, conventional radiography and, to a lesser extent, CT.

[Foreign body aspiration]. / Fremdkörperaspiration.

Aspiration of foreign bodies is a common cause of respiratory distress in children between the age of 6 months and 3 years. The diagnosis of radiopaque foreign bodies is easy when the whole respiratory tract is depicted. Nonopaque foreign bodies need a more differentiated diagnostic approach. The first step should be plain films in inspiration and expiration. The performance of additional chest radiographs, fluoroscopy and if need be CT or nuclear scans depends on the result of the plain films. The chest radiograph may reveal a variety of findings, the commonest of which is unilateral air trapping. Rarely, atelectasis, recurrent pneumonia at the same localisation and inspiratory obstruction are found. Combinations of the above-mentioned findings are possible. Moreover, the absence of positive radiological findings does not exclude the diagnosis of foreign body aspiration.

[CT-angiography as a non-invasive method for the evaluation of the patency of TIPSS (transjugular intrahepatic portasystemic shunt)]. / CT-Angiographie zur nicht-invasiven Kontrolle der Offenheit des TIPSS.

PURPOSE: To evaluate the feasibility of determining patency of the transjugular intrahepatic portosystemic shunt (TIPSS) by non-invasive CT angiography (CTA). MATERIALS AND METHODS: (1) Non-enhanced scanning of the shunt. (2) Bolus tracking by injecting 20 ml of non-ionic contrast material through a cubital vein access to determine the time to maximal shunt enhancement. (3) Contrast-enhanced spiral CT study applying a delay according to the time to peak of the shunt, 3 mm collimation, 5 mm table feed and 3 mm reconstruction interval. (4) 3D and multiplanar reconstructions. (5) Evaluation of the questions: intrahepatic shunt patent or not; evidence of intimal hyperplasia; evidence of stenosis and potential location. (6) Transjugular portography via the stent. (7) Comparison of angiographic findings and CT morphology. RESULTS: Eight patients had inconspicuous CTA. Four of them had a normal shunt at angiography, four had slight intimal hyperplasia. No intervention was necessary in these patients. CTA of three patients showed intimal hyperplasia (lumen reduction between 10% and 50%). The diagnosis was angiographically confirmed in all cases. Due to a high portosystemic gradient intervention was required in all. In five patients CTA and angiography showed a stenosis (reduction of shunt lumen > 50%). All required a revision including stent placement or PTA of the shunt tract. Four shunts were occluded; all occlusions were shown both in CTA and angiography. CONCLUSIONS: None of the shunts with normal findings at CTA required revision. All shunts conspicuous on CTA resulted in revision. In this study, CTA turned out to be an accurate, non-invasive method to evaluate the patency of TIPSS.

[Diagnostic imaging for therapy control of primary bone tumors]. / Bildgebende Diagnostik zur Therapiekontrolle primärer Knochentumoren.

Adjuvant chemotherapy has significantly improved the prognosis of patients with bone sarcomas. Preoperative diagnostic imaging of tumor response to such therapy has become a mainstay for the assessment of prognosis, planning of surgery and further treatment. During therapy, responding tumors show characteristic changes on conventional radiography, angiography, sonography, radionuclide studies, CT and MR. The usefulness and the limitations of each imaging modality in assessing response to therapy are reviewed. The diagnostic importance of specific changes such as tumor volume reduction, calcification and tumor vascularization is discussed.

[Radiologic diagnosis of bone metastases]. / Radiologische Diagnostik von Knochenmetastasen.

Metastases are the most common malignant tumors of the skeleton. Several imaging modalities can be engaged for the diagnosis of skeletal metastases. They may be combined, depending on the individual clinical setting. Plain films are used for evaluation of symptomatic regions of the skeleton. Sensitivity is low, but benign skeletal disorders causing clinical symptoms can usually be identified in plain films. Bone scintigraphy is employed for a survey of the entire skeleton with high sensitivity for the presence of metastases, but only poor specificity. Computed tomography (CT) and magnetic resonance imaging (MRI) are advanced diagnostic methods, essential particularly in the diagnosis of metastatic spinal disease. Using CT, additional percutaneous bone biopsies can be performed easily and safely. Of all imaging modalities, MRI has the highest sensitivity for skeletal metastases. Other advantages are the possibility of multidirectional slice positioning and excellent soft tissue contrast.

[Hydro-CT in detection and staging of pancreatic carcinoma]. / Hydro-CT in der Detektion und im Staging des Pankreaskarzinoms.

PURPOSE: To document our experience with spiral hydro-CT of the pancreas based on a combination of pharmacologic intestinal paralysis and water distension of the stomach and duodenum with specific reference to tumor detection rate, differentiation of malignant versus benign tumors and assessment of tumor resectability in a prospective study on 211 consecutive patients. MATERIAL AND METHODS: Between May 1994 und September 1997, 211 patients with suspect of pancreatic neoplasm from clinical, laboratory or other imaging data were examined. Our Hydro-CT techniques were based on intravenous injection of 40 mg N-butylscopolaminiumbromid (Buscopan) for intestinal paralysis, gastric and duodenal wall distension by oral administration of an average of 1.5 l warm tap water, 30 degrees RAO patient's positioning, individualized contrast injection technique using portal vein enhancement as reference and thin slice spiral CT (3 mm slice thickness, 6 mm table feed and 3 mm secondary reconstruction). Examined parameters were: (1) tumor detection rate, (2) differentiation of malignant versus benign disease, (3) differential diagnosis and (4) accuracy of assessment of resectability by identification of infiltration into adjacent organs and vessel structures relevant for resectability such as splenic, superior mesenteric, portal vein and celiac trunk, superior mesenteric, splenic and hepatic arteries. As gold standard for positive tumor detection and description surgery (of potentially resectable tumors) and microscopic diagnosis (of clearly unresectable tumors) were used and for negative tumor detection an event-free survival of six months, respectively. RESULTS: 96% of the examinations were well tolerated. In only 4% was on-site administration of a gastric tube required because of vomiting. In 2% of the patients a slight allergic reaction to the contrast medium was seen. The prevalence of a pancreatic neoplasm was 37.8%. In tumor detection Hydro-CT reached an overall accuracy of 94.8% with a sensitivity of 93.7% and a specificity of 95.2%. 52 patients underwent surgical exploration 34 of whom with tumorfree resection margins (RO resection) corresponding to a resection of 42.5%. In those assessment of resectability reached an overall accuracy of 94.6% with a sensitivity of 91.2% and specificity of 95.6%. CONCLUSION: The new technique of Hydro-CT based on the slice and spiral methodology including pharmacologic intestinal paralysis and water distension results in a high tumor detection rate and reliable assessment of resectability.

[Malignant lymphoma. Diagnosis and after-care in adults with special reference to cross-sectional imaging]. / Maligne Lymphome. Diagnostik und Nachsorge beim Erwachsenen unter besonderer Berücksichtigung der Schnittbildverfahren.

Radiological staging continues to remain the basis of a critical therapy of malignant lymphoma. As staging system, the Ann Arbor classification with some added modification is used. Up to now, CT is the imaging study of choice for staging and follow-up of cases of lymphoma. In future however, due to the advantages of the MRI, parts of the staging will be performed by MRI only. Imaging studies provide accurate measurement of extent of nodal disease. The detection of extra-nodal disease depends on the growth pattern and on the location. Focal lesions of sufficient size can be readily detected, diffuse infiltration is often missed. Computed tomography precisely reflects pathologic changes of lung involvement, but the findings are not specific. One weakness of the imaging studies is the low detection rate of splenic and hepatic involvement. Staging of gastrointestinal lymphoma has been improved by "hydro-CT" or "Hydro-MRI".

[Lymphoma in childhood]. / Lymphome im Kindesalter.

Manifestation of childhood Hodgkin's disease and Non-Hodgkin's lymphoma differ, especially in the latter, from those in adults. Extranodal involvement is seen even more frequently in childhood Non-Hodgkin's lymphomas than in adults. This article reviews the radiological findings in malignant lymphomas in children, explains the differences in the manifestation of Hodgkin's lymphomas, of different subtypes and of the malignant lymphomas in adults. The problems in diagnosis of organ manifestation and special problems of diagnostic imaging procedures in children are discussed.

[Malignant lymphoma in childhood. Ultrasound diagnosis]. / Maligne Lymphome im Kindesalter. Ultraschalldiagnostik.

The sonographic diagnosis of malignant lymphoma in childhood is described. Malignant lymphomas are sonographically relatively uniform: initial enlargement of the lymph nodes and organs involved and disturbance of normal echo texture by mainly hypoechoic lesions can be found. Generally, four sonographic patterns of infiltration are described: diffuse, small nodular, large nodular and bulky type. Secondary, tumor-related or inflammatory complications (e.g. dislocation or compression of vessels, thoracic inlet syndrome, venous thrombosis, ileus, urinary retention, abscess and effusion) can be sonographically evaluated. Response to therapy correlates with normalization of size and echo texture and recovery from tumor-related complications. Differential diagnosis with ultrasound is based on the topographic distribution and echo pattern of infiltration and, with certain restrictions, on the echogenicity of lesions and perfusion feasible with Doppler sonography. The primary diagnosis has to be established histologically.

A multicenter, uncontrolled clinical investigation of the contraceptive efficacy, cycle control, and safety of a new low dose oral contraceptive containing 20 micrograms ethinyl estradiol and 100 micrograms levonorgestrel over six treatment cycles.

The aim of the trial was to demonstrate the contraceptive efficacy of a new low dose oral contraceptive containing 20 micrograms ethinyl estradiol and 100 micrograms levonorgestrel and to observe cycle control and safety. Data from 805 treated women resulted in 4400 treatment cycles. One pregnancy occurred while on the trial medication as a result of method failure, resulting in a Pearl index of 0.29. Cycle control was good, and cycle length as well as duration and intensity of withdrawal bleeding were not significantly changed during the trial. Intermenstrual bleeding usually occurred as spotting and decreased considerably during the treatment phase. Spotting alone was reported in 12.4% of cycles, breakthrough bleeding alone in 4.5% of cycles, and breakthrough bleeding and spotting together in 1.4% of treatment cycles. The rate of absence of withdrawal bleeding declined throughout the trial to 2.4% in cycle 6. There were no serious adverse events related to treatment, and most adverse events were those commonly observed in clinical trials with oral contraceptives. Headache, breast tension, and nausea were reported by 17.3%, 11.0%, and 7.7% of the women, respectively. There were no clinically relevant changes in laboratory parameters, blood pressure, or weight. In this trial, the new low dose oral contraceptive containing 20 micrograms ethinyl estradiol and 100 micrograms levonorgestrel was shown to be effective, safe, and well tolerated. Cycle control was found to be good and there was a low incidence of adverse events.

PIP: The contraceptive efficacy, cycle control, and safety of a new low-dose oral contraceptive (OC) containing 20 mcg of ethinyl estradiol and 100 mcg of levonorgestrel were investigated in a multicenter clinical study involving 805 German women (average age, 25.6 years) and a total of 4400 treatment cycles. There was one case of method failure, yielding a Pearl index of 0.29. A regular withdrawal bleed occurred in 95.5% of all treatment cycles. Cycle length and the duration and intensity of withdrawal bleeding were not significantly altered by use of the low-dose OC. Spotting alone occurred in 12.4% of treatment cycles and breakthrough bleeding alone was reported in 4.5%; both symptoms occurred in 1.4% of cycles. Headache, breast tension, and nausea were reported by 17.3%, 11.0%, and 7.7% of women, respectively. Only 8.4% of women discontinued OC use due to adverse events. Finally, there were no clinically relevant changes in laboratory parameters, blood pressure, or body weight. Overall, these findings suggest that substantial reductions in the estrogen and progestogen doses of OCs do not compromise contraceptive efficacy or cycle control.

Recovery of interphase nuclei from extreme structural alterations in centrifuged fern protonemal cells.

Nuclear ability to recover morphologically and physiologically from tremendous elongation induced by centrifugation was investigated in single-celled protonemata of the fern Adiantum capillus-veneris. Basipetal centrifugation at a strength of ca. 2000 g for more than 1 h caused an extremely long (more than 500 microns), thread-like chromatin-containing extension of the nuclear envelope in the centrifugal direction. The nucleolus was either located inside a terminal widening of the extension, or it was detached from the thread and located outside the nucleus. Such enucleolation occurred in about half of the nuclei during 3 h of basipetal centrifugation. After centrifugation, the nuclei recovered morphologically by completely reducing the chromatin thread. One day after the end of centrifugation, all nuclei again contained a nucleolus, indicating that nucleolar regeneration had taken place in the interphase nucleus. Almost all basipetally centrifuged cells were still able to divide under white light conditions. A strong delay in the division time course may be attributed to recovery processes of the nuclear internal order. The remarkable ability of the Adiantum interphase nuclei to recover morphologically and physiologically is assumed to be due to processes which also drive the maintenance of the functional nuclear structure during interphase.

Investigation of the influence of two low-dose monophasic oral contraceptives containing 20 micrograms ethinylestradiol/75 micrograms gestodene and 30 micrograms ethinylestradiol/75 micrograms gestodene, on lipid metabolism in an open randomized trial.

An open comparison at a single center was performed in volunteers (n = 58) randomly allocated to two treatment groups, one receiving tablets containing 20 micrograms ethinylestradiol (EE) + 75 micrograms gestodene, and the other 30 micrograms EE + 75 micrograms gestodene. The study consisted of three treatment-free pre-cycles, followed by thirteen 28-day treatment cycles. Analysis of results revealed that there were no statistically significant differences between the two groups with regard to the plasma levels of HDL-cholesterol and its subfractions, LDL-cholesterol and apolipoproteins. There was, however, a trend toward a more favorable effect on HDL-cholesterol in the 20 micrograms EE group, where levels increased by 3% compared with the 30 micrograms EE group, where levels decreased by 9%. There was a statistically significant difference between the adjusted mean values of total triglycerides in the two groups in favor of the 20 micrograms EE group (+21%), compared with the 30 micrograms EE group (+64%) (p = 0.029). Two serious adverse events were reported (lymphadenopathy and vertigo), but neither were considered to be causally related to either study medication. The formulation containing 75 micrograms gestodene and 20 micrograms EE was shown to be a reliable and well tolerated oral contraceptive, with a favorable lipid profile.

Inhibition of ovulation by an oral contraceptive containing 100 micrograms levonorgestrel in combination with 20 micrograms ethinylestradiol.

Twenty-four healthy female volunteers with normal ovulatory cycles, aged between 20 and 34 years (27.5 +/- 4.3), were included in a single-center, non-comparative study to investigate the effect on inhibition of ovulation of an oral contraceptive containing 20 micrograms ethinylestradiol in combination with 100 micrograms levonorgestrel. At baseline, during three treatment cycles and post-treatment, ultrasonography was used to examine the ovaries, to measure follicular size, and to measure the thickness of the endometrium. Serum levels of LH, FSH, estradiol, progesterone, total testosterone, free testosterone, SHBG, and CBG were also measured. Compared with treatment cycle 1, an increase in residual ovarian activity (follicle grades 4-5) was observed in cycles 2 and 3. Mean levels of LH, FSH, 17 beta-estradiol and progesterone remained suppressed during treatment. No escape ovulation was observed during the treatment phase of the study and there were no pregnancies. Ovulation was noted to return rapidly in the posttreatment cycle. Subjective and objective tolerance of the present regimen was noted to be good. Results indicate that the monophasic oral contraceptive containing 100 micrograms levonorgestrel combined with 20 micrograms ethinylestradiol effectively inhibits ovulation, providing adequate suppression of ovarian activity.

[Spiral CT portography in preoperative diagnosis of liver metastases]. / Die Spiral-CT-Portographie in der präoperativen Diagnostik von Lebermetastasen.

Within a period of 12 months we preoperatively performed spiral CT portography (CT-AP) including individual determination of contrast injection kinetics, in 18 consecutive patients. The findings were compared with the microscopic findings in 15 resected specimens. A total of 51 perfusion defects were identified with CT-AP, 40 of which were finally diagnosed as metastases. A total of 36 hepatic lesions were identified at microscopy. 28 of which were metastases, all seen at CT-AP. 12 perfusion defects were misdiagnosed false positive as being of metastatic origin. Thus the sensitivity of CT-AP was 100%, the specificity 65% and the overall accuracy 78%. Therefore, CT-AP using the spiral CT technique is currently the most accurate method for preoperative staging of metastatic disease of the liver. Improvements of the scanning and contrast injection techniques will further improve the clinical value of this examination.