Evidence for Chiral Wobbler in Nuclei.

Three ΔI=1 bands with the πg_{9/2}⊗νg_{9/2} configuration have been identified in _{35}^{74}Br_{39}. Angular distribution, linear polarization, and lifetime measurements were performed to determine the multipolarity, type, mixing ratio, and absolute transition probability of the transitions. By comparing these experimental observations with the corresponding fingerprints and the quantum particle rotor model calculations, the second and third lowest bands are, respectively, suggested as the chiral partner and one-phonon wobbling excitation built on the yrast band. The evidence indicates the first chiral wobbler in nuclei.

Management of benign liver tumors.

Benign liver tumors in children are far less frequent than their malignant counterparts. Recently, there have been advances of diagnostic procedures and novel treatments with improved classification as a result. While malignant pediatric liver tumors have been comprehensively addressed by multicenter international tumor trials, benign tumors have more usually relied upon individualised workup and treatment. Due to the rarity and heterogeneity of these different entities, large studies are lacking. In this article the authors highlight the spectrum of benign liver tumors with special focus on specific clinical features, pathology, and treatment.

[Simultaneous whole-body PET-MRI in pediatric oncology : More than just reducing radiation?]. / Simultane Ganzkörper-PET-MRT in der pädiatrischen Onkologie : Mehr als nur Strahlenersparnis?

Diagnostic imaging plays an essential role in pediatric oncology with regard to diagnosis, therapy-planning, and the follow-up of solid tumors. The current imaging standard in pediatric oncology includes a variety of radiological and nuclear medicine imaging modalities depending on the specific tumor entity. The introduction of combined simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) has opened up new diagnostic options in pediatric oncology. This novel modality combines the excellent anatomical accuracy of MRI with the metabolic information of PET. In initial clinical studies, the technical feasibility and possible diagnostic advantages of combined PET-MRI have been in comparison with alternative imaging techniques. It was shown that a reduction in radiation exposure of up to 70 % is achievable compared with PET-CT. Furthermore, it has been shown that the number of imaging studies necessary can be markedly reduced using combined PET-MRI. Owing to its limited availability, combined PET-MRI is currently not used as a routine procedure. However, this new modality has the potential to become the imaging reference standard in pediatric oncology in the future. This review article summarizes the central aspects of pediatric oncological PET-MRI based on existing literature. Typical pediatric oncological PET-MRI cases are also presented.

Evidence for Octupole Correlations in Multiple Chiral Doublet Bands.

Two pairs of positive-and negative-parity doublet bands together with eight strong electric dipole transitions linking their yrast positive- and negative-parity bands have been identified in ^{78}Br. They are interpreted as multiple chiral doublet bands with octupole correlations, which is supported by the microscopic multidimensionally-constrained covariant density functional theory and triaxial particle rotor model calculations. This observation reports the first example of chiral geometry in octupole soft nuclei.

Dynamic MR urography in children with uropathic disease with a combined 2D and 3D acquisition protocol--comparison with MAG3 scintigraphy.

OBJECTIVE: The aim of this study was to evaluate combined two-dimensional (2D) and three-dimensional (3D) dynamic MR urography with respiratory compensation in children with anomalies of the genitourinary tract, allowing for computation of split renal function and assessment of urinary tract obstruction. METHODS: Dynamic MR urography was performed in 53 children (3 months-16 years of age) with anomalies of the urinary tract. A protocol for dynamic MR urography and nephrography was implemented at 1.5 T using a navigator-triggered 2D TurboFLASH sequence. Split renal function and contrast-medium excretion were assessed after the bolus injection of 0.05 mmol kg(-1) body weight of gadolinium dimeglumine. In the excretory phase, a 3D gradient-echo data set with high spatial resolution was acquired. In all patients, mercaptoacetyltriglycine (MAG3) scintigraphy was obtained as a reference standard. RESULTS: In all children, dynamic MR nephrography and urography could be performed with excellent compensation of breathing artefacts providing region of interest analysis in nearly identical kidney positions. The assessment of contrast-medium excretion into the ureter allowed for discrimination of functional from non-functional stenosis. Split renal function assessed by MRI showed an excellent agreement with the MAG3 reference standard with a correlation coefficient r = 0.95. Additionally recorded 3D data sets offered good depiction of anatomical anomalies in all patients. CONCLUSION: The proposed protocol provides a robust technique for assessment of ureteral obstruction and split renal function with compensation of breathing artefacts, short post-processing time and excellent 3D spatial resolution. ADVANCES IN KNOWLEDGE: The combined protocol of 2D and 3D MR urography is an efficient technique for assessment of renal morphology and function.

High-pitch computed tomography of the lung in pediatric patients: an intraindividual comparison of image quality and radiation dose to conventional 64-MDCT.

PURPOSE: The aim of this study was to investigate frequencies of typical artifacts in low-dose pediatric lung examinations using high-pitch computed tomography (HPCT) compared to MDCT, and to estimate the effective radiation dose (Eeff). MATERIALS AND METHODS: Institutional review board approval for this retrospective study was obtained. 35 patients (17 boys, 18 girls; mean age 112 ±â€Š69 months) were included and underwent MDCT and follow-up scan by HPCT or vice versa (mean follow-up time 87 days), using the same tube voltage and current. The total artifact score (0 - 8) was defined as the sum of artifacts arising from movement, breathing or pulsation of the heart or pulmonary vessels (0 - no; 1 - moderate; 2 - severe artifacts). Eeff was estimated according to the European Guidelines on Quality Criteria for Multislice Computed Tomography. The Mann-Whitney U test was used to analyze differences between the patient groups. The Spearman's rank correlation coefficient was used for correlation of ordinal variables. RESULTS: The scan time was significantly lower for HPCT compared to MDCT (0.72 ±â€Š0.13 s vs. 3.65 ±â€Š0.81s; p < 0.0001). In 28 of 35 (80 %) HPCT examinations no artifacts were visible, whereas in MDCT artifacts occurred in all examinations. The frequency of pulsation artifacts and breathing artifacts was higher in MDCT compared to HPCT (100 % vs. 17 % and 31 % vs. 6 %). The total artifact score significantly correlated with the patient's age in MDCT (r = - 0.42; p = 0.01), but not in HPCT (r = - 0.32; p = 0.07). The estimated Eeff was significantly lower in HPCT than in MDCT (1.29 ±â€Š0.31 vs. 1.47 ±â€Š0.37 mSv; p < 0.0001). CONCLUSION: Our study indicates that the use of HPCT has advantages for pediatric lung imaging with a reduction of breathing and pulsation artifacts. Moreover, the estimated Eeff was lower. In addition, examinations can be performed without sedation or breath-hold without losing image quality. KEY POINTS: • Fewer artifacts in pediatric lung imaging with HPCT• Reduced Eeff in HPCT• HPCT without sedation or breath-hold without loss of image quality.

Nephron sparing surgery for synchronous bilateral nephroblastoma involving the renal hilus.

PURPOSE: Bilateral nephroblastoma involving the renal hilus represents a significant surgical challenge. Different operative strategies have been proposed for this condition. We analyzed the outcome of simultaneous bilateral partial nephrectomy for complex stage V nephroblastoma. MATERIALS AND METHODS: We retrospectively analyzed patients with bilateral nephroblastoma involving the renal hilus operated on at our institution between 2002 and 2008. We assessed patient data and surgical and oncologic outcomes. RESULTS: We analyzed data from 5 patients with a median age of 27 months at surgery (range 13 to 58). Two children had additional pulmonary metastases. Patients were treated according to the International Society of Pediatric Oncology 2001/German Society of Pediatric Oncology and Hematology protocol. All children underwent synchronous bilateral nephron sparing surgery (longitudinal partial nephrectomy or enucleation) of the central tumors. Median operating time was 182 minutes (range 129 to 291), with vascular exclusion performed in 4 patients (7 to 25 minutes). Complications consisted of urinary leakage in 2 cases. Postoperative renal function was unimpaired in 4 patients and 1 patient had Wilms tumor/aniridia/genitourinary malformations/retardation syndrome with glomerulopathy. One patient with pulmonary metastases and blastemal histology had multiple pulmonary relapses and died due to pulmonary progressive disease. Four patients are alive without evidence of disease at a median followup of 45 months (range 44 to 73). CONCLUSIONS: Surgery for central stage V nephroblastoma is possible with good functional and oncologic outcomes. The single stage approach is safe, provided that operating and treating physicians have sufficient expertise with such conditions. The ultimate goal is to avoid tumor nephrectomy.

Two-particle separation energy trends in the superdeformed well.

A measurement of the energy and spin of superdeformed states in 190Hg, obtained through the observation of transitions directly linking superdeformed and normal states, expands the number of isotopes in which binding energies at superdeformation are known. Comparison with neighboring nuclei shows that two-proton separation energies are higher in the superdeformed state than in the normal state, despite the lower Coulomb barrier and lower total binding energy. This unexpected result provides a critical test for nuclear models.

Nonzero quadrupole moments of candidate tetrahedral bands.

Negative-parity bands in the vicinity of 156Gd and 160Yb have been suggested as candidates for the rotation of tetrahedral nuclei. We report the observation of the odd and even-spin members of the lowest energy negative-parity bands in 160Yb and 154Gd. The properties of these bands are similar to the proposed tetrahedral band of 156Gd and its even-spin partner. Band-mixing calculations are performed and absolute and relative quadrupole moments deduced for 160Yb and 154Gd. The values are inconsistent with zero, as required for tetrahedral shape, and the bands are interpreted as octupole vibrational bands. The failure to observe the in-band E2 transitions of the bands at low spins can be understood using the measured B(E1) and B(E2) values.

Prevalence of vertebral alterations and the effects of calcium and vitamin D supplementation on calcium metabolism and bone mineral density after gastrectomy.

BACKGROUND: Bone disease is common after gastrectomy, resulting in decreased bone mass and an increased risk of fracture. No proven therapy is currently available. METHODS: Serum markers of calcium metabolism in 98 patients after partial or total gastrectomy were compared with those in 30 age- and sex-matched healthy controls. Patients with disorders of calcium metabolism were investigated by conventional radiography and single-energy computed tomography of the spine. Forty patients participated in a 1-year follow-up study to investigate the effects of vitamin D and calcium supplementation on calcium metabolism and bone mineral density. RESULTS: Altered serum markers of calcium and phosphate metabolism were observed in 77 (79 per cent) of 98 patients. Sixty (79 per cent) of these had vertebral alterations. Vertebral fractures were detected in 22 patients, grade I vertebral deformities in 50 patients, grade II deformities in 22 patients and osteopenia (Z-score less than - 1) in 30 patients. Calcium and vitamin D supplementation resulted in an increase in 25-hydroxy-vitamin D (P < 0.001), 1,25-dihydroxy-vitamin D (P = 0.048) and osteocalcin (P = 0.045), whereas levels of parathyroid hormone were decreased (P = 0.007). Bone mineral density did not change over time. CONCLUSION: Disturbances of calcium and bone metabolism are common after gastrectomy. Calcium and vitamin D supplementation normalized levels of markers of calcium metabolism and might have prevented age-related bone mass loss, although it did not increase bone mineral density after 1 year.

[Detection of pulmonary nodules with breath-hold magnetic resonance imaging in comparison with computed tomography]. / Detektion von Lungenrundherden mit der Magnetresonanztomographie in Atemanhaltetechnik im Vergleich zur Spiral-Computertomographie.

PURPOSE: Evaluation of sensitivity and false positive findings of two fast MRI sequences for the detection of pulmonary nodules in comparison with spiral CT by two independent observers. MATERIALS AND METHODS: All 30 enrolled patients had a spiral CT or MSCT as base line study. MRI was performed with a 1.5 T MR scanner (Sonata, Siemens) using a transverse 3D gradient echo sequence (3D-GRE: TR/TE/flip = 2.9 ms/1.1 ms/5 degrees ) and a half-Fourier single-shot fast spin-echo sequence (HASTE: TR/TE/flip = 800/25/150 degrees ) acquired in three planes. A separate analysis for both sequences was carried out prospectively by two independent readers (A and B) with different experience regarding pulmonary MRI. Additionally, a retrospective reading with knowledge of the CT scans was done. Results were calculated for all lesions and for lesions larger than 4 mm. RESULTS: The sensitivities were 73 %, 70 % and 84 % for the 3D-GRE sequence (reader A, reader B, retrospective reading) and 65 %, 68 % and 81 % for the HASTE sequence. For lesions larger than 4 mm, the sensitivities were 93 %, 89 %, 96 % for the 3D-GRE sequence and 85 %, 85 %, 96 % for the HASTE sequence. The rate of false positive findings depended on the reader's experience, but was generally lower for the 3D-GRE sequence with 2 and 16 (reader A and B) false positive nodules compared to 4 and 40 false positive findings for the HASTE sequence. The 3D-GRE sequence was more accurate for both readers (reader A: p = 0.08, reader B: p = 0.00003). CONCLUSION: The sensitivity of MRI for the detection of lung nodules was only acceptable for lesions larger than 4 mm. The 3D-GRE sequence is superior to the HASTE sequence due to the reduced amount of false positive findings with comparable sensitivity.

[Oncologic screening with whole-body MRI: possibilities and limitations]. / Onkologische Früherkennung mit der Ganzkörper-MRT: Möglichkeiten und Grenzen.

In the last decade the interest in radiological screening examination increased among informed laymen enormously. Independent from the evidence of whole-body examinations for cancer prevention the discussion about screening must again be considered again due to the newest technical developments, since MRI of the whole-body with high spatial resolution is feasible now within one single examination. The newest system permits simultaneous connection of up to 76 coil elements and signal reception from 32 independent receiving channels. Whole-body MRI including magnetic resonance colonography (MRC) is feasible within 60 min. In this review potential investigation protocols will be presented. Potentials, challenges and limitations of whole-body MRI in the prevention of the malignancies most frequently leading to death are discussed on the basis own experiences examples and the literature.

[Imaging diagnosis of solitary pulmonary nodules on an open low-field MRI system--comparison of two MR sequences with spiral CT]. / Bildgebende Diagnostik solitärer Lungenrundherde am offenen Niederfeld-MRT--Ein Vergleich zweier MR-Sequenzen mit der Spiral-CT.

OBJECTIVE: To evaluate and compare two fast gradient-echo sequences (GRE) concerning the visualization of solitary pulmonary nodules with an open low-field MRI system in comparison to computed tomography. MATERIALS AND METHODS: Fourteen patients with solitary pulmonary nodules detected by spiral CT ranging in size from 6 mm to 42 mm (mean 20 mm) underwent MRI on an open 0.2 T scanner using a spoiled 2D GRE (2D FLASH; TR/ TE/Flip = 100 ms/7.5 ms/30 degrees ) and a totally refocused 2D steady-state GRE (True-FISP; TR/TE/FA = 7.3 ms/3.5 ms/80 degrees ). The image quality concerning artifacts (by flow, breathing and susceptibility) and the morphologic characteristics of the nodules were scored and compared with CT by two independent radiologists. The diameters of the nodules measured by MRI were compared with CT measurements. The sequences were also evaluated with regard to the signal-to-noise ratio (SNR) of the lesion. RESULTS: All lesions were detected with the 2D FLASH sequence. True-FISP failed to find a granuloma with a size of 6 mm. The 2D FLASH was rated significantly superior to true FISP concerning image quality artifacts by susceptibility as well as concerning to CT the presentation of nodule characteristics. In MR images, the size of lesions was significantly smaller than in CT images for both sequences: for 2D FLASH the mean difference was 0.9 mm and for true FISP 2.6 mm. The SNR of the nodules was significantly higher for the 2D FLASH than for the true FISP. CONCLUSION: In low field MRI, the 2D FLASH sequence is superior to the 2D true FISP sequence in imaging of pulmonary nodules. With the 2D FLASH sequence nodules of 6 mm or larger in size can be visualized.

[CT-colonography: current status and future directions in consideration of the technical evolution]. / Technische Neuerungen in der CT-Kolonographie: gegenwärtiger Stand und zukünftige Entwicklung.

Computertomography and with it CT-colonography evolves technically and also possibilities of data processing proceed rapidly. The current status of CTC can be summarized as follows:The method represents a true alternative to barium enema if technical conditions are given.CTC can be performed with excellent results immediately following an incomplete colonoscopy. In pretherapeutic diagnosis of colorectal carcinoma, CTC can be combined with a staging CT of the abdomen. The recent technical advances with new 16 row technology in image quality and data acquisition - mainly concerning the spatial and temporal resolution - are very promising. Developments in postprocessing of CT data can also contribute to a higher efficiency of labor. Alternative preparation schemata can lead to a more comfortable bowel cleansing and stool labeling can even avoid this procedure, resulting both in an even improved compliance. Radiation exposure in low dose technique is comparable to a double contrast barium enema and can be still reduced by optimisation of scanning parameters.The aim of the following article is (1 to give an overview of the current status of patient preparation, image acquisition and data processing; (2) to review recent clinical trials and experimental studies and to show future directions of CTC with regard to the clinical development.

[Hybrid 3-D rendering of the thorax and surface-based virtual bronchoscopy in surgical and interventional therapy control]. / Hybride 3D-Visualisierung des Thorax und oberflächenbasierte virtuelle Bronchoskopie in der operativen und interventionellen Therapiekontrolle.

PURPOSE: The aim of this study was to demonstrate the possibilities of a hybrid rendering method, the combination of a color-coded surface and volume rendering method, with the feasibility of performing surface-based virtual endoscopy with different representation models in the operative and interventional therapy control of the chest. MATERIAL AND METHOD: In 6 consecutive patients with partial lung resection (n = 2) and lung transplantation (n = 4) a thin-section spiral computed tomography of the chest was performed. The tracheobronchial system and the introduced metallic stents were visualized using a color-coded surface rendering method. The remaining thoracic structures were visualized using a volume rendering method. For virtual bronchoscopy, the tracheobronchial system was visualized using a triangle surface model, a shaded-surface model and a transparent shaded-surface model. RESULTS: The hybrid 3D visualization uses the advantages of both the color-coded surface and volume rendering methods and facilitates a clear representation of the tracheobronchial system and the complex topographical relationship of morphological and pathological changes without loss of diagnostic information. Performing virtual bronchoscopy with the transparent shaded-surface model facilitates a reasonable to optimal, simultaneous visualization and assessment of the surface structure of the tracheobronchial system and the surrounding mediastinal structures and lesions. CONCLUSIONS: Hybrid rendering relieve the morphological assessment of anatomical and pathological changes without the need for time-consuming detailed analysis and presentation of source images. Performing virtual bronchoscopy with a transparent shaded-surface model offers a promising alternative to flexible fiberoptic bronchoscopy.

Linear polarization measurement of interband transitions in superdeformed 190hg: model-independent evidence for octupole vibrational structures.

The linear polarization of gamma rays between excited and yrast superdeformed (SD) states in 190Hg was measured using the four-element CLOVER detectors of the EUROBALL IV gamma-ray spectrometer. This measurement shows in a model-independent way that the interband transitions which compete with the highly collective in-band quadrupole transitions are largely enhanced electric dipoles. Not only do these results represent the first measurement of the multipolarity of transitions between different SD states, but they also provide strong evidence for the interpretation of the structures in the SD minimum of the A approximately 190 region in terms of octupole excitations.

Functional results after laparoscopic rectopexy for rectal prolapse.

We investigated the functional results after laparoscopic rectopexy for rectal prolapse in 29 patients at least 12 months postoperatively. Twenty patients were evaluated completely pre- and postoperatively (median 22 months postoperatively, range 12 to 54 months). Six patients were interviewed by telephone, two patients were lost to follow-up, and one patient died of causes unrelated to rectal prolapse. Patients underwent a proctologic examination, anoscopy, rigid sigmoidoscopy, fluoroscopic defecography, and anorectal manometry pre- and postoperatively, and an additional standardized interview postoperatively. Anorectal manometry showed a significant increase in maximum anal resting and squeeze pressures postoperatively (resting pressure 72 +/- 8 vs. 95 +/- 13 mm Hg, pre- vs. postoperatively; P = 0.046; squeeze pressure 105 +/- 17 vs. 142 +/- 19 mm Hg, pre- vs. postoperatively; P = 0.035), and continence improved postoperatively (Wexner incontinence score 6.0 +/- 1.0 vs. 3.9 +/- 0.8 pre- vs. postoperatively, P = 0.02). Twenty (77%) of 26 patients were satisfied with the operative result, but functional morbidity was observed in four patients, with two patients complaining of severe evacuation problems. Rectal prolapse recurred in one patient 42 months postoperatively (recurrence rate 1 [3.8%] of 26 patients). Functional results were very similar to those obtained after open rectopexy, with symptoms of prolapse and incontinence improved in the great majority of patients.

Pioneer leaders in plant pathology: ralph m. Caldwell.

Ralph Caldwell was a dynamic, innovative plant pathologist and plant breeder. His contributions to small grain cereal production in the Eastern United States were at the top of his field, and his achievements brought respect and honor to the Purdue University/US Department of Agriculture small grain research and breeding program, which he led. His approach to scientific problems was incisive. Dr. Caldwell was practically oriented, never losing sight of the societal benefits of his work. Nevertheless, he was a strong participant in and supporter of more basic research-believing that it was essential but not the total answer. One of his guidelines was that the applied program breeding for disease resistance-was central and required a team effort. It inevitably would run into problems that were not easily addressed in the ongoing team effort. These problems, in turn, became the objects of research studies, which were individually approached on second tracks by members of the "team." Research results were subsequently funneled back, as solutions for the specific problems, into the broadly based plant improvement program.