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This corrects the article DOI: 10.1103/PhysRevLett.120.166401.

Strongly correlated materials exhibit intriguing properties caused by intertwined microscopic interactions that are hard to disentangle in equilibrium. Employing nonequilibrium time-resolved photoemission spectroscopy on the quasi-two-dimensional transition-metal dichalcogenide 1T-TaS_{2}, we identify a spectroscopic signature of doubly occupied sites (doublons) that reflects fundamental Mott physics. Doublon-hole recombination is estimated to occur on timescales of electronic hopping ℏ/J≈14 fs. Despite strong electron-phonon coupling, the dynamics can be explained by purely electronic effects captured by the single-band Hubbard model under the assumption of weak hole doping, in agreement with our static sample characterization. This sensitive interplay of static doping and vicinity to the metal-insulator transition suggests a way to modify doublon relaxation on the few-femtosecond timescale.

Standardized methods and instruments of medical documentation are prerequisites for quality assurance in medicine. Support for quality assurance measures at present can be attained by the programme systems ID DIACOS (encoding of diagnoses into ICD-9 and procedures into ICPM-GE) for daily clinical routine documentation. Administrative statistics, e.g. the L1-statistics of diagnoses according to section 16 Federal Statutory Instrument on Hospital Care Rates (BPflV) can be compiled without waste by aggregation. Supplementations of the programme system are planned caused by the introduction of new forms of Hospital reimbursement with changed classification patterns. An increasing need for computer-aided encoding will also result by the implementation of new classifications, e.g. ICD-10 and by the requirements concerning a scientific basic documentation (Selbmann, 1990; Mau, 1990) based partly on nomenclatures. The connection of the programme systems ID DIACOS and SNOMED (empirical and morphological analysis of medical texts) is possible and will be carried out (Hultsch, Diekmann, Ruhl, 1990).

Introduction Chronic allograft dysfunction (CAD) is the main cause of late transplant failure. Although several etiologies have been postulated, toxicity for calcineurin inhibitors (CNIs) is one of the most important causes of CAD, characterized by arteriolar hyalinosis, luminal narrowing, increased glomerulosclerosis, and tubulointerstitial damage. It’s known that in transplant patients with CAD, fibrogenic mediators such as transforming growth factor beta (TGF-β) are increased. Sirolimus is an immunosuppressive agent with a distinct mechanism of action compared with CNI. Aim This study assessed variations in levels of fibrogenic mediators among CAD patients treated with CNIs, before and after conversion to sirolimus. Patients and methods We studied twelve renal transplant patients with CAD on CNI treatment. TGF-β in plasma and urine, endothelin-1, and vascular endothelial growth factor (VEGF) were studied before and 8 months after conversion to sirolimus treatment. Results TGF-β urine levels decreased from 24.7 ± 11.2 to 12.8 ± 5.1 ng/24 h ( P = .049). In plasma, a similar decrease trend was observed (22.2 ± 32 to 10.3 ± 3 ng/mL), although it was not significant ( P = .079). Endothelin-1 showed a decrease (8.1 ± 3 to 5.2 ± 1.1 pmol/L; P = .1) and VEGF in plasma increased from 34.3 ± 37 to 92.2 ± 86 pg/mL ( P = .051). Conclusions Patients undergoing conversion from CNI to sirolimus treatment for CAD presented a significant decrease in TGF-β urine levels, representing a decreased mediator of the CAD fibrogenic process.

Does the easier microcalcification detection (EMD) method enable sonographic visualization of microcalcifications in breast core biopsy specimens compared with mammography?In a prospective randomized study, 105 core biopsy specimens obtained with stereotactic guidance were examined by mammography and ultrasound. EMD is integrated in a high-end ultrasound system and uses three level settings (0 - 2 blue, 3 - 5 violet, and 6 - 8 black-and-white; 14 MHz). Detection of microcalcifications per core specimen was determined for ultrasound and mammography. EMD image quality was rated on a scale of 1 - 9. ANOVA and Sidak post-hoc testing, Pearson regression analysis (r), and Spearman rank correlation (rho) were performed. The intraclass correlation coefficient (ICC) was calculated, and an ROC analysis was conducted.The blue color map 1 was assigned the highest mean score of 1.5 ± 0.7 (p0.05 compared with black-and-white and violet). There was good correlation between the two modalities (r= 0.708 and rho= 0.694) with detection of 3.5 ± 3.1 microcalcifications per specimen by ultrasound versus 4.3 ± 4.8 by mammography (p0.05). The ICC of 0.773 indicates little disagreement between the two modalities. ROC analysis showed mammography to be superior to ultrasound compared with histological detection of microcalcifications (AUC= 0.837 vs. AUC= 0.728).Sonographic detection of microcalcifications in stereotactic biopsy specimens using the EMD method correlates well with digital mammography. Mammography is slightly superior.

BACKGROUND AND PURPOSE: Recently introduced 320-detector row CT enables whole brain perfusion imaging compared to a limited scanning area in 64-detector row CT. Our aim was to evaluate patient radiation exposure in comprehensive stroke imaging by using multidetector row CT consisting of standard CT of the head, CTA of cerebral and cervical vessels, and CTP. MATERIAL AND METHODS: Organ doses were measured by using LiF-TLDs located at several organ sites in an Alderson-Rando phantom. Effective doses were derived from these measurements. Stroke protocols including noncontrast head CT, CTA of cerebral and cervical vessels, and CTP were performed on 320- and 64-detector row scanners. RESULTS: Measured effective doses for the different scanning protocols ranged between 1.61 and 4.56 mSv, resulting in an effective dose for complete stroke imaging of 7.52/7.54 mSv (m/f) for 64-detector row CT and 10.56/10.6 mSv (m/f) for 320-detector row CT. The highest organ doses within the area of the primary beam were measured in the skin (92 mGy) and cerebral hemispheres (69.91 mGy). Use of an eye-protection device resulted in a 54% decrease of the lens dose measured for the combo protocol for whole-brain perfusion with the 320-detector row CT scanner. CONCLUSIONS: Phantom measurements indicate that comprehensive stroke imaging with multidetector row CT may result in effective radiation doses from 7.52 mSv (64-detector row CT) to 10.6 mSv (320-detector row CT). The technique of 320-detector row CT offers additional information on the time course of vascular enhancement and whole-brain perfusion. Physicians should weigh the potential of the new technique against the higher radiation dose that is needed. Critical doses that would cause organ damage were not reached.

Zielsetzung: Slot-Scan-Mammografie mit sogenanntem „phontonzahlenden Detektorsystem“ erlauben Kontrastmittel mit Dual-energy-Technik ohne Bewegungsartefakte zu visualisieren, indem bei nur einer Aufnahme im Detektor Hoch- und Niedrigenergetische Photonen separiert werden. Ziel dieser Studie war es aufzuzeigen, ob dieses Prinzip in klinisch relevanten Bereichen der Mammadiagnostik funktionieren kann. Material und Methoden: In einem Plexiglasphantom wurden Tumore mit Grosen zwischen 2,5 bis 10mm simuliert. Mithilfe unterschiedlicher Jodkonzentrationen (Kontrastmittel Ultravist 370, BayerSchering) wurde Tumorenhancement zwischen 0 und 8mg/ml simuliert. Das Phantom wurde mit einem System untersucht, welches im Rahmen des EU-Highrex-Projektes umgerustet wurde (Sectra Mamea, Stockholm, Schweden). Die fur die Aufnahmen verwendete berechnete mittlere Parenchymdosis betrug 0,6 mGy. Eine logarithmische, gewichtete Subtraktion wurde durchgefuhrt und die resultierenden Aufnahmen von drei Radiologen bewertet. Zusatzlich wurde das Kontrast-zu-Rauschverhaltnis (CNR) der unterschiedlichen Losungen bei den verschiedenen simulierten Tumordicken berechnet. Ergebnisse: Die minimal notwendige Jodkonzentration fur die Visualisierung von 10mm dicken Tumoren betrug 1mg/ml, 4mg/ml wurden fur einen 2,5mm dicken Tumor benotigt. CNR fur 8mg/ml Jod in 2,5/5/10mm dicken Tumoren im Vergleich zu Wasser wurde mit 0.697/1.393/2.935 berechnet, bei 4mg/ml Jod mit 0.343/0.507/1.287 und CNR bei 1mg/ml Jod betrug 0.084/0.214/0.485. Schlussfolgerung: Da aus Voruntersuchungen bekannt ist, dass Mammatumore protokollabhangig ca. 3–4mg/ml Jod anreichern, kann geschlussfolgert werden, dass unter optimalen Bedingungen mit der hier verwendeten Technik Tumoren bis zu einer minimalen Grose von 2,5mm visualisiert werden konnten. Das Kontrast-zu-Rausch-Verhaltnis ist fur den diagnostischen Bereich akzeptabel und fruheren Untersuchungen mit flat-panel-Detektoren mindestens ebenburtig. Diese Phantomuntersuchungen rechtfertigen Untersuchungen an Patientinnen.

The overriding goal of an organized mammography screening program is to offer high level medical care to everyone at a justifiable cost. The following overview will demonstrate how both aspects of screening, quality and cost efficiency, are supported by a fully digital workflow. Digital mammography systems allow for a constant high image quality and repeat examinations due to overexposure or underexposure can be avoided. Dedicated mammography screening workstations with integration of image viewing and reporting enable efficient softcopy reading. Many aspects of the screening workflow, such as double reading, archiving and retrieval of stored films, as well as information exchange between members of the certified team of the screening unit and other physicians involved in the further treatment, are made significantly easier by the presence of image data in digital form.

Available data suggest that early detection of breast cancer by mammography screening can reduce mortality by about 25%. Intensified monitoring of women with a family history of breast cancer and regular general screening have recently been introduced in Germany. The screening program is expected to be fully established by 2008. Following its successful introduction (participation rates between 65 and 80%), the German screening program will be conducted and evaluated in accordance with the European guidelines. At least in the screening trials that were conducted prior to the now established screening program the quality criteria were more than fulfilled (e.g. cancer detection rate in Bremen 8.7, Wiesbaden 9.4, Weser-Ems region 8.3/1000). Additional parameters that can be taken into account for quality assurance are the overdiagnosis bias, lead time bias, length bias and selection bias. Moreover, there are some factors that are specific to the German program compared with the breast cancer screening programs already established in other countries. One of these is the intensified screening program for high-risk women (ca. 5% of all carcinomas) and as a result fewer women with an increased genetic risk of breast cancer will be represented in the general screening program. The German screening program involves only a few university centers and hospital-based physicians, which may have adverse effects on research and development as well as mammography training in the future. Therefore, the screening program should also provide for the investigation of new techniques or emerging techniques (e.g. CAD systems in screening mammography) in the future.

To evaluate the role of preoperative MRI of the breast in invasive lobular carcinoma (ILC) compared to invasive ductal carcinoma (IDC).For one year, all patients transferred by the hospital's gynecologic outpatient service for suspicious findings in routine mammography and/or ultrasound (conventional modalities = CM) underwent preoperative MRI of the breast. Retrospective analysis of the histologic findings identified 17 patients with ILC. These were compared with 30 proven IDC patients, chosen by random. The MRI findings of these 2 patient groups were compared with regard to the detection of additional lesions. The average number of additional lesions detected by MRI was compared for significant differences between both groups using the T-test for paired samples.In the 17 patients with ILC, conventional modalities (CM) identified 21malignant lesions whereas MRI detected a total of 30 lesions. At least one additional lesion was detected by MRI in 7 of the 17 patients with ILC. In the 30 patients with IDC, on the other hand, MRI detected an additional lesion in three instances only. In one patient of the ILC group, MRI identified an additional lesion in the contralateral breast that had escaped detection by CM. No additional contralateral lesion was detected by MRI in any of the IDC patients. Benefit of MRI in ILC-Group: The mean numbers of detected malignant lesions differed significantly between diagnosis by MRI and CM in the ILC group (1.77 carcinomas per patient with MRI versus 1.24 with conventional modalities, T-test, p = 0.0078). Benefit of MRI in IDC-Group: although it was possible to find 1.27 carcinomas vs. 1.17 carcinomas per patient in the IDC-Group, this benefit was not statistical significant (T-test, p = 0.0831).Preoperative MRI detects multiple additional lesions compared to the ones already known by CM. The higher incidence of multiple lesions in ILC compared to IDC and the difficult diagnosis of ILC in CM might be the reason for the fact that preoperative MRI is particularly useful in patients with ILC.

To evaluate the visualization of microcalcifications on mammographies obtained by full-field digital mammography (FFDM) in comparison to conventional film-screen mammography (FSM).Forty-seven digital and film-screen mammographies depicting histologically proven lesions (27 benign, 20 malignant) were assessed by 4 readers. The images obtained with the different systems were comparable in terms of positioning. Maximum time interval between film-screen mammography and digital mammography was three months. Using a questionnaire, the readers evaluated the number of microcalcifications and their subjective conspicuity for FFDM (Senographe 2000D, GE Medical Systems, Milwaukee, USA) and FSM. A 7-point scale based on the BIRADS classification was used to characterize the calcifications by means of ROC analysis.No statistically significant differences were seen between the two types of mammography among the readers in assessing the number of microcalcifications. The subjective conspicuity of microcalcifications was found to be significantly better for digital mammographies. The diagnosis assigned by the readers did not show significant differences between the two systems.Although the subjective conspicuity of microcalcifications was found to be significantly better on digital mammography compared to film-screen mammography, there was no significant advantage of digital mammography resulting from the higher contrast resolution nor a disadvantage in terms of characterization of microcalcifications resulting from the lower spacial resolution. The advantages of digital mammography (e. g. CAD-systems, archiving, dose reduction) can be used without a loss of diagnostic quality.

To determine the role of the scatter grid in digital full-field mammography with respect to image quality and dose and to compare the experimental results with initial clinical experience.A phantom consisting of 205 fields that enclose gold dots of different thickness and size (CD-Mam phantom, Medical Department, Nijmegen, Netherlands) was used for digital full-field mammography with the conventional grid module and a special gridless module. Four different breast thicknesses were simulated using Plexiglas as scatter material. First, the phantom was exposed at the parameter and dose settings automatically selected in each experimental setup (with and without grid). Subsequently, the phantom was exposed at the different simulated breast thicknesses using the gridless module in combination with the parameters automatically selected for the grid module. This was followed by a series of phantom mammograms obtained with the experimental setup reversed. The 16 mammograms were evaluated by 3 readers and the results compared considering breast thickness, radiation dose, and quality. The gridless module was used for preoperative labeling in 16 patients for comparison of mammograms obtained with and without a grid.For the same entrance dose used in routine mammography, digital mammography without grid is superior to digital mammography with grid when performed on simulated thin breasts (Plexiglas less than 3 cm), with no difference found when performed on simulated large breasts. The advantages of gridless mammography are more pronounced at a markedly reduced entrance dose (identical parenchymal dose without and with grid using the dose automatically selected for the gridless module). This tendency is confirmed by the initial clinical comparison.Gridless digital full-field mammography has the potential to reduce the dose further, in addition to already known mechanisms of dose reduction. However, the gridless system must be adjusted (markedly higher "switch-off dose" at the detector) to achieve an overall dose reduction since gridless mammography is inferior to grid mammography for identical doses at the detector plane.

The prospective investigation of the therapeutic effect of CT-guided intra-articular corticosteroid injection into inflammatory sacroiliac (SI) joints compared to conventional treatment with nonsteroidal anti-inflammatory drugs (NSAIDS) in children with juvenile spondyloarthropathy (jSpA) and the determination of the role of dynamic magnetic resonance imaging (MRI) in establishing the indication and monitoring the therapy.The study comprises 89 children with known jSpA who were diagnosed by MRI to have a unilateral or bilateral sacroiliitis. Therapy with NSAIDS was initiated or continued in all 89 patients. Four weeks after the diagnostic MRI, two groups were distinguished according to the clinical response to NSAIDS, with group 1 consisting of 33 responders and group 2 of 56 non-responders. The patients of group 2 were treated with CT-guided intra-articular corticosteroid injection (low-dose injection) while the therapy with NSAIDS was continued. A total of 83 SI joints were punctured without complications, 27 bilaterally and 29 unilaterally. The indication for the intervention was based on inflammatory activity as determined by MRI. The therapy was monitored by clinical follow-up every 8 to 12 weeks over a period of 20 months. Follow-up by dynamic MRI was performed in all 56 children of group 2 and in 15 of the 33 children of group 1 within 8 +/- 4 months of the initial examination.A total of 87.5% of the children in group 2 showed a statistically significant decrease in their subjective complaints from 6.9 +/- 3.4 to 1.8 +/- 1.7 (p0.05) as measured on a visual analog scale (VAS from 0 to 10). Improvement was seen as early as 1.5 +/- 1.0 weeks after the intervention and lasted for a mean of 12 +/- 6 months. The children in group 1 already showed similar improvement of the VAS from 6.8 +/- 3.2 to 1.5 +/- 1.4 (p0.05) during the initial four weeks of NSAIDS therapy, with the improvement lasting for the 20-month observation period. The follow-up dynamic MRI (0.1 mmol/kg body weight) during therapy showed a statistically significant lower contrast-enhancement in both groups (group 1: 117 +/- 43 % versus 38 +/- 24 %, p0.05; group 2: 127 +/- 59 % versus 38 +/- 22 %, p0.05). One third of the patients of group 2 showed progression of joint destruction despite absence of subjective complaints.CT-guided intra-articular corticosteroid injection has proven an effective, symptomatic, and uncomplicated therapy of acute sacroiliitis in patients with jSpA. Dynamic MRI has a role in establishing the indication for intervention but its role for any follow-up is restricted to cases with inconclusive clinical response.

The use of digital full field mammography for imaging augmented breasts.Images of a sponge, as a tissue equivalent, partly covered with one of three different implants (silicone, silicone/saline, saline) were obtained using digital and film-screen technique. The visualisation of the sponge structure covered by the implant and next to the implant was evaluated by two radiologists. Results were compared to clinical results from 35 patients with implants.Two images with different parameter settings have to be obtained to visualize the covered sponge structure and the structure around the implant with film-screen technique. Digital mammography allows assessment of both areas using one image at different window settings. The assessability of covered structures depends on the type of implant. These results are in keeping with our clinical experiences.Digital mammography allows equal or better assessment of covered and non-covered tissue in augmented breasts without the need for additional exposures.

To evaluate the conspicuity of microcalcifications in magnified mammographic views of preparations obtained with full field digital mammography (FFDM), film-screen mammography (FSM), and the DIMA technique.Twelve preparations were examined by FFDM and FSM using 1.8 x magnification and DIMA using 7 x magnification. Parameter settings were identical for all three techniques. The number of visible microcalcifications was then determined for each modality by three radiologists. As far as possible, all preparations were X-rayed at 22 kV and 10 mAS.Altogether 9705 calcifications were counted (DIMA: 1609/1542/1534; FFDM: 1020/753/881; FSM: 901/643/822). The total number of microcalcifications identified with the DIMA technique was 4685 as compared to 2654 with FFDM and 2366 with FSM. The calcifications counted with FFDM and FSM thus corresponded to 56.6 % and 50.5 %, respectively, of those identified with DIMA. The differences between the groups were statistically significant (F-Test, p0.05).Significantly more calcifications are identified when magnified mammographic views of preparations containing microcalcifications are obtained with the DIMA technique compared to FFDM or FSM. FFDM depicts markedly more calcifications than FSM. This means one should increase spatial resolution. Digital mammography offers the potential for improved visualization of microcalcifications with advanced applications.

The aim of this survey was to determine improved diagnostics through digital mammography with assistance of computer algorithms and new investigation techniques.In general, the presented procedures are practicable with all digital mammography procedures. In our clinic the largest clinical experience exists with the only FDA certified full field mammography device Senograph 2000D (GE Medical Systems).First results from initial studies are shown, which are to evaluate the new procedures. The so-called post processing with visualization of microcalcifications, computer-assisted diagnosis, tomosynthesis, energy subtraction, contrast media in mammography and teleradiology are considered in particular.Digital mammography represents a promising procedure, opening new possibilities for improved diagnostic in mammography.

A procedure for performing intraoperative digital radiography of diagnostic breast specimens directly in the operating suite with teleradiologic assessment by a radiologist is presented. The efficiency of this procedure is compared with that of conventional magnification mammography performed in the radiology department.Thirty-six specimen radiographs obtained by conventional magnification mammography were compared with 38 intraoperative digital magnification radiographs (DIMA Soft P42 prototype, Feinfocus Inc., Garbsen). The radiographs were assessed for lesion conspicuity and time savings for the surgeon, anesthesiologist, and radiologist.The new procedure identified all 38 labeled pathological lesions, and the conventional technique likewise had a detection rate of 100% (36/36). The new technique resulted in considerable time savings for the surgeon and the radiologist. The duration of surgery was shorter and the time interval from removal of the specimen to reporting of the results was reduced from about 23 min to about 13 min. A single radiograph was sufficient for complete visualization of the specimen in all cases.Digital intraoperative specimen radiography considerably reduces the time of surgery depending on the local conditions and is highly accurate in locating a suspicious area within the tissue.

Digital full-field mammography has been used at the Department of Radiology of Charité Medical Center in Berlin since June 1999. This study compares the new digital technique with conventional mammography including a survey of its value in breast imaging and an outline of future prospects.More than 1,000 of a total of over 5,000 mammographies performed between June 1999 and April 2000 have been obtained using the digital full-field mammography system Senographe 2000D (GE Medical Systems). The digital mammograms were compared with previous conventional films and conventional mammographies performed during the same period (Philips UC Diagnost, Senographe DMRplus).Digital mammographies were equal to conventional ones in all cases and seemed to be superior in detecting microcalcifications in dense glandular tissue. Adequate assessment was possible despite the lower spatial resolution compared to conventional mammography. Additional magnified images were obtained with both techniques for differentiating microcalcifications.Digital full-field mammography appears to be at least equal to the conventional technique and even superior in some respects. In our experience, the lower spatial resolution of digital mammography has no major disadvantages. The digital system provides new options for electronic storage of mammograms, telemammography, and computer-aided diagnosis.

Standardized methods and instruments of medical documentation are prerequisites for quality assurance in medicine. Support for quality assurance measures at present can be attained by the programme systems ID DIACOS (encoding of diagnoses into ICD-9 and procedures into ICPM-GE) for daily clinical routine documentation. Administrative statistics, e.g. the L1-statistics of diagnoses according to section 16 Federal Statutory Instrument on Hospital Care Rates (BPflV) can be compiled without waste by aggregation. Supplementations of the programme system are planned caused by the introduction of new forms of Hospital reimbursement with changed classification patterns. An increasing need for computer-aided encoding will also result by the implementation of new classifications, e.g. ICD-10 and by the requirements concerning a scientific basic documentation (Selbmann, 1990; Mau, 1990) based partly on nomenclatures. The connection of the programme systems ID DIACOS and SNOMED (empirical and morphological analysis of medical texts) is possible and will be carried out (Hultsch, Diekmann, Ruhl, 1990).