Twenty years of active bat rabies surveillance in Germany: a detailed analysis and future perspectives.

SUMMARY: In Germany, active bat rabies surveillance was conducted between 1993 and 2012. A total of 4546 oropharyngeal swab samples from 18 bat species were screened for the presence of EBLV-1- , EBLV-2- and BBLV-specific RNA. Overall, 0·15% of oropharyngeal swab samples tested EBLV-1 positive, with the majority originating from Eptesicus serotinus. Interestingly, out of seven RT-PCR-positive oropharyngeal swabs subjected to virus isolation, viable virus was isolated from a single serotine bat (E. serotinus). Additionally, about 1226 blood samples were tested serologically, and varying virus neutralizing antibody titres were found in at least eight different bat species. The detection of viral RNA and seroconversion in repeatedly sampled serotine bats indicates long-term circulation of the virus in a particular bat colony. The limitations of random-based active bat rabies surveillance over passive bat rabies surveillance and its possible application of targeted approaches for future research activities on bat lyssavirus dynamics and maintenance are discussed.

[Effort, accuracy and histology of MR-guided vacuum biopsy of suspicious breast lesions--retrospective evaluation after 389 interventions]. / Aufwand, Zuverlässigkeit und histologische Ergebnisse der MR-gesteuerten Vakuumbiopsie suspekter Mammabefunde--retrospektive Auswertung von 389 Interventionen.

The aim of this study was to evaluate the effort, accuracy, histological diagnoses and value of MR-guided vacuum biopsy (10-gauge, 9-gauge) as the diagnostic procedure for suspicious breast lesions visible on MRI alone. 389 MR-guided vacuum biopsies of suspicious MRM findings were performed in 365 patients either with a Vacora system (10G, Bard Company) or an ATEC system (9G, Suros Company). The retrospective study included the number of specimens, the table time, the complication rate, and the histopathological results for open biopsy and the findings after follow-up. The study included 341 unilateral unilocular, 12 unilateral bilocular and 12 bilateral unilocular MR-guided vacuum biopsies. In 27 patients (3.9%) the planned intervention was canceled because the lesion could not be reproduced. The average number of specimens was 15.1 (range 4 - 75) with the 10G technique and 14.6 (range 4 - 38) with the 9G technique. The table time was 43.2 min (range 17 - 95 min). Histology revealed concordant benign lesions in 231 cases (59.4%), borderline lesions in 50 cases (12.8%), malignant tumors in 106 cases (DCIS 30 [7.7%], invasive carcinoma 76 [19.5%]), and discordant findings in 2 cases (0.5%). The complication rate was less than 1%. MR-guided vacuum biopsy of the breast is an effective method for the minimally invasive percutaneous evaluation of suspicious breast lesions seen on MRI alone. As a consequence, primary open biopsy can be avoided and the rate of unnecessary surgical interventions reduced. There were no major differences between 10G and 9G vacuum biopsy systems.

Early mammographic and sonographic findings after intraoperative radiotherapy (IORT) as a boost in patients with breast cancer.

The aim of this study was to evaluate mammographic and sonographic changes at the surgical site within the first 2 years after IORT as a boost followed by whole-breast radiotherapy (WBRT), compared with a control group treated with WBRT alone. All patients had breast-conserving surgery for early-stage breast cancer. Group A: n = 27, IORT (20 Gy) followed by WBRT (46 Gy). Group B (control group): n = 27, WBRT alone (56-66 Gy). Mammography: fat necrosis in 14 group A versus four group B patients (P < 0.001); parenchymal scarring classified as unorganized at the last follow-up in 16 vs seven cases, respectively (P = 0.03). Ultrasound: overall number of patients with circumscribed findings 27 vs 18 (P < 0.001); particular hematomas/seromas in 26 vs 13 patients (P < 0.001). Synopsis of mammography and ultrasound: overall postoperative changes were significantly higher classified in group A (P = 0.01), but not judged to have a significantly higher impact on interpretation. Additional diagnostic procedures, due to unclear findings at the surgical site, were performed on four patients of both groups. Within the first 2 years after IORT as a boost, therapy-induced changes at the original tumor site are significantly more pronounced compared with a control group. There is no evidence that the interpretation of findings is complicated after IORT.

[Quality assurance with teleradiology]. / Qualitätssicherung mit Teleradiologie.

Teleradiology offers many applications for quality assurance in medicine. The spectrum reaches from electronic consultations in emergency or special cases and double reading--along with new models of cooperative work and medical networks--to technical quality assurance and integration into interinstitutional and patient controlled health records. Regional teleradiology networks based on server concepts can fulfill the developing technical and organisational requirements. The increasing mobility arising from smaller radiological equipment and improved accessibility to experts with minimized visualisation and reporting systems will change the radiological world of tomorrow, especially in combination with the usage of knowledge based systems in reference data bases and computer assisted diagnosis (CAD). Teleradiology by itself must be liable to quality assurance measurements to prevent unnecessary radiation exposure or danger to the doctor patient relation.

High performance thermoelectric Tl9BiTe6 with an extremely low thermal conductivity.

Tl 9BiTe (6) exhibits a thermoelectric figure of merit of ZT approximately 1.2 around 500 K, which significantly exceeds the state-of-the-art materials in this temperature range. The extraordinary thermoelectric performance is mainly due to the extremely low thermal conductivity of Tl 9BiTe (6) [ 0.39 W/(m times K) at 300 K]. In fact, the minimum lifetime of the phonons has to be taken into account to describe the thermal conductivity data.

International investigation of breast MRI: results of a multicentre study (11 sites) concerning diagnostic parameters for contrast-enhanced MRI based on 519 histopathologically correlated lesions.

A multicentre study was undertaken to provide fundamentals for improved standardization and optimized interpretation guidelines of dynamic contrast-enhanced MRI. Only patients scheduled for biopsy of a clinical or imaging abnormality were included. They underwent standardized dynamic MRI on Siemens 1.0 (163 valid lesions > or = 5 mm) or 1.5 T (395 valid lesions > or = 5 mm) using 3D fast low-angle shot (FLASH; 87 s) before and five times after standardized bolus of 0.2 mmol Gd-DTPA/kg. One-Tesla and 1.5 T data were analysed separately using a discriminant analysis. Only histologically correlated lesions entered the statistical evaluation. Histopathology and imaging were correlated in retrospect and in open. The best results were achieved by combining up to five wash-in or wash-out parameters. Different weighting of false-negative vs false-positive calls allowed formulation of a statistically based interpretation scheme yielding optimized rules for the highest possible sensitivity (specificity 30%), for moderate (50%) or high (64-71%) specificity. The sensitivities obtained at the above specificity levels were better at 1.0 T (98, 97, or 96%) than at 1.5 T (96, 93, 86%). Using a widely available standardized MR technique definition of statistically founded interpretation rules is possible. Choice of an optimum interpretation rule may vary with the clinical question. Prospective testing remains necessary. Differences of 1.0 and 1.5 T are not statistically significant but may be due to pulse sequences.

Relevance of sonographic B-mode criteria and computer-aided ultrasonic tissue characterization in differential/diagnosis of solid breast masses.

We aimed to evaluate the differential diagnostic value of a method of computer-assisted texture analysis in comparison to established ultrasonographic B-mode characteristics in the examination of solid breast masses. At two centers, 77 patients presenting with a solid mass on B-mode scan were studied at 7.5 MHz. Description of B-mode appearance included assessment of tumor shape, borders, presence of an echogenic rim, tissue architecture, internal echo structure, absorption and elasticity. For statistical pattern recognition, the following parameters were used: form factor, mean grey level, signal-to-noise ratio, mean gradient and correlation from the co-occurrence matrix. At center 1, the most decisive parameter for differential diagnosis was distortion of tissue architecture (sensitivity, SN, 83%; specificity, SP, 92%) and, at center 2, relation to the adjacent tissue (SN 93%, SP 92%). Among texture parameters, best discrimination was achieved for correlation from the co-occurrence matrix at center 1 (SN 58%, SP 73%) and for form factor at center 2 (SN 93%, SP 77%). Among sonographic criteria, the highest contribution to the diagnosis was found for an unsharp border (odds ratio, OR, 12.2), architectural distortion (OR, 8.6), fixation to skin or chest wall (OR, 9.0) and fixation to adjacent breast parenchyma (OR, 8.8), according to texture analysis for parameters form factor (OR 4.0) and correlation from the co-occurrence matrix (OR 4.7). Ultrasonographic texture analysis can be helpful as an additional parameter in differential diagnosis of breast tumors, but did not reach differential diagnostic accuracy of sonomorphologic features.

The Consortium of Graduate Medical Schools in Australia: formal and informal collaboration in medical education.

CONTEXT: In 1996-97 three Australian medical schools adopted 4-year graduate medical courses. The schools formed a consortium to establish common admissions processes and to collaborate on curriculum and staff development. OUTCOMES: ADMISSIONS: Outcomes in admissions included the construction of an entry test and agreement on common application procedures. Structured interviews and measures of prior tertiary performance were adopted in each school with some local variations. Formal structures were put into place to manage the development of the test and admissions procedures. OUTCOMES: CURRICULUM AND STAFF DEVELOPMENT: No formal structures were put into place for curriculum and staff development. While the advantages of common approaches were recognised, it was accepted that it was also important to generate local ownership and commitment to the new courses. Outcomes of educational consortia should not be judged solely by the nature of joint ventures but by the way in which membership of the consortium changes the priorities and practices within the institutions. Examples of the operation of this principle within the three schools include: use of visiting experts to refine and modify approaches to problem-based learning; use of staff from partner institutions to facilitate implementation of the courses; sharing information technology expertise; cooperation in the construction of feedback mechanisms, and sharing advice on fulfilling accreditation requirements. CONCLUSION: The Consortium has had an important impact on Australian medical education. There is a need for further analysis of the two methods of operation of the consortium, formal and informal, and their relation to its overall functioning.

[Lymph node imaging with ultra-rapid 3D MR angiography]. / Lymphknotendarstellung bei ultraschneller 3D-MR-Angiographie.

PURPOSE: A report on observations of lymph node images obtained by gadolinium-enhanced 3D MR angiography (MRA). METHODS: Ultrarapid MRA (TR, TE, FA-5 or 6.4 ms, 1.9 or 2.8 ms, 30-40 degrees) with 0.2 mmol/kg BW Gd-DTPA and 20 ml physiological saline. Start after completion of injection. Single series of the pelvis-thigh as well as head-neck regions by use of a phased array coil with a 1.5 T Magnetom Vision or a 1.0 T Magnetom Harmony (Siemens, Erlangen). We report on lymph node imaging in 4 patients, 2 of whom exhibited benign changes and 2 further metastases. In 1 patient with extensive lymph node metastases of a malignant melanoma, color-Doppler sonography as color-flow angiography (CFA) was used as a comparative method. RESULTS: Lymph node imaging by contrast medium-enhanced ultrarapid 3D MRA apparently resulted from their vessels. Thus, arterially-supplied metastases and inflammatory enlarged lymph nodes were well visualized while those with a.v. shunts or poor vascular supply in tumor necroses were poorly imaged. CONCLUSIONS: Further investigations are required with regard to the visualization of lymph nodes in other parts of the body as well as a possible differentiation between benign and malignant lesions.

[Optimal expansion of the multi-link stent. An in vitro study with high resolution roentgen technique]. / Optimierte Expansion des Multi-Link-Stents. Eine In-vitro-Untersuchung mittels hochauflösender Röntgentechnik.

It has been speculated that high pressure implantation may improve the results of coronary stenting. However, this method bears the risk of persistent dissection and may increase late lumen loss. Presently, there is no consensus about the optimal stent implantation technique with the regard to balloon size and pressure. To elucidate this question an experimental study was performed in a coronary stenosis model. 3.5 mm Multi-Link (ML) stents were implanted in 3.3 mm silicone rubber tubes containing 50% concentric narrowings. Three implantation techniques were applied: 1. The standard technique using the conventional ML delivery system with a compliant balloon (ML-ST). 2. A new deployment method with a high pressure delivery system (ML-HP). 3. "Focal postdilation" using the ARC catheter, which has a special balloon with an inner compliant and an outer non-compliant section (ML-ARC). For comparison, the Palmaz-Schatz stent was implanted by using a high pressure balloon. Stent expansion was imaged by magnification radiography. Minimal lumen diameter within the stent (MLD) and the lumen diameter outside the stent (BD) were measured after dilations with 6, 9, 12, 15, 18, and 21 atm. The relation of the BD to the MLD was used as an index of vessel trauma. The results lead to the following conclusions: 1. A complete apposition to the vessel wall for a balloon/vessel relation of 1.1:1 could not be reached with pressures below 9-15 atm. The increase of the pressure beyond 15 atm resulted only in a minimal additional lumen. 2. Compared to the Palmaz-Schatz stent the recoil of the ML stent was significantly lower. 3. For all three implantation techniques the ML-ARC showed the best results with the maximal dilation of the stenotic vessel-area and the minimal expansion of the vessel outside the stent.

[A multicenter study of diagnostic criteria in ultrasound mammography. Statistical pitfalls and ways out of the data jungle]. / Eine multizentrische Studie zu diagnostischen Kriterien in der Mammasonographie. Statistische Fallstricke und Wege aus dem Datendschungel.

This paper demonstrates the statistical processing of data from a multicentric study. Seventy-seven patients with a suspicious, solid breast mass were included in a two-center study, using clinical breast examination, mammography, and ultrasound. The assessment was formalized using a uniform evaluation sheet. The prospective results of the examinations were compared with the histologic report. The degree of interdependence between an examiner's diagnosis and diagnostic criteria used was assessed using the kappa statistics. We found that despite standardized assessment, the criteria used for differential diagnosis were at least partially different. The criteria valid for diagnosis at both centers were whether a mass fitted well into the surrounding tissue or led to destruction or architectural distortion, whether it was fixed to the surrounding tissues, as assessed by sonopalpation maneuvers, and whether it borders were sharp or unsharp.

A selection test for Australian graduate-entry medical schools.

One of the selection criteria for the three Australian medical schools with graduate-entry programs is performance in a common entry test, the Graduate Australian Medical School Admissions Test (GAMSAT). We found that scores for GAMSAT in 1996 (its second year) varied significantly with candidate sex, age, highest degree level and main subject in first degree. Mean scores were highest for men, younger candidates, honours graduates and those with a physical sciences background. However, arts and social sciences graduates (9.8% of applicants) comprised 11.4% of the 200 top-scoring candidates.

[Development of a clinical-radiological CD-ROM database for focal lesions of the liver]. / Aufbau einer klinisch-radiologischen CD-ROM-Datenbank am beispiel fokaler Leberläsionen.

PURPOSE: The development of a CD-ROM database for continuous acquisition and archiving of interesting radiologic cases is described. As a pilot study radiologic images of focal lesions of the liver were collected. METHODS: The database runs on a PC (80486 DX2, 66 MHz, 16 MB RAM), which is connected to the clinic network, a high quality x-ray scanner and a CD-ROM writer. Radiologic images can be inserted into the database either by scanner or by image transfer via network. The database is designed using Access 2.0. Well documented cases were chosen retrospectively, manipulated and archived. RESULTS: 308 images of 12 focal lesions with a capacity of 802 MB were stored on CD-ROM. Per case a storage capacity of 40-75 MB is necessary for image raw material, 15-25 MB are necessary for the postprocessed data. Spatial resolution is 190 dpi (3000 pixel/40 cm). Clinical data, radiological diagnosis coded by modified ACR index and a compressed icon of the images are stored on PC, the image data are stored on CD-ROM. 2.5 hours per case are needed for the complete acquisition, manipulation and archiving procedure, but improved hardware configuration can reduce the time significantly. CONCLUSION: The described database allows continuous archiving of interesting radiologic cases on PC. ACR index is suited for a quick search of a specific combination of radiologic images and diagnosis from different modalities.

Oxygenation of mammary tumors as evaluated by ultrasound-guided computerized-pO2-histography.

The average pO2 in breast carcinomas in situ is significantly lower than that in the normal breast tissue. The mean pO2 value for benign breast tumors is significantly higher than that of the breast cancers but lies significantly lower than the corresponding normal breast. No significant differences are found in the mean pO2 values when comparing cancers of different stages and histology. A decrease in the mean pO2 value is measured from the periphery to the center of the breast tumors investigated. The average pO2 values for pre- and postmenopausal patients differ significantly. The described method provides a reliable assessment of tissue pO2 in situ with a minimum of discomfort. Due to extensive inter tumor heterogeneity, prediction of pO2 values for tumors of same stage and same histology is not possible, so that measurement of individual tumor is mandatory for determining therapy response.

[Localization of non-palpable lesions by mammography for preoperative marking and tissue removal]. / Lokalisation nicht-palpabler Läsionen in der Mammographie zur präoperativen Markierung und Gewebe-Entnahme.

Mammography screening can increase survival by 15-50%. Minute nonpalpable breast carcinomas can be detected and surgically removed using precise localization techniques. Various techniques are shown, including localization by means of grid mammography and conventional localization with several needles. Stereotactic localization is recommended if the focus cannot be detected by sonography--a procedure now almost always possible if mammography units have the necessary additional equipment. In future it will often become necessary, following a good response to pre-operative chemotherapy, for the tumor, which as a result has become nonpalpable, to be marked prior to surgery (e.g. remaining microcalcifications). This is essential if a representative area of tissue is to be made available for histological examination.