Ocular Pulse Amplitude and Doppler Waveform Analysis in Glaucoma Patients

PURPOSE: To determine the correlation between ocular blood flow velocities and ocular pulse amplitude (OPA) in glaucoma patients using colour Doppler imaging (CDI) waveform analysis. METHOD: A prospective, observer-masked, case-control study was performed. OPA and blood flow variables from central retinal artery and vein (CRA, CRV), nasal and temporal short posterior ciliary arteries (NPCA, TPCA) and ophthalmic artery (OA) were obtained through dynamic contour tonometry and CDI, respectively. Univariate and multiple regression analyses were performed to explore the correlations between OPA and retrobulbar CDI waveform and systemic cardiovascular parameters (blood pressure, blood pressure amplitude, mean ocular perfusion pressure and peripheral pulse). RESULTS: One hundred and ninety-two patients were included [healthy controls: 55; primary open-angle glaucoma (POAG): 74; normal-tension glaucoma (NTG): 63]. OPA was statistically different between groups (Healthy: 3.17 ± 1.2 mmHg; NTG: 2.58 ± 1.2 mmHg; POAG: 2.60 ± 1.1 mmHg; p < 0.01), but not between the glaucoma groups (p = 0.60). Multiple regression models to explain OPA variance were made for each cohort (healthy: p < 0.001, r = 0.605; NTG: p = 0.003, r = 0.372; POAG: p < 0.001, r = 0.412). OPA was independently associated with retrobulbar CDI parameters in the healthy subjects and POAG patients (healthy CRV resistance index: β = 3.37, CI: 0.16-6.59; healthy NPCA mean systolic/diastolic velocity ratio: β = 1.34, CI: 0.52-2.15; POAG TPCA mean systolic velocity: β = 0.14, CI 0.05-0.23). OPA in the NTG group was associated with diastolic blood pressure and pulse rate (β = -0.04, CI: -0.06 to -0.01; β = -0.04, CI: -0.06 to -0.001, respectively). CONCLUSIONS: Vascular-related models provide a better explanation to OPA variance in healthy individuals than in glaucoma patients. The variables that influence OPA seem to be different in healthy, POAG and NTG patients

Monitoring international migration flows in Europe. Towards a statistical data base combining data from different sources

The paper reviews techniques developed in demography, geography and statistics that are useful for bridging the gap between available data on international migration flows and the information required for policy making and research. The basic idea of the paper is as follows: to establish a coherent and consistent data base that contains sufficiently detailed, up-to-date and accurate information, data from several sources should be combined. That raises issues of definition and measurement, and of how to combine data from different origins properly. The issues may be tackled more easily if the statistics that are being compiled are viewed as different outcomes or manifestations of underlying stochastic processes governing migration. The link between the processes and their outcomes is described by models, the parameters of which must be estimated from the available data. That may be done within the context of socio-demographic accounting. The paper discusses the experience of the U.S. Bureau of the Census in combining migration data from several sources. It also summarizes the many efforts in Europe to establish a coherent and consistent data base on international migration. The paper was written at IIASA. It is part of the Migration Estimation Study, which is a collaborative IIASA-University of Groningen project, funded by the Netherlands Organization for Scientific Research (NWO). The project aims at developing techniques to obtain improved estimates of international migration flows by country of origin and country of destination

Duodenal metastasis of alveolar soft part sarcoma

Aveolar soft part sarcoma is a rare tumor responsible for about 1% of all soft tissue sarcomas, affecting mostly adolescents and young adults. ASPS has curious patterns of metastatic spread, with seldom lymph node involvement. Lung, bone and brain are the most common metastatic places. Small bowel metastasis are infrequent, having found reported only one case of duodenal metastasis with polypous appearance. We describe a case of duodenal metastasis presenting as abdominal mass five years after initial diagnosis of alveolar soft part sarcoma

Multilevel use of image repository in the field of veterinary imaging and dissemination of training tools

[Extract] Until now the veterinary teaching environment is limited to static two dimensional materials. In order to improve the teaching experience we decided to adapt our educational PACS to build 2D and 3D viewing veterinary datasets. As entry level of education we setup a knowledge base consisting out of normal anatomy [1, 2]. The second step is the construction of an imaging atlas compared with the normal anatomy of every animal. The third step is the construction of a database containing a wide variety of radiopathology cases. The final level is the integration in an e-learning platform namely WikiVet [3] which is a collaborative initiative involving UK veterinary schools. The project is creating a comprehensive online knowledge base and will provide a reliable reference source to supersede Wikipedia for veterinary students, paramedics and graduates anywhere in the world, improving diagnostic skills using diagnostic imaging

Correlative Imaging in Gallbladder Carcinoma

Gallbladder carcinoma is a relatively rare malignant epithelial neoplasm, arising from gallbladder mucosa. It is the fifth most common gastrointestinal malignancy and the most common biliary tract cancer. Early diagnosis remains difficult, because clinical symptoms are sparse and non-specific, often resulting in advanced stage disease at the time of diagnosis. The most common feature of gallbladder carcinoma on different imaging modalities is focal wall thickening, associated with a large eccentric tumor mass. In this case we report the imaging characteristics of gallbladder carcinoma on ultrasound, MDCT and 18F-FDG PET/CT

The science of choice: an introduction

Introduction In October 2015, around 30 scholars convened at the Max Planck Institute for Demographic Research (MPIDR) in Rostock to discuss: (a) how individuals and families make decisions about marriage, child-birth, migration, retirement, and other transitions in the life course; and (b) how these decision processes can be operationalized in demographic models. The workshop was organized by the Scientific Panel on Microsimulation and Agent-Based Modelling con- vened by the International Union for the Scientific Study of Population (IUSSP) and by MPIDR. The report of this ‘Science of choice’ workshop and the papers presented are available from the workshop’s website (see IUSSP 2015). The five papers included in this Supplement are revised versions of papers presented at the workshop in Rostock

Micro-CT Based Experimental Liver Imaging Using a Nanoparticulate Contrast Agent: A Longitudinal Study in Mice

BACKGROUND: Micro-CT imaging of liver disease in mice relies on high soft tissue contrast to detect small lesions like liver metastases. Purpose of this study was to characterize the localization and time course of contrast enhancement of a nanoparticular alkaline earth metal-based contrast agent (VISCOVER ExiTron nano) developed for small animal liver CT imaging. METHODOLOGY: ExiTron nano 6000 and ExiTron nano 12000, formulated for liver/spleen imaging and angiography, respectively, were intravenously injected in C57BL/6J-mice. The distribution and time course of contrast enhancement were analysed by repeated micro-CT up to 6 months. Finally, mice developing liver metastases after intrasplenic injection of colon carcinoma cells underwent longitudinal micro-CT imaging after a single injection of ExiTron nano. PRINCIPAL FINDINGS: After a single injection of ExiTron nano the contrast of liver and spleen peaked after 4-8 hours, lasted up to several months and was tolerated well by all mice. In addition, strong contrast enhancement of abdominal and mediastinal lymph nodes and the adrenal glands was observed. Within the first two hours after injection, particularly ExiTron nano 12000 provided pronounced contrast for imaging of vascular structures. ExiTron nano facilitated detection of liver metastases and provided sufficient contrast for longitudinal observation of tumor development over weeks. CONCLUSIONS: The nanoparticulate contrast agents ExiTron nano 6000 and 12000 provide strong contrast of the liver, spleen, lymph nodes and adrenal glands up to weeks, hereby allowing longitudinal monitoring of pathological processes of these organs in small animals, with ExiTron nano 12000 being particularly optimized for angiography due to its very high initial vessel contrast