排序方式: 共有61条查询结果,搜索用时 31 毫秒
41.
Mammographic finding as predictor of survival in 1-9 mm invasive breast cancers. worse prognosis for cases presenting as calcifications alone 总被引:1,自引:0,他引:1
PURPOSE: To investigate breast cancer survival in small invasive breast cancers in relation to mammographic findings. MATERIALS AND METHODS: We investigated a consecutive series of 96 cases of 1-9mm small invasive breast cancers diagnosed 1988-1994. Median follow-up of the survivors was 7 years (range: 4.5-10.5). Mammographic findings were classified into rounded masses, spiculated masses, calcifications (casting or pleomorphic) and masses combined with calcifications. Lymph node status and histological malignancy grade were also evaluated. Eight year survival rate in breast cancer was estimated with the Kaplan-Meier method and risk of death with proportional-hazards regression. RESULTS: 6/96 women died from breast cancer. 3/14 had calcifications alone, 2/56 with spiculated masses, 1/12 with rounded masses. 5/78 who died were node-negative cancers and 1/4 was node-positive. The survival rate for the whole group was 93%: 77% for the calcifications alone group, 95% for spiculated masses and 91% for rounded masses. The survival rate for the node-negative cancers was 92% compared to 75% for node-positive cancers. Calcifications alone (p = 0.01) and node positivity (p =0.03) had each independent significant higher risk of death taking finding, node status and grade into account. CONCLUSION: Small invasive breast cancers mammographically presenting as casting or pleomorphic calcifications alone have a significantly worse prognosis than other types. 相似文献
42.
Jyrki MP. Lötjönen Robin Wolz Juha R. Koikkalainen Lennart Thurfjell Gunhild Waldemar Hilkka Soininen Daniel Rueckert 《NeuroImage》2010,49(3):2352-2365
We introduce an optimised pipeline for multi-atlas brain MRI segmentation. Both accuracy and speed of segmentation are considered. We study different similarity measures used in non-rigid registration. We show that intensity differences for intensity normalised images can be used instead of standard normalised mutual information in registration without compromising the accuracy but leading to threefold decrease in the computation time. We study and validate also different methods for atlas selection. Finally, we propose two new approaches for combining multi-atlas segmentation and intensity modelling based on segmentation using expectation maximisation (EM) and optimisation via graph cuts. The segmentation pipeline is evaluated with two data cohorts: IBSR data (N = 18, six subcortial structures: thalamus, caudate, putamen, pallidum, hippocampus, amygdala) and ADNI data (N = 60, hippocampus). The average similarity index between automatically and manually generated volumes was 0.849 (IBSR, six subcortical structures) and 0.880 (ADNI, hippocampus). The correlation coefficient for hippocampal volumes was 0.95 with the ADNI data. The computation time using a standard multicore PC computer was about 3–4 min. Our results compare favourably with other recently published results. 相似文献
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Koikkalainen J Lötjönen J Thurfjell L Rueckert D Waldemar G Soininen H;Alzheimer's Disease Neuroimaging Initiative 《NeuroImage》2011,56(3):1429-1144
In this paper methods for using multiple templates in tensor-based morphometry (TBM) are presented and compared to the conventional single-template approach. TBM analysis requires non-rigid registrations which are often subject to registration errors. When using multiple templates and, therefore, multiple registrations, it can be assumed that the registration errors are averaged and eventually compensated. Four different methods are proposed for multi-template TBM. The methods were evaluated using magnetic resonance (MR) images of healthy controls, patients with stable or progressive mild cognitive impairment (MCI), and patients with Alzheimer's disease (AD) from the ADNI database (N=772). The performance of TBM features in classifying images was evaluated both quantitatively and qualitatively. Classification results show that the multi-template methods are statistically significantly better than the single-template method. The overall classification accuracy was 86.0% for the classification of control and AD subjects, and 72.1% for the classification of stable and progressive MCI subjects. The statistical group-level difference maps produced using multi-template TBM were smoother, formed larger continuous regions, and had larger t-values than the maps obtained with single-template TBM. 相似文献
45.
Barbro Thurfjell Mona Eliasson Ingemar Swenne Anne-Liis von Knorring Ingemar Engström 《Eating disorders》2013,21(4):287-304
Clinical features have low predictive value for the outcome of eating disorders. This study focuses on the possible predictive value of gender ideals. Data was from adolescent girls thoroughly assessed both at presentation and at a three-year follow up. Few variables differed between the outcome groups. However, perceptions of gender ideals, as measured by the Three Questions of Ideals, were found to contribute to the prediction of outcome. A discriminant analysis showed that gender ideals, maturity fears, sexual debut, and vomiting were significant discriminators in a set of factors, which correctly classified the outcome for 75.3% of the sample. 相似文献
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Jesper Leif Roger Andersson Lennart Thurfjell 《European journal of nuclear medicine and molecular imaging》1999,26(7):718-733
We devised a method to allow for retrospective registration of tomographic images with very different information content,
the main emphasis being on sets of positron emission tomography images obtained with different tracers. A multivariate cost-function
based on information theory was used as an index of ”goodness-of-alignment”. The cost-function makes no assumptions regarding
the form of the relationship between the two image sets, and is hence very general. Image volumes, with known relative spatial
orientation, were simulated for tracers with different uptake patterns and the method was validated by assessing its ability
to recover these known orientations. The method was able to recover the known transformations with an accuracy of about 1 mm
and 1° along and around all axes, even for tracer combinations with radically different uptake patterns and with large initial
misalignment. With the suggested method it is feasible to retrospectively align examinations obtained with different tracers
and/or modalities.
Received 19 December 1998 and in revised form 9 February 1999 相似文献
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Lennart Thurfjell Marco Pagani Jesper L.R. Andersson Cathrine Jonsson Roger Lundqvist Anna Wagner 《Journal of neuroimaging》2000,10(1):39-46
Image registration brings images into a form in which each voxel corresponds to a predetermined anatomic entity and is necessary for comparisons of data across scans. Intrasubject registration is a matter of translating and rotating one image volume into correspondence with another. Intersubject registration is more difficult because it requires the removal of individual anatomy dependence from the data. This article describes, with the help of clinical examples, automated methods for intrasubject registration of scans within and between modalities, and intersubject registration used for registering a three-dimensional brain atlas with a patient's brain scan. 相似文献
50.
K. Sikk P. Taba S. Haldre J. Bergquist D. Nyholm H. Askmark T. Danfors J. Sörensen L. Thurfjell R. Raininko R. Eriksson R. Flink C. Färnstrand S.‐M. Aquilonius 《Acta neurologica Scandinavica》2010,121(4):237-243
Sikk K, Taba P, Haldre S, Bergquist J, Nyholm D, Askmark H, Danfors T, Sörensen J, Thurfjell L, Raininko R, Eriksson R, Flink R, Färnstrand C, Aquilonius S‐M. Clinical, neuroimaging and neurophysiological features in addicts with manganese‐ephedrone exposure. Acta Neurol Scand: 2010: 121: 237–243.© 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objective – To identify biomarkers supporting the clinical diagnosis of manganism in patients several years after exposure to manganese (Mn). Methods – Neurophysiological examinations, magnetic resonance imaging (MRI), single‐photon emission computed tomography and fluorodeoxyglycose (FDG) positron emission tomography were performed in four former ephedrone addicts with extrapyramidal symptoms. Results – Peripheral nervous system was not affected. No patients had reduced uptake of 123I Ioflupane in the striatum. MRI signal intensities were slightly changed in the basal ganglia. All patients showed a widespread, but not uniform, pathological pattern of FDG uptake with changes mainly located to the central part of the brain including the basal ganglia and the surrounding white matter. Conclusions – Presynaptic neurons in the nigrostriatal pathway are intact in Mn‐induced parkinsonism after prolonged abstinence from ephedrone. The diagnosis is principally based on clinical signs and the history of drug abuse. 相似文献