| 1. |
- Cserni, G, et al.
(author)
-
Consistency in recognizing microinvasion in breast carcinomas is improved by immunohistochemistry for myoepithelial markers.
- 2016
-
In: Virchows Archiv: an international journal of pathology. - : Springer Science and Business Media LLC. - 1432-2307. ; 468:4, s. 473-481
-
Journal article (peer-reviewed)abstract
- Microinvasion is the smallest morphologically identifiable stage of invasion. Its presence and distinction from in situ carcinoma may have therapeutic implications, and clinical staging also requires the recognition of this phenomenon. Microinvasion is established on the basis of several morphological criteria, which may be difficult and not perfectly reproducible among pathologists. The aim of this study was to assess the consistency of diagnosing microinvasion in the breast on traditional haematoxylin and eosin (HE) stained slides and to evaluate whether immunohistochemistry (IHC) for myoepithelial markers could improve this. Digital images were generated from representative areas of 50 cases stained with HE and IHC for myoepithelial markers. Cases were specifically selected from the spectrum of in situ to microinvasive cancers. Twenty-eight dedicated breast pathologists assessed these cases at different magnifications through a web-based platform in two rounds: first HE only and after a washout period by both HE and IHC. Consistency in the recognition of microinvasion significantly improved with the use of IHC. Concordance rates increased from 0.85 to 0.96, kappa from 0.5 to 0.85, the number of cases with 100 % agreement rose from 9/50 to 25/50 with IHC and the certainty of diagnosis also increased. The use of IHC markedly improves the consistency of identifying microinvasion. This corroborates previous recommendations to use IHC for myoepithelial markers to clarify cases where uncertainty exists about the presence of microinvasion. Microinvasive carcinoma is a rare entity, and seeking a second opinion may avoid overdiagnosis.
|
|
| 2. |
|
|
| 3. |
- Schmid, F., et al.
(author)
-
Bidirectional tensile testing cell for in situ small angle X-ray scattering investigations of soft tissue
- 2006
-
In: Nuclear Instruments and Methods in Physics Research Section B. - : Elsevier BV. - 0168-583X .- 1872-9584. ; 246:1, s. 262-268
-
Journal article (peer-reviewed)abstract
- An X-ray cell for the acquisition of one-dimensional mechanical force-displacement diagrams of soft tissue samples has been developed. The combination of X-ray and mechanical data allows new insights into the coupling of the macroscopic behavior and nanoscopic structural changes during the application of load. Two linear mu-translation stages are used to symmetrically - i.e. bidirectionally - stretch the sample. A video-extensometer is installed to record geometrical changes of the sample during measurement which allows to determine true stresses and strains. The sample can be immersed in a liquid and heated. We demonstrate the advantages over common unidirectional tensile testing devices without length measurement systems by comparing different mechanical and diffraction data sets of human arterial tissue.
|
|
| 4. |
- Schmid, F., et al.
(author)
-
In situ tensile testing of human aortas by time-resolved small-angle X-ray scattering
- 2005
-
In: Journal of Synchrotron Radiation. - 0909-0495 .- 1600-5775. ; 12, s. 727-733
-
Journal article (peer-reviewed)abstract
- The collagen diffraction patterns of human aortas under uniaxial tensile test conditions have been investigated by synchrotron small- angle X- ray scattering. Using a recently designed tensile testing device the orientation and d- spacing of the collagen fibers in the adventitial layer have been measured in situ with the macroscopic force and sample stretching under physiological conditions. The results show a direct relation between the orientation and extension of the collagen fibers on the nanoscopic level and the macroscopic stress and strain. This is attributed first to a straightening, second to a reorientation of the collagen fibers, and third to an uptake of the increasing loads by the collagen fibers.
|
|
| 5. |
- Wilson, A. R. M., et al.
(author)
-
The requirements of a specialist Breast Centre
- 2013
-
In: European Journal of Cancer. - : Elsevier BV. - 0959-8049 .- 1879-0852. ; 49:17, s. 3579-3587
-
Journal article (peer-reviewed)abstract
- Introduction: In recognition of the advances and evidence based changes in clinical practice that have occurred in recent years and taking into account the knowledge and experience accumulated through the voluntary breast unit certification programme, Eusoma has produced this up-dated and revised guidelines on the requirements of a Specialist Breast Centre (BC). Methods: The content of these guidelines is based on evidence from the recent relevant peer reviewed literature and the consensus of a multidisciplinary team of European experts. The guidelines define the requirements for each breast service and for the specialists who work in specialist Breast Centres. Results: The guidelines identify the minimum requirements needed to set up a BC, these being an integrated Breast Centre, dealing with a sufficient number of cases to allow effective working and continuing expertise, dedicated specialists working with a multidisciplinary approach, providing all services throughout the patients pathway and data collection and audit. It is essential that the BC also guarantees the continuity of care for patients with advanced (metastatic) disease offering treatments according to multidisciplinary competencies and a high quality palliative care service. The BC must ensure that comprehensive support and expertise may be needed, not only through the core BC team, but also ensure that all other medical and paramedical expertise that may be necessary depending on the individual case are freely available, referring the patient to the specific care provider depending on the problem. Conclusions: Applying minimum requirements and quality indicators is essential to improve organisation, performance and outcome in breast care. Efficacy and compliance have to be constantly monitored to evaluate the quality of patient care and to allow appropriate corrective actions leading to improvements in patient care. (C) 2013 Elsevier Ltd. All rights reserved.
|
|
| 6. |
- Auer, M., et al.
(author)
-
3-D reconstruction of tissue components for atherosclerotic human arteries using ex vivo high-resolution MRI
- 2006
-
In: IEEE Transactions on Medical Imaging. - : Institute of Electrical and Electronics Engineers (IEEE). - 0278-0062 .- 1558-254X. ; 25:3, s. 345-357
-
Journal article (peer-reviewed)abstract
- Automatic computer-based methods are well suited for the image analysis of the different components in atherosclerotic plaques. Although several groups work on such analysis some of the methods used are oversimplified and require improvements when used within a computational framework for predicting meaningful stress and strain distributions in the heterogeneous arterial wall under various loading conditions. Based on high-resolution magnetic resonance imaging of excised atherosclerotic human arteries and a series of two-dimensional (2-D) contours we present a segmentation tool that permits a three-dimensional (3-D) reconstruction of the most important tissue components of atherosclerotic arteries. The underlying principle of the proposed approach is a model-based snake algorithm for identifying 2-D contours, which uses information about the plaque composition and geometric data of the tissue layers. Validation of the computer-generated tissue boundaries is performed with 100 MR images, which are compared with the results of a manual segmentation performed by four experts. Based on the Hausdorff distance and the average distance for computer-to-expert differences and the interexpert differences for the outer boundary of the adventitia, the adventitia-media, media-intima, intima-lumen and calcification boundaries are less than 1 pixel (0.234 mm). The percentage statistic shows similar results to the modified Williams index in terms of accuracy. Except for the identification of lipid-rich regions the proposed algorithm is automatic. The nonuniform rational B-spline-based computer-generated 3-D models of the individual tissue components provide a basis for clinical and computational analysis.
|
|
| 7. |
- Auer, M., et al.
(author)
-
A methodology to study the morphologic changes in lesions during in vitro angioplasty using MRI and image processing
- 2008
-
In: Medical Image Analysis. - : Elsevier BV. - 1361-8415 .- 1361-8423. ; 12:2, s. 163-173
-
Journal article (peer-reviewed)abstract
- The assessment of morphologic changes in atherosclerotic lesions during interventional procedures such as transluminal balloon angioplasty is an issue of highest clinical importance. We propose a methodology that allows realistic 3D morphomechanical modeling of the vessel, the plaque and the lumen at different stages of in vitro angioplasty. We elaborate on a novel device designed to guide angioplasty under controlled experimental conditions. The device allows to reproduce in vivo conditions as good as possible, i.e. axial in situ pre-stretch, 100 mmHg intraluminal pressure, 37 degrees C Tyrode solution, balloon inflation without external constraints using a high-pressure syringe and contrast medium. With a standard 1.5 T MR-system we accomplish multi-spectral images at different stages of the angioplasty experiment. After MR image acquisition the specimen is used for histopathological analysis and biomechanical tests. A segmentation process is used to generate NURBS-based 3D geometric models of the individual vessel and plaque components at different balloon pressures. Tissue components are segmented automatically using generalized gradient vector flow active contours. We investigated 10 human femoral arteries. The effects of balloon compression on the individual artery components is particularly described for two obstructed arteries with an intact collagenous cap, a pronounced lipid pool and with calcification. In both arteries we observe a significant increase in lumen area after angioplasty. Dissection between intima and media and reduction of the lipid pool are primary mechanisms of dilatation. This methodology provides a basis for studying plaque biomechanics under supra-physiological loading conditions. It has the potential to improve and validate finite element models of atherosclerotic plaques which may allow a better prediction of angioplasty procedures.
|
|
| 8. |
- Auer, M., et al.
(author)
-
In Vitro Angioplasty of Atherosclerotic Human Femoral Arteries : Analysis of the Geometrical Changes in the Individual Tissues Using MRI and Image Processing
- 2010
-
In: Annals of Biomedical Engineering. - : Springer Science and Business Media LLC. - 0090-6964 .- 1573-9686. ; 38:4, s. 1276-1287
-
Journal article (peer-reviewed)abstract
- Existing atherosclerotic plaque imaging techniques such as intravascular ultrasound, multidetector computed tomography, optical coherence tomography, and high-resolution magnetic resonance imaging (hrMRI) require computerized methods to separate and analyze the plaque morphology. In this work, we perform in vitro balloon angioplasty experiments with 10 human femoral arteries using hrMRI and image processing. The vessel segments contain low-grade to high-grade lesions with very different plaque compositions. The experiments are designed to mimic the in vivo situation. We use a semi-automatic image processing tool to extract the three-dimensional (3D) geometries of the tissue components at four characteristic stages of the angioplasty procedure. The obtained geometries are then used to determine geometrical and mechanical indices in order to characterize, classify, and analyze the atherosclerotic plaques by their specific geometrical changes. During inflation, three vessels ruptured via helical crack propagation. The adventitia, media, and intima did not preserve their area/volume during inflation; the area changes of the lipid pool during inflation were significant. The characterization of changes in individual 3D tissue geometries, together with tissue-specific mechanical properties, may serve as a basis for refined finite element (FE) modeling, which is key to better understand stress evolution in various atherosclerotic plaque configurations.
|
|
| 9. |
- Cserni, Gabor, et al.
(author)
-
Distinction of isolated tumour cells and micrometastasis in lymph nodes of breast cancer patients according to the new Tumour Node Metastasis (TNM) definitions
- 2011
-
In: European Journal of Cancer. - : Elsevier BV. - 1879-0852 .- 0959-8049. ; 47:6, s. 887-894
-
Journal article (peer-reviewed)abstract
- Isolated tumour cells and micrometastases represent two different staging categories and are often dealt with differently when identified in sentinel lymph nodes of breast cancer patients. The reproducibility of these categories was found to be suboptimal in several studies. The new edition of the TNM (Tumour Node Metastasis) is expected to improve the reproducibility of these categories. Fifty cases of possible low-volume nodal involvement were represented by one to four digital images and were analysed by members of the European Working Group for Breast Screening Pathology (EWGBSP). The kappa value for interobserver agreement of the pN (TNM) staging categories and of the isolated tumour cells category were 0.55 and 0.56 reflecting moderate reproducibility, and the kappa of the micrometastatic category (0.62) reflected substantial reproducibility. This is an improvement over the results gained on the basis of the previous edition of the TNM. Maximal adherence to the category definitions supplemented by explanatory texts in the staging manual should result in more homogeneous nodal staging of breast cancer. (C) 2010 Elsevier Ltd. All rights reserved.
|
|
| 10. |
- Franceschini, G., et al.
(author)
-
Brain tissue deforms similarly to filled elastomers and follows consolidation theory
- 2006
-
In: Journal of the mechanics and physics of solids. - : Elsevier BV. - 0022-5096 .- 1873-4782. ; 54:12, s. 2592-2620
-
Journal article (peer-reviewed)abstract
- Slow, large deformations of human brain tissue-accompanying cranial vault deformation induced by positional plagiocephaly, occurring during hydrocephalus, and in the convolutional development-has surprisingly received scarce mechanical investigation. Since the effects of these deformations may be important, we performed a systematic series of in vitro experiments on human brain tissue, revealing the following features. (i) Under uniaxial (quasi-static), cyclic loading, brain tissue exhibits a peculiar nonlinear mechanical behaviour, exhibiting hysteresis, Mullins effect and residual strain, qualitatively similar to that observed in filled elastomers. As a consequence, the loading and unloading uniaxial curves have been found to follow the Ogden nonlinear elastic theory of rubber (and its variants to include Mullins effect and permanent strain). (ii) Loaded up to failure, the shape of the stress/strain curve qualitatively changes, evidencing softening related to local failure. (iii) Uniaxial (quasi-static) strain experiments under controlled drainage conditions provide the first direct evidence that the tissue obeys consolidation theory involving fluid migration, with properties similar to fine soils, but having much smaller volumetric compressibility. (iv) Our experimental findings also support the existence of a viscous component of the solid phase deformation. Brain tissue should, therefore, be modelled as a porous, fluid-saturated, nonlinear solid with very small volumetric (drained) compressibility.
|
|
