Publications de Peter Modregger

Dissecting abdominal aortic aneurysm in Ang II-infused mice: suprarenal branch ruptures and apparent luminal dilatation

Nikolaos Stergiopoulos, Patrick Segers, Jessica Sordet, Alessandra Piersigilli, Bram Trachet, Peter Modregger

Aims In this work, we provide novel insight into the morphology of dissecting abdominal aortic aneurysms in angiotensin II-infused mice. We demonstrate why they exhibit a large variation in shape and, unlike their human counterparts, are located suprarenal ...

Oxford University Press2015

Simultaneous submicrometric 3D imaging of the micro-vascular network and the neuronal system in a mouse spinal cord

Giuseppe Battaglia, Peter Modregger

Faults in vascular (VN) and neuronal networks of spinal cord are responsible for serious neurodegenerative pathologies. Because of inadequate investigation tools, the lacking knowledge of the complete fine structure of VN and neuronal system represents a c ...

Nature Publishing Group2015

Simple merging technique for improving resolution in qualitative single image phase contrast tomography

Peter Modregger, Marco Stampanoni, Zheng Wang

For dynamic samples and/or for simple ease-of-use experiments, single-image phase contrast tomography is a very effective method for the 3D visualization of materials which would otherwise be indiscernible in attenuation based x-ray imaging. With binary sa ...

Optical Society of America2014

Combining Monte Carlo methods with coherent wave optics for the simulation of phase-sensitive X-ray imaging

Peter Modregger, Marco Stampanoni

Phase-sensitive X-ray imaging shows a high sensitivity towards electron density variations, making it well suited for imaging of soft tissue matter. However, there are still open questions about the details of the image formation process. Here, a framework ...

International Union of Crystallography2014

Living-Engineered Valves for Transcatheter Venous Valve Repair

Peter Modregger, Marco Stampanoni

Background: Chronic venous insufficiency (CVI) represents a major global health problem with increasing prevalence and morbidity. CVI is due to an incompetence of the venous valves, which causes venous reflux and distal venous hypertension. Several studies ...

2014

Two-dimensional ultra-small angle X-ray scattering with grating interferometry

Simon Rutishauser, Christian David, Peter Modregger, Marco Stampanoni

It was recently established that the pixel-wise ultra-small angle x-ray distribution can be retrieved with grating interferometry. However, in these one dimensional approaches the contrast was limited to the direction orthogonal to the structure of the lin ...

AIP American Institute of Physics2014

Multiple Scattering Tomography

Christian David, Peter Modregger, Marco Stampanoni

Multiple scattering represents a challenge for numerous modern tomographic imaging techniques. In this Letter, we derive an appropriate line integral that allows for the tomographic reconstruction of angular resolved scattering distributions, even in the p ...

Amer Physical Soc2014

Differential X-ray phase contrast tomography of Alzheimer plaques in mouse models: perspectives for drug development and clinical imaging techniques

Peter Modregger, Marco Stampanoni

Alzheimer's disease (AD) is a looming threat on an ever-ageing population, with devastating effects on the human intellect. A particular characteristic lesion - the extracellular amyloid plaque - accumulates in the brain of AD patients during the course of ...

Institute of Physics2013

Iterative FBP For Improved Reconstruction Of X-Ray Differential Phase-Contrast Tomograms

Michaël Unser, Cédric René Jean Vonesch, Masih Nilchian, Peter Modregger, Marco Stampanoni

X-ray differential phase-contrast tomography is a recently-developed modality for the imaging of low-contrast biological samples. Its mathematical model is based on the first derivative of the Radon transform and the images, in practice, are reconstructed ...

IEEE2013

Multi-disciplinary characterization and monitoring of sandstone (Kandla Grey) under different external conditions

Steven Luc X Peetermans, Peter Modregger, Marco Stampanoni

Geological Society2013

Constrained regularized reconstruction of X-ray-DPCI tomograms with weighted-norm

Michaël Unser, Cédric René Jean Vonesch, Masih Nilchian, Stamatios Lefkimmiatis, Peter Modregger, Marco Stampanoni

In this paper we introduce a new reconstruction algorithm for X-ray differential phase-contrast Imaging (DPCI). Our approach is based on 1) a variational formulation with a weighted data term and 2) a variable-splitting scheme that allows for fast converge ...

Optical Society of America2013

Off-the-shelf human decellularized tissue-engineered heart valves in a non-human primate model

Chad Brokopp, Peter Modregger, Marco Stampanoni

Heart valve tissue engineering based on decellularized xenogenic or allogenic starter matrices has shown promising first clinical results. However, the availability of healthy homologous donor valves is limited and xenogenic materials are associated with i ...

Elsevier2013

Fast iterative reconstruction of differential phase contrast X-ray tomograms

Michaël Unser, Cédric René Jean Vonesch, Masih Nilchian, Peter Modregger, Marco Stampanoni

Differential phase-contrast is a recent technique in the context of X-ray imaging. In order to reduce the specimen's exposure time, we propose a new iterative algorithm that can achieve the same quality as FBP-type methods, while using substantially fewer ...

Optical Society of America2013

A sensitive x-ray phase contrast technique for rapid imaging using a single phase grid analyzer

Simon Rutishauser, Christian David, Peter Modregger, Marco Stampanoni

Phase contrast x-ray imaging (PCXI) is a promising imaging modality, capable of sensitively differentiating soft tissue structures at high spatial resolution. However, high sensitivity often comes at the cost of a long exposure time or multiple exposures p ...

Optical Society of America2013

Three-dimensional pore structure and ion conductivity of porous ceramic diaphragms

Jelena Stojadinovic, Harald Hagendorfer, Laura Victoria Suárez Murillo, Peter Modregger, Andreas Züttel

Wiley-Blackwell2013

Imaging brain amyloid deposition using grating-based differential phase contrast tomography

Patrick Aebischer, Jean-Charles Bensadoun, Peter Modregger, Marco Stampanoni

One of the core pathological features of Alzheimer's disease (AD) is the accumulation of amyloid plaques in the brain. Current efforts of medical imaging research aim at visualizing amyloid plaques in living patients in order to evaluate the progression of ...

Elsevier2012

Prenatally engineered autologous amniotic fluid stem cell-based heart valves in the fetal circulation

Marc Farine, Chad Brokopp, Peter Modregger, Markus Rudin, Marco Stampanoni

Prenatal heart valve interventions aiming at the early and systematic correction of congenital cardiac malformations represent a promising treatment option in maternal-fetal care. However, definite fetal valve replacements require growing implants adaptive ...

2012

A tilted grating interferometer for full vector field differential x-ray phase contrast tomography

Simon Rutishauser, Christian David, Peter Modregger, Marco Stampanoni

We report on a setup for differential x-ray phase-contrast imaging and tomography, that measures the full 2D phase-gradient information. The setup uses a simple one-dimensional x-ray grating interferometer, in which the grating structures of the interferom ...

Optical Society of America2012

Imaging the Ultrasmall-Angle X-Ray Scattering Distribution with Grating Interferometry

Christian David, Peter Modregger, Marco Stampanoni

American Physical Society2012

Engineering of living autologous human umbilical cord cell-based septal occluder membranes using composite PGA-P4HB matrices

Peter Modregger, Marco Stampanoni

Interventional closure of intracardiac wall defects using occluder devices has evolved as a highly attractive treatment option. However, incomplete and delayed healing reactions often result in a major risk of residual defects, thromboembolism, or device f ...

2011