Research Activities

X-ray imaging

X-ray imaging is one of the most reliable among the non-invasive diagnostic techniques currently available in modern medicine. Indeed, it allows the radiologist to view the details of the internal structures of our body with a very fine spatial resolution (order of a tenth of a millimeter). Concerning Breast imaging, the most recent technological innovations now allow for the three-dimensional reconstruction of the anatomical tissue, and through the use of contrast agents it is also possible to identify tumors in the early stage of their development, thus leading to more effective treatments. Our commitment is towards the optimization of these techniques, so as to provide radiological imaging with the best tools for diagnosis and prevention.

In particular, our research group has been involved in scientific projects concerning the advanced applications of digital mammography such as dual-energy and tomosynthesis, also in cooperation with women's healthcare companies for their technology transfer.

Finally, the medical use of ionizing radiation represents the main contribution to the radiation dose among the population of the European Union. Training of the Medical Physics Expert is one of the EU strategies to contain this risk, and our team is a member of the European network EUTEMPE to address this important educational task.


Selected publications:


 

Innovative X-ray sources

In the field of X-ray imaging, the radiation source plays a fundamental role. To improve image quality, while simultaneously decreasing the delivered radiation dose, it is important to develop innovative sources of monochromatic X radiation. Monochromatic sources, unlike traditional sources such as X-ray tubes, emit radiation of a single energy. Over the years the group has been involved in various projects with this goal, both national and European, such as SL-Thomson@INFN-LNF, Labsynch, Eurogammas@ELI-NP, and recently MariX/BriXsino .

In the last few years, the main interest has been focused on the realization of inverse Compton sources for medical applications. Inverse Compton sources are based on the interaction between accelerated electrons and intense laser beams. 

Our research group is mainly involved with the study, simulation and measurement of the characteristics of the emitted radiation and development of innovative techniques, in order to optimize the results of diagnostic imaging.

Selected publications:

Photon-counting X-ray imaging detectors

Nowadays many detector technologies are available for X-ray digital imaging. The vast majority of those used in the clinical practice have in common the same operating principle: the signal collected is the result of the integration of the total energy released by the irradiation in the active volume of each pixel. No information is acquired regarding the number of photon interacting or their energy distribution (spectrum). 

Instead, photon counting detectors with spectroscopic capabilities allow instead to count the quanta interacting and obtain an information about the energy of each photon. This technology can be used to eliminate electronic noise, increase spatial resolution and take advantage of the spectral information to improve the diagnostic power, resulting in a lower radiation dose and enabling the implementation of advanced imaging techniques, such as tissue discrimination.

Our group is involved in the  INFN Medipix4 project, which  is aimed at the development and application of the integrated circuits (ASICs) developed by the Medipix4 Collaboration at CERN, which will allow to develop detectors with performances far beyond the state-of-the-art. 


X-ray microtomography

X-ray microtomography (XMT) is a non-destructive evaluation technique that allows the internal structure of an object to be imaged by reconstructing the spatial distribution of the local linear X-ray absorption coefficients of the materials/phases contained within. This provides a virtual 3D representation of the internal architecture of an object from which two-dimensional (2D) cross-sectional slices can be extracted along the three orthogonal planes of an object. The 3D object can be converted into a microstructurally faithful 3D mesh suitable for Finite Element Modelling that can describe the geometry of each constituent.

Micro-CT has applications both in medical imaging and in industrial computed tomography. In general, there are two types of scanner setups. In one setup, the X-ray source and detector are typically stationary during the scan while the sample/animal rotates. The second setup, much more like a clinical CT scanner, is gantry based where the animal/specimen is stationary in space while the X-ray tube and detector rotate around. These scanners are typically used for small animals (in-vivo scanners), biomedical samples, foods, microfossils, and other studies for which minute detail is desired.

Selected publications:

Cerebral Venous Return

The aim of this research topic is to characterize the human cardiovascular function by developing advanced non-invasive protocols easily usable in clinic and research, in co-operation with the Vascular Diseases Centre of the University of Ferrara. Such activity is based on the fruitful results of the Drain Brain project, sponsored by the Italian Space Agency (ASI) and successfully conducted by our group aboard the International Space Station , where the circulatory system functionality of a crewmember was assessed.

In the framework of the project WISE - Wearable non-Invasive SEnsors for cardiovascular function assessment , funded by the INFN, we have been involved in the development of an open ultrasound and plethysmography system so as to integrate the recorded traces with current standardized measurements (e.g. electrocardiography). Moreover, we are developing mathematical models for the simulation of human blood flows and pressures. In cooperation with the CRIBO Training Academy we are also developing ad-hoc phantoms, so as to perform in-vitro measurements of diagnostic interest.

Finally, the UNIFE team has been recently selected by ASI for another experiment on the ISS, namely the Drain Brain 2.0 project for the "Assessment of the cerebral venous outflow in a microgravity environment through the detection of jugular venous pulse oscillations". 

Selected publication:

Monte Carlo simulation and modelling

Monte Carlo (MC) simulations play an important role in a variety of situations in medical physics. In particular, MC codes that simulate the interactions of particles with matter can be exploited to predict the outcome of an experiment or to refine the design of a component of the experimental setup. The effect of changing a system parameter can be studied without the need of a real irradiation of the sample/patient, which can be prevented due to dosimetric issues or simply because the radiation source under investigation is not yet available.

The Medical physics group is involved in various MC studies, spanning from those related to new source of radiation, such as inverse Compton sources, to those that aim to model the response of a detector. The studies are carried out through Geant4, which is a C++-based open-source particle tracking code, among the more complete and powerful. 

In order to increase the field of application and make the simulations closer to reality, the physical models have to be refined and extended. An important research area of the group is the development of new models of the coherent interactions of X-rays with matter and their implementation in Geant4. Among the considered phenomena there are the inclusion of interference effects in Rayleigh scattering of X-rays in both amorphous and crystalline materials and the X-ray refraction/reflection at the interface between two different materials. These extensions open the way to inclusion of phase effects in Geant4, which can then be used to simulate phase-contrast imaging.

Selected recent publications on the topic:

Geant4

At this page, useful Geant4 applications can be found.

AI in medical imaging

The group is currently involved in the next_AIM project devoted to investigate the potential of Artificial Intelligence (AI) techniques in medical applications.  

The main field of study of the Ferrara group concerns X-ray imaging of the breast. In particular, we are involved in the development of a tool for decision support in Digital Breast Tomosynthesis (DBT) exams. From suitably pre-processed DBT slices it is possible to extract radiomic features useful for identifying any lesions using a Machine Learning algorithm. This classification can be combined with that provided by a Convolutional Neural Network (CNN), i.e. by a dedicated Deep Learning tool, to obtain a more accurate prediction of the potential presence of lesions in each slice and possibly their location.  

A further field of investigation concerns the applications of AI in cardiology. In particular, the automatic analysis of plethysmographic traces, i.e. Jugular Venous Pulse (JVP) curves measured using a strain gauge applied to the neck. These curves can in fact in turn be correlated with the hemodynamic activity of the heart. An additional goal is the automatic segmentation of jugular veins and carotids from ultrasound images and then derive both JVP curves and atrial distension waveforms.