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By means of a combined microscopy-, spectroscopy-, and tomography-based approach, we investigated surface and interface defects in metal-polymer heterostacks. The aim was to characterize both morphological and compositional alterations of the surfaces, originating in the physical vapor deposition (PVD) growth methods adopted in the fabrication process. Synchrotron radiation X-ray computed tomography (CT) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray Spectroscopy (EDS) indicate that both chemical contaminations, introduced in the fabrication process, and growth conditions strongly affect the presence of defects. On the basis of our results, we classified the defects into four main families. Interestingly, the faults are mainly located at the metal-polymer interface. Thanks to this study, we have been able to gain a deeper insight into the defects' origins and nature, allowing the identification of the precise production steps involved in the generation of the selected defects.

In the case of single-distance propagation-based phase-contrast X-ray computed tomography with synchrotron radiation, the conventional reconstruction pipeline includes an independent 2D phase retrieval filtering of each acquired projection prior to the actual reconstruction. In order to compensate for the limited height of the X-ray beam or the small sensitive area of most modern X-ray photon-counting detectors, it is quite common to image large objects with a multi-stage approach, i.e. several acquisitions at different vertical positions of the sample. In this context, the conventional reconstruction pipeline may introduce artifacts at the margins of each vertical stage. This article presents a modified computational protocol where a post-reconstruction 3D volume phase retrieval is applied. By comparing the conventional 2D and the proposed 3D reconstructions of a large mastectomy specimen (9 cm in diameter and 3 cm in height), it is here shown that the 3D approach compensates for the multi-stage artifacts, it avoids refined projection stitching, and the image quality in terms of spatial resolution, contrast and contrast-to-noise ratio is preserved.

Item does not contain fulltext Breast computed tomography (BCT) is an emerging application of X-ray tomography in radiological practice. A few clinical prototypes are under evaluation in hospitals and new systems are under development aiming at improving spatial and contrast resolution and reducing delivered dose. At the same time, synchrotron-radiation phase-contrast mammography has been demonstrated to offer substantial advantages when compared with conventional mammography. At Elettra, the Italian synchrotron radiation facility, a clinical program of phase-contrast BCT based on the free-space propagation approach is under development. In this paper, full-volume breast samples imaged with a beam energy of 32 keV delivering a mean glandular dose of 5 mGy are presented. The whole acquisition setup mimics a clinical study in order to evaluate its feasibility in terms of acquisition time and image quality. Acquisitions are performed using a high-resolution CdTe photon-counting detector and the projection data are processed via a phase-retrieval algorithm. Tomographic reconstructions are compared with conventional mammographic images acquired prior to surgery and with histologic examinations. Results indicate that BCT with monochromatic beam and free-space propagation phase-contrast imaging provide relevant three-dimensional insights of breast morphology at clinically acceptable doses and scan times.

Purpose We propose a technique for the characterization of tissues, based on a hybrid phase contrast-attenuation imaging. The technique, first introduced in [1] , makes use of a method for material basis decomposition proposed by Alvarez and Macovski [2] . We present a semi-analytical simulation of the imaging process, as well as a preliminary implementation on a set of radiographic images of a dedicated phantom. Methods The phantom consists in a thin plastic plate composed of two “soft” materials, arranged in such a way to create a faint pattern of decreasing radiographic contrasts. The imaging was performed using synchrotron radiation (i.e. a quasi-parallel, monochromatic and coherent X-ray beam) and placing the phantom at different distances from the detector, so as to enhance the contribution of phase contrast. The images were acquired at the SYRMEP beamline of the Elettra synchrotron facility (Trieste, Italy). Results The reconstructed composition of the phantom was compared to the results of the semi-analytical simulation, showing a good agreement with the theoretical expectations. In particular, the technique proved able to enhance the visibility of faint contrasts with respect to the standard attenuation-based imaging. Moreover, it provided a precise quantitative estimate of the local composition of the imaged phantom. Conclusions The application of the basis decomposition method to the context of phase contrast imaging allows an effective rendering of a broad spectrum of radiographic patterns, from low frequency textures (which are captured by the attenuation effects) to high frequency details (highlighted by the phase shift effects). In addition, thanks to the simultaneous enforcement of two separate imaging channels, it also allows a two-component reconstruction of the imaged object.

Purpose There is a worldwide shortage of clinical medical physics professionals and medical physics academics. Adequate academic education and structured clinical training of medical physicists play a vital role in ensuring the safe and effective use of advanced technologies in both diagnosis and treatment. In order to address the problem of supporting high-level skills in countries without post-graduate education in Medical Physics an international Master of Advanced Studies in Medical Physics has been jointly organized by our institutions. Methods The Master offers a study program in line with the best international practices that provides both knowledge and practical skills to graduate students. It is a two-years program: one academic year of theoretical classes followed by one year of supervised clinical training in radiotherapy or medical imaging. The clinical training is organized according to the IAEA, AFRA and IOMP guidelines. It is jointly organized by the Physics Department of the local university, and by an international scientific institution located in the same area. The university hospital actively supports the program. Most fellowships are provided by an international agency, and are supplemented by others from local or international institutions. Results The 5th cycle of the Master was opened in 2018. Up to now 86 students have been enrolled in the Master from all the continents: 39 from Africa, 21 from Asia, 19 from Latin America, 1 from Oceania and 6 from Europe (25 women and 61 men). The cooperation between university and the international scientific institution is a recognized example of effective synergy: the university has experience in high-level education and organization of courses while the international institution has an efficient network for the international enrolment of students and a large experience in international mobility. The generous collaboration of a large number of hospitals with medical physics departments guarantees a one-year-long supervised clinical training per each student. Conclusions The Master programme requires an extensive effort from both students and the organizing institutions, but the results are very satisfactory as the graduates are highly appreciated in the hospitals in their home countries.

Purpose PCDs with energy discrimination led to new possibilities of improving the quality of X-ray medical images. PCDs are direct detection devices in which the charge delivered by a single interacting photon is directly collected and discriminated at single pixels level. The limit of high densely pixelated PCDs is the charge sharing which can lead to multiple counts from a single interaction degrading the spatial resolution of the system. Increasing the discrimination threshold, multiple counts can be partially or totally removed from images improving the spatial resolution at the cost of a reduction of the detection area of single pixels with a consequent loss of statistics. This work aims to show a simple method to find the optimal threshold which gives the best trade-off between spatial resolution and statistics. Methods The acquisitions have been performed at the SYRMEP beamline (Elettra Trieste) using the tomographic experimental set-up of INFN project SYnchrotron Radiation MAmmography (SYRMA-3D). SYRMA-3D uses ‘Pixirad-8’, a PCD with CdTe sensor and a pixel size of 60 μm. For this study, we used a monochromatic beam of 38 keV acquiring a set of images of an edge and a set of images of the beam with different detection thresholds. The two sets of images have been used respectively for the measurement of the Modulation transfer function (MTF) and the noise power spectrum (NPS). Combining both NPS and MTF the Number of Equivalent Quanta (NEQ) can be determined. The NEQ summarizes both informations about spatial resolution and noise and is an useful metrics for the global image quality assessment. Results The comparison between NEQ curves shows that lower thresholds give better NEQ response. Conclusions The increase of the discrimination threshold improves the spatial resolution but worsens the noise. The global image quality, measured using NEQ, is higher for lower thresholds.

Purpose To measure the dose distribution in a phantom during a synchrotron radiation (SR) computed tomography (CT) scan using radiochromic films, for procedure assessment and for offline dose monitoring in SR breast CT. Methods We used XR-QA2 radiochromic films (calibrated in terms of free air kerma) and a 14-cm PMMA cylindrical phantom. Measurements were performed at the SYRMEP beamline of ELETTRA facility, within the SYRMA-3D project for phase-contrast breast CT [1] . The phantom was positioned at isocenter, pending from the patient bed. Measurements were performed at 38 keV, beam size of 3 mm × 150 mm (H × W), at an air kerma corresponding to a mean glandular dose of 5 mGy in a 14-cm diameter 50% glandular breast. The phantom was irradiated over 360° first with a film at the mid-plane, and then with film strips wrapped on its surface. Additional tests were made over 180° with an axial scan pitch of 1, 0.8 or 0.5. Results Results show a dose map at mid-plane the phantom, indicating the cup-shaped horizontal profile due to primary and scatter dose. Analogous maps were recorded with the films at the periphery of the phantom, representing the surface dose maps. Conclusions We performed measurements of the dose distribution in a phantom during a SR CT scan with different irradiation geometries. This technique produces evidence for selecting the suitable scan procedure. Moreover, as an offline monitor system, a piece of calibrated radiochromic film wrapped on a suitable holder around the breast could record the history of the organ irradiation.

Purpose Breast Computed Tomography (CT) is a dedicated 3D imaging modality that provides a complete volumetric reconstruction of the uncompressed organ, thus matching a high image quality with an acceptable delivered dose. The SYRMA-3D collaboration is developing the first clinical trial of phase-contrast breast CT with synchrotron radiation at the Elettra synchrotron facility in Trieste. We present a proposal for a Quality Control (QC) protocol, including a custom made QC phantom that was designed and built by the laboratories of the University of Ferrara. Methods The synchrotron beam is monochromatic in the energy range 8.5–40 keV. The images were acquired with a photon counting detector placed at about 2 m from the organ, so as to generate a phase contrast signal. The QC phantom consists of a water filled PMMA cylinder, hung from the patient support through the breast aperture. It contains several inserts that allow measurements of geometric alignment, reconstruction uniformity and linearity, low and high contrast resolution. Results CT images of the phantom were acquired at several beam energies within the range of interest, to explore the energy dependence of the results. Uniformity and linearity appeared to be preserved by the reconstruction for all energies. Conversely, low contrast details exhibited a more pronounced dependence on the energy choice. Finally, the visibility of high contrast details was always found above acceptance levels. Conclusions The main goal of the study was to verify the compatibility of the QC phantom with the experimental environment of the SYRMA-3D project, and to test the validity and feasibility of the proposed QC protocol. With minimal modifications, they proved viable instruments to perform the necessary quality assessments for the innovative diagnostic device developed by the SYRMA-3D collaboration.

Purpose: In the past decade, phase-contrast imaging (PCI) has been applied to study different kinds of tissues and human body parts, with an increased improvement of the image quality with respect to simple absorption radiography. A technique closely related to PCI is phase-retrieval imaging (PRI). Indeed, PCI is an imaging modality thought to enhance the total contrast of the images through the phase shift introduced by the object (human body part); PRI is a mathematical technique to extract the quantitative phase-shift map from PCI. A new phase-retrieval algorithm for the in-line phase-contrast x-ray imaging is here proposed. Methods: The proposed algorithm is based on a mixed transfer-function and transport-of-intensity approach (MA) and it requires, at most, an initial approximate estimate of the average phase shift introduced by the object as prior knowledge. The accuracy in the initial estimate determines the convergence speed of the algorithm. The proposed algorithm retrieves both the object phase and its complex conjugate in a combined MA (CMA). Results: Although slightly less computationally effective with respect to other mixed-approach algorithms, as two phases have to be retrieved, the results obtained by the CMA on simulated data have shown that the obtained reconstructed phase maps are characterized by particularly low normalized mean square errors. The authors have also tested the CMA on noisy experimental phase-contrast data obtained by a suitable weakly absorbing sample consisting of a grid of submillimetric nylon fibers as well as on a strongly absorbing object made of a 0.03 mm thick lead x-ray resolution star pattern. The CMA has shown a good efficiency in recovering phase information, also in presence of noisy data, characterized by peak-to-peak signal-to-noise ratios down to a few dBs, showing the possibility to enhance with phase radiography the signal-to-noise ratio for features in the submillimetric scale with respect to the attenuation-based imaging. Conclusions: It has been shown that phase-retrieved radiographies can be used both to have quantitative phase information about soft tissues, complementary to the attenuation information, and to enhance the visibility of details inside soft tissues, with higher efficiency with respect to phase radiography.

In this work, we intend to relate the mineral to non-mineral bone scattering intensity ratio with the bone-mineral density (BMD) reduction. In this way, EDXRD can be a novel technique to measure BMD loss in function of the mineral and non-mineral scattering intensity. The scattering profiles were obtained at Laboratorio Nacional de Luz Sincrotron (LNLS) at the X-ray diffraction beamline XD2. A double-crystal Si(1 1 1) pre-monochromator, upstream of the beamline, was used to select a small energy bandwidth (Δ λ / λ ≈10 −4 ) at 11 keV. The sample holder has a circle depression in the center to contain a range of bone and fat mixture ratios. The mixture consists of powdered cortical bone and fat, which together simulate in vivo bone. The diffraction patterns were carried out with 0.5 mm slits after and behind of the sample holder. The data were collected in 0.05° increments every 0.5 s. EDXRD results show an indication of different bone densities may be distinguished which suggested that X-ray coherent scattering technique may have a role in monitoring changes in BMD via changes in the related scattering intensity of mineral and non-mineral bone. The main aim of the Synchrotron Radiation for MEdical Physics (SYRMEP) project at the ELETTRA is the investigation and the development of innovative techniques for medical imaging. The beamline provides, at a distance of about 23 m from the source, a monochromatic, laminar section X-ray beam with a maximum area of about 160×5 mm 2 at 20 keV. The monochromator, that covers the entire angular acceptance of the beamline, is based on a double-Si (1 1 1) crystal system working in Bragg configuration. A micrometric vertical and horizontal translation stage allows the positioning and scanning of the sample with respect to the stationary beam. In this case, the detector is kept stationary in front of the beam, while the object is rotated in discrete steps in front of it. At each rotation, a projection is acquired. A goniometric double-cradle system is used to adjust the rotation axis, which must be orthogonal with respect to the detector plane in transmission computed tomography (CT). The samples consisted of a 8 mm cube of bovine bone surrounded of a cartilage interface. High-resolution images of the trabecular structure were obtained by means a 16-bit CCD camera, 2048×2048 pixels, 14 μm pixel size (maximum spatial resolution: 25 μm).

A theoretical analysis of the x-ray phase contrast imaging and its validation via synchrotron radiation imaging is here presented. Two different mathematical models have been followed: the simpler ray-optical approach and the more rigorous Fresnel-Kirchoff diffraction theory. Subsequently, the conditions upon which the x-ray optical approximation can be used to describe the image formation mechanism have been analyzed, taking into account also the effects due to the finite source size and detector resolution. It is possible to demonstrate that the ray-optics results can also be obtained by opportunely developing the diffraction formalism only with some restrictions on the spatial frequencies present in the final image, without any limitation on the maximum phase shift. The conditions allowing the use of the simplified ray-optical approach to describe the phase contrast images have been here defined and their validation has been proved by means of computer simulations and phantom experiments.

The goal of this project is to determine the feasibility of utilizing colloidal gold as a marker for C6 glioblastoma cells implanted into rat brain as an appropriate model for volumetric measurements of tumors using absorption edge subtraction (AES). Phase sensitive X-ray imaging is combined with KES to give good soft tissue contrast. Current methods for volumetric measurements of implanted C6 glioblastoma tumors in rat brains using MRI technology are inadequate due to the small size of the tumor (2.5–4 mm in diameter) and the thickness of the MRI slice (1–1.5 mm). Previously, our group has shown that AES detection of colloidal gold labeled C6 glioblastoma cells implanted into a rat brains may be feasible. The long-term goal for this project is to establish a method, which would allow the researcher to monitor the development of a tumor over time. Most importantly, this technique should allow researchers to accurately determine the potency of a treatment on the size and growth rate for a C6 implanted tumors. In addition, we plan to challenge the hypothesis that tumors of the glioma type do not metastasize outside of the brain. A sensitive technique for the detection of C6 cells, such as that using colloidal gold and AES/DEI, should enable researchers to detect C6 cells, which have metastasized and migrated to different areas of the body. The ability to detect implanted C6 cells followed by the development of the tumor, the possible migration of the cells and the ability to accurately measure the effects of treatments on the volume of the tumor would be of the utmost importance to brain tumor research.

Enhanced contrast X-ray imaging is achieved by exploiting the real part ofthe refraction index, which is responsible for the phase shifts, in addition to the imaginary part, which is responsible for the absorption. Such techniques are called X-ray phase contrast imaging. An analyzer-based X-ray phase contrast imaging set-up with Diffraction Enhanced Imaging processing (DEI) were used for preliminary studies in anatomy and embryology of insects. Parasitized stinkbug and moth eggs used as control agents ofpests in vegetables and adult stinkbugs and mosquitoes (Aedes aegypti) were used as samples. The experimental setup was mounted in the SYRMEP beamline at ELETTRA. Images were obtained using a high spatial resolution CCD detector (pixel size 14 � 14mm 2 ) coupled with magnifying optics. Analyzer-based X-ray phase contrast images (PCI) and edge detection images show contrast and details not observed with conventional synchrotron radiography and open the possibility for future study in the embryonic development ofinsects. r 2005 Elsevier B.V. All rights reserved.

Conventional X-ray medical imaging makes use of the transmission properties of the sample. On the other hand, recently introduced phase-sensitive techniques take advantage of the phase shifts that occur when an electromagnetic wave encounters different refraction indices. Diffraction-Enhanced Imaging (DEI) is a phase-sensitive X-ray imaging technique based on the use of an analyzer placed between the sample and the detector. DEI performed at several synchrotron radiation facilities worldwide has proven outstanding image quality both in material science and medical imaging. At the medical imaging beamline SYRMEP under operation at the synchrotron radiation facility ELETTRA (Trieste, Italy), an analyzer system has been implemented to perform DEI. Experiments to evaluate the associated improvements in image quality were carried out on phantoms and biological samples and to prove that DEI is an appropriate tool for studying refraction and scattering properties. The results observed on the examples reported in this work suggest that the edge-enhancement effects and the superior sensitivity to soft tissue make DEI a valuable tool for early diagnosis of subtle diseases in many different fields.

Glioblastoma multiforme (GBM) is the commonest and most aggressive primary brain tumor in humans. The high rate of tumor recurrence results in a poor prognosis despite multimodality treatment. One reason for high rate of recurrence is the invasive nature of the tumor into the surrounding normal brain tissue or multifocal occurrence at sites remote from that of the primary tumor establishment. Existing imaging demonstrates the primary tumor but fail to show the residual tumor microaggregates left behind following initial treatment. In this study, we employed diffraction-enhanced imaging (DEI) in an attempt to find an imaging modality that will provide visualization of residual disease that is not be apparent on MRI or CT scans.

This report discusses the optimization strategy, the theoretical background and first experimental data of a new refractive lens for focusing X-rays. In order to reduce the absorption of X-rays in this transmission lens, optically passive material was removed from the necessarily concave lens shape in a highly regular pattern. The feature dimensions require lens production and replication by deep X-ray lithography, which allows shaping in only one dimension. Consequently such a lens can focus in one direction only, so a crossed lens pair is needed for two-dimensional focusing. The single lens is composed of two large prisms of millimetre size, which touch each other at one of the tips, like an old sand clock. Each large prism contains a highly regular structure of essentially identical prism-like smaller segments. The first lens prototypes focused an X-ray beam with a vertical size of 500 microm and a photon energy of 8 keV to a line with a width of only 2.8 microm. This is only slightly worse than the line width of 1.73 microm expected for its focal length of f = 2.18 m. The photon density enhancement in the focus was 25, but could have been larger as the lens can intercept a beam height of 2.6 mm.

Recently, new imaging modalities based on the detection of weak phase perturbations effects, among which are phase contrast and diffraction imaging, have been developed by several researchers. Due to their high sensitivity to weakly absorbing details, these techniques seem to be very promising for applications in the medical field. On the other hand, digital radiology is undergoing a wide diffusion, and its benefits are presently very well understood. Up to now, however, the strong pixel size constraints associated with phase contrast pattern detection limited the possibility of exploiting the advantages of phase contrast in digital radiology applications. In this paper, an innovative setup capable of removing the pixel size constraints, and thus opening the way to low dose digital phase contrast imaging, is described. Furthermore, we introduce an imaging technique based on the detection of radiation scattered at small angles: the information extracted from the sample is increased at no dose expense. We believe that several radiological fields, mammography being the first important example, may benefit from the herein described innovative imaging techniques.

The SYRMEP beam line is currently in the upgrading phase for mammographic examinations on patients at Elettra in Trieste. At the same time, a digital detection system, suitable for in -vivo breast imaging, is under development; it consists of a silicon laminar detector array operating in single photon counting mode. The duration of a clinical examination should not exceed a few seconds. Fast read out electronics is therefore necessary with the aim of avoiding losses in image contrast in presence of high counting rates. A custom ASIC working with 100% efficiency for rates up to 100 kHz per pixel has been designed and tested, and other solutions based on commercially available ASICs are currently under test. Several detector prototypes have been assembled, and images of mammographic test objects have been acquired. Image quality, efficiency and contrast losses have been evaluated in all cases as a function of the counting rate.

Introduction Iterative tomographic reconstruction techniques are particularly interesting when the number of acquired projections is not enough to match the Nyquist criteria. These techniques differ in computational time and image quality. Purpose SIRT, SART and CGLS algorithms have been studied in order to evaluate the application of iterative reconstruction methods to low-dose phase-contrast breast tomography, in the framework of the SYRMA-CT project. The number of iterations has been optimized while reducing the number of projections used during the reconstruction. Materials and methods The tomographic data set of two large breast tissue samples (9 cm) has been acquired using a monochromatic X-ray beam at 38 keV. Images were acquired in propagation-based phase-contrast mode and a single-material single-distance phase-retrieval algorithm was applied to the projections before reconstruction. The codes applied are part of the ASTRA Tomography Toolbox. The quality of the images was evaluated using the CNR and few full-reference quality indexes. The reconstruction performed with the filter back-projection including all the acquired projections was considered as gold standard. Results According to full-reference indexes the best quality is achieved when the CNR is similar to the one of the gold standard. The number of iterations can be used to optimize the noise preserving the visibility of the details. Conclusion Full reference indexes require a gold standard acquired at higher statistics, due to their strong dependence on the noise. The evaluation of a team of radiologists is required to compare full-references quality indexes and diagnostic quality of the reconstructed images. Disclosure Nothing to declare.

In the past decade, phase-contrast imaging (PCI) has been applied to study different kinds of tissues and human body parts, with an increased improvement of the image quality with respect to simple absorption radiography. A technique closely related to PCI is phase-retrieval imaging (PRI). Indeed, PCI is an imaging modality thought to enhance the total contrast of the images through the phase shift introduced by the object (human body part); PRI is a mathematical technique to extract the quantitative phase-shift map from PCI. A new phase-retrieval algorithm for the in-line phase-contrast x-ray imaging is here proposed.The proposed algorithm is based on a mixed transfer-function and transport-of-intensity approach (MA) and it requires, at most, an initial approximate estimate of the average phase shift introduced by the object as prior knowledge. The accuracy in the initial estimate determines the convergence speed of the algorithm. The proposed algorithm retrieves both the object phase and its complex conjugate in a combined MA (CMA).Although slightly less computationally effective with respect to other mixed-approach algorithms, as two phases have to be retrieved, the results obtained by the CMA on simulated data have shown that the obtained reconstructed phase maps are characterized by particularly low normalized mean square errors. The authors have also tested the CMA on noisy experimental phase-contrast data obtained by a suitable weakly absorbing sample consisting of a grid of submillimetric nylon fibers as well as on a strongly absorbing object made of a 0.03 mm thick lead x-ray resolution star pattern. The CMA has shown a good efficiency in recovering phase information, also in presence of noisy data, characterized by peak-to-peak signal-to-noise ratios down to a few dBs, showing the possibility to enhance with phase radiography the signal-to-noise ratio for features in the submillimetric scale with respect to the attenuation-based imaging.It has been shown that phase-retrieved radiographies can be used both to have quantitative phase information about soft tissues, complementary to the attenuation information, and to enhance the visibility of details inside soft tissues, with higher efficiency with respect to phase radiography.

We derive a Fourier formulation of coded-aperture x-ray phase-contrast imaging, based on the wave theory of optics in the Fresnel approximation. We use this model to develop a flexible, efficient, and general simulation algorithm that can be easily adapted to other implementations of x-ray phase contrast imaging. Likewise, the algorithm enables a simple extension to 2D aperture designs, different acquisition schemes, etc. Problems related to numerical implementation of the algorithm are analyzed in detail, and simple rules are derived that enable us to avoid or at least mitigate them. Finally, comparisons with experimental data and data obtained with a different simulation algorithm are presented to validate the model and demonstrate its advantages in practical implementations. This also enabled us to demonstrate an increase in computational speed of more than one order of magnitude over a previous algorithm. (C) 2013 Optical Society of America

The use of microbubbles as a contrast agent for x-ray phase contrast imaging could both transform x-ray imaging into a “functional” modality and enable much needed monitoring of targeted drug delivery. To realize these benefits, it is essential to be able to quantify bubble concentration in a given tissue volume. We developed and validated a model that enables this to be achieved not only for phase-retrieved images obtained by processing multiple frames but also on “single-shot” images, a likely necessity in in-vivo implementations. Our experimental validation was based on analyzer-based imaging, but extension to other phase-based modalities is straightforward.