scholarly journals The potential of utilizing mid-energy X-rays for in-line phase sensitive breast cancer imaging

2020 ◽  
Vol 9 (3-4) ◽  
pp. 89-102
Author(s):  
F.H. Omoumi ◽  
M.U. Ghani ◽  
M.D. Wong ◽  
Y. Li ◽  
B. Zheng ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Phase Contrast ◽  
Low Dose ◽  
Imaging System ◽  
Energy System ◽  
High Energy ◽  
Imaging Systems ◽  
X Rays ◽  
Breast Cancer Imaging ◽  
Phase Sensitive

OBJECTIVE: The objective of this phantom study is to demonstrate the potential of utilizing mid-energy x-rays for in-line phase-sensitive breast cancer imaging by phantom studies. METHODS: The midenergy (50–80 kV) in-line phase sensitive imaging prototype was used to acquire images of the contrast-detail mammography (CDMAM) phantom, an ACR accreditation phantom, and an acrylic edge phantom. The low-dose mid-energy phase-sensitive images were acquired at 60 kV with a radiation dose of 0.9 mGy, while the high-energy phase-sensitive images were acquired at 90 kV with a radiation dose of 1.2 mGy. The Phase-Attenuation Duality (PAD) principle for soft tissue was used for the phase retrieval. A blind observer study was conducted and paired-sample T-test were performed to compare the mean differences in the two imaging systems. RESULTS: The correct detection ratio for the CDMAM phantom for phase-contrast images acquired by the low-dose mid-energy system was 56.91%, whereas images acquired by the high-energy system correctly revealed only 40.97% of discs. The correct detection ratios were 57.88% and 43.41% for phase-retrieved images acquired by the low-dose mid-energy and high-energy imaging systems, respectively. The reading scores for all three groups of objects in the ACR phantom were higher for the mid energy imaging system as compared to the high-energy system for both phase-contrast and phase-retrieved images. The calculated edge enhancement index (EEI) from the acrylic edge phantom image for the mid-energy system was higher than that calculated for the high-energy imaging system. The quantitative analyses showed a higher Contrast to Noise Ratio (CNR) as well as a higher Figure of Merit (FOM) in images acquired by the low-dose mid-energy imaging system. CONCLUSION: The PAD based retrieval method can be applied in mid-energy system without remarkably affecting the image quality, and in fact, it improves the lesion detectability with a patient dose saving of 25%.

Evaluation and comparison of a CdTe based photon counting detector with an energy integrating detector for X-ray phase sensitive imaging of breast cancer

2021 ◽  
pp. 1-13
Author(s):  
Muhammad U. Ghani ◽  
Farid H. Omoumi ◽  
Xizeng Wu ◽  
Laurie L. Fajardo ◽  
Bin Zheng ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Spatial Resolution ◽  
Standard Dose ◽  
Photon Counting ◽  
High Energy ◽  
Edge Enhancement ◽  
X Ray ◽  
Photon Counting Detector ◽  
Phase Sensitive ◽  
Observer Studies

PURPOSE: To compare imaging performance of a cadmium telluride (CdTe) based photon counting detector (PCD) with a CMOS based energy integrating detector (EID) for potential phase sensitive imaging of breast cancer. METHODS: A high energy inline phase sensitive imaging prototype consisting of a microfocus X-ray source with geometric magnification of 2 was employed. The pixel pitch of the PCD was 55μm, while 50μm for EID. The spatial resolution was quantitatively and qualitatively assessed through modulation transfer function (MTF) and bar pattern images. The edge enhancement visibility was assessed by measuring edge enhancement index (EEI) using the acrylic edge acquired images. A contrast detail (CD) phantom was utilized to compare detectability of simulated tumors, while an American College of Radiology (ACR) accredited phantom for mammography was used to compare detection of simulated calcification clusters. A custom-built phantom was employed to compare detection of fibrous structures. The PCD images were acquired at equal, and 30% less mean glandular dose (MGD) levels as of EID images. Observer studies along with contrast to noise ratio (CNR) and signal to noise ratio (SNR) analyses were performed for comparison of two detection systems. RESULTS: MTF curves and bar pattern images revealed an improvement of about 40% in the cutoff resolution with the PCD. The excellent spatial resolution offered by PCD system complemented superior detection of the diffraction fringes at boundaries of the acrylic edge and resulted in an EEI value of 3.64 as compared to 1.44 produced with EID image. At MGD levels (standard dose), observer studies along with CNR and SNR analyses revealed a substantial improvement of PCD acquired images in detection of simulated tumors, calcification clusters, and fibrous structures. At 30% less MGD, PCD images preserved image quality to yield equivalent (slightly better) detection as compared to the standard dose EID images. CONCLUSION: CdTe-based PCDs are technically feasible to image breast abnormalities (low/high contrast structures) at low radiation dose levels using the high energy inline phase sensitive imaging technique.

Investigation of Fatigue Crack Propagation in Nickel Superalloy Using Diffraction Contrast Tomography and Phase Contrast Tomography

2014 ◽  
Vol 891-892 ◽  
pp. 923-928 ◽  
Author(s):  
Olivier M.D.M. Messé ◽  
Joel Lachambre ◽  
Andrew King ◽  
Jean Yves Buffière ◽  
Cathie M.F. Rae
Keyword(s):  
Fatigue Crack ◽  
Crack Propagation ◽  
Fatigue Crack Propagation ◽  
Phase Contrast ◽  
High Energy ◽  
Short Crack ◽  
X Rays ◽  
Post Mortem ◽  
Diffraction Contrast ◽  
Phase Contrast Tomography

Evaluation of superalloy component life in turbine engines requires a detailed understanding of how fatigue crack initiation and short crack propagation contribute to fatigue life. However most investigations have been carried out post-mortem and in two dimensions. New techniques are able to fully resolve cracks propagating in four dimensions (space and time), enabling characterisation of their local environments and allowing a much deeper understanding of fatigue mechanics. Nickel-based superalloys experiencing high cycle fatigue have shown a high sensitivity to microstructure during initiation and short crack propagation. Using high energy X-rays and the combination of Diffraction Contrast Tomography (DCT) and Phase Contrast Tomography (PCT), we followed a fatigue crack initiated from a Focused Ion Beam (FIB) milled notch at room temperature. Analyses have been carried out to fully characterise the crack and its environment. We tracked the evolution of the crack and interactions with the microstructure. Subsequently, post-mortem investigations have been carried out to corroborate results obtained from the tomographs and to provide more local information of fatigue crack propagation.

scholarly journals A method for high-energy, low-dose mammography using edge illumination x-ray phase-contrast imaging

2016 ◽  
Vol 61 (24) ◽  
pp. 8750-8761 ◽  
Author(s):  
Paul C Diemoz ◽  
Alberto Bravin ◽  
Anikó Sztrókay-Gaul ◽  
Marie Ruat ◽  
Susanne Grandl ◽  
...  
Keyword(s):  
Phase Contrast ◽  
Low Dose ◽  
High Energy ◽  
Phase Contrast Imaging ◽  
Contrast Imaging ◽  
X Ray

Development of Real Time High Energy X-Ray Imaging System for Use in Dynamic Fluoroscopy of Aero Gas Turbines

1975 ◽  
Author(s):  
A. E. Stewart
Keyword(s):  
Real Time ◽  
Gas Turbines ◽  
Imaging System ◽  
High Energy ◽  
Cesium Iodide ◽  
Imaging Systems ◽  
X Ray ◽  
X Ray Imaging ◽  
Different Types

This paper discusses the development of a real-time high energy x-ray imaging system for use in dynamic fluoroscopy of aero gas turbines. In order to cover the range of subjects on gas turbines, over ten combinations of film and screen types are used. Three different types of x-ray imaging systems were considered for use: direct type intensifiers (cesium iodide phosphors), and indirect type intensifiers — Marconi “Marionette” and the Oude Delft “Delcalix.”

In-line holography and phase-contrast microtomography with high energy x-rays

1999 ◽  
Vol 44 (3) ◽  
pp. 741-749 ◽  
Author(s):  
P Spanne ◽  
C Raven ◽  
I Snigireva ◽  
A Snigirev
Keyword(s):  
Phase Contrast ◽  
High Energy ◽  
X Rays

scholarly journals Low-dose X-ray structure analysis of cytochrome c oxidase utilizing high-energy X-rays

2019 ◽  
Vol 26 (4) ◽  
pp. 912-921 ◽  
Author(s):  
Go Ueno ◽  
Atsuhiro Shimada ◽  
Eiki Yamashita ◽  
Kazuya Hasegawa ◽  
Takashi Kumasaka ◽  
...  
Keyword(s):  
Radiation Damage ◽  
Low Dose ◽  
High Energy ◽  
Array Detector ◽  
X Rays ◽  
Data Set ◽  
X Ray ◽  
Ligand Structure ◽  
Biology I ◽  
On Line

To investigate the effect of high-energy X-rays on site-specific radiation-damage, low-dose diffraction data were collected from radiation-sensitive crystals of the metal enzyme cytochrome c oxidase. Data were collected at the Structural Biology I beamline (BL41XU) at SPring-8, using 30 keV X-rays and a highly sensitive pixel array detector equipped with a cadmium telluride sensor. The experimental setup of continuous sample translation using multiple crystals allowed the average diffraction weighted dose per data set to be reduced to 58 kGy, and the resulting data revealed a ligand structure featuring an identical bond length to that in the damage-free structure determined using an X-ray free-electron laser. However, precise analysis of the residual density around the ligand structure refined with the synchrotron data showed the possibility of a small level of specific damage, which might have resulted from the accumulated dose of 58 kGy per data set. Further investigation of the photon-energy dependence of specific damage, as assessed by variations in UV-vis absorption spectra, was conducted using an on-line spectrometer at various energies ranging from 10 to 30 keV. No evidence was found for specific radiation damage being energy dependent.

SPECT and PET Instrumentation

2015 ◽  
Author(s):  
Ernest V. Garcia ◽  
James R. Galt ◽  
Ji Chen
Keyword(s):  
Computed Tomography ◽  
Nuclear Cardiology ◽  
Visual Analysis ◽  
Imaging System ◽  
Photon Emission ◽  
Imaging Systems ◽  
Emission Computed Tomography ◽  
X Rays ◽  
Computer Algorithms ◽  
Contrast Resolution

Nuclear cardiac imaging is solidly based on many branches of science and engineering, including nuclear, optical and mathematical physics, electrical and mechanical engineering, chemistry and biology. This chapter uses principles from these scientific fields to provide an understanding of both the signals used, and the imaging system that captures these signals. Nuclear cardiology’s signals are the x-rays or ?-rays photons emitted from a radioactive tracer and its imaging systems are either single-photon emission computed tomography (SPECT) or positron emission tomography (PET) cameras. This combination has met with remarkable success in clinical cardiology. This success is due to the combination of sophisticated electronic nuclear instruments with a highly specific and thus powerful signal. The signal is as important as or more important than the imaging system. There is a misconception that cardiac magnetic resonance (CMR) cardiac computed tomography (CCT) and echocardiography are superior to nuclear cardiology imaging because of their superior spatial resolution. Yet, in detecting perfusion defects what is really necessary is superior contrast resolution. It is this superior contrast resolution that allows us to differentiate between normal and hypoperfused myocardium facilitating the visual analysis of nuclear cardiology perfusion images. Because these objects are bright compared to the background radioactivity, computer algorithms have been developed that allow us to automatically and objectively process and quantify our images. This chapter explains many of the important scientific principles necessary to understand nuclear cardiology imaging in general, i.e., how these sophisticated imaging systems detect the radiation emitted from the radiotracers.

EOS: A NEW IMAGING SYSTEM WITH LOW DOSE RADIATION IN STANDING POSITION FOR SPINE AND BONE & JOINT DISORDERS

2010 ◽  
Vol 13 (01) ◽  
pp. 1-12 ◽  
Author(s):  
Jean Dubousset ◽  
Georges Charpak ◽  
Wafa Skalli ◽  
Jacques Deguise ◽  
Gabriel Kalifa
Keyword(s):  
3D Reconstruction ◽  
Ct Scan ◽  
Low Dose ◽  
Imaging System ◽  
Standing Position ◽  
Lower Limbs ◽  
Whole Body ◽  
X Rays ◽  
Low Dose Radiation ◽  
Dose Radiation

Very precise combined work between multidisciplinary partners (radiation engineers in physics, engineers in biomechanics, medical radiologists and orthopedic pediatric surgeons) has led to the concept and development of a new low-dose radiation device named EOS. This device has three main advantages: (1) Thanks to the invention of Georges Charpak who designed gaseous detectors for X-rays, the reduction of dose necessary to obtain a good image of skeletal system was 8 to 10 times less for 2D imaging; compared to the dose necessary to obtain a 3D reconstruction from CT scan cuts, the reduction factor was 800 to 1000. (2) The accuracy of 3D reconstruction obtained is better than that of 3D reconstruction from CT scan cuts. (3) The patient in addition gets imaged in a standing functional position, thanks to the AP and lateral X-rays obtained from head to feet simultaneously. This is a big advantage compared to CT scans which are used only in lying position. From the simultaneous AP and lateral X-rays of the whole body obtained via the 3D bone external envelop technique, the biomechanics engineers obtain 3D reconstruction of every level of osteo-articular system, especially for spine, in standing position with an acceptable period of time for reconstruction. This (in spite of the evolution of standing MRI) allows more precise bone reconstruction in orthopedics, especially at the level of the entire skeleton, including the head, spine, pelvis, lower limbs, giving new consideration for physiology, physiopathology and therapeutics.

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