scholarly journals Dynamic X-ray elastography using a pulsed photocathode source

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chika Kamezawa ◽  
Avilash Cramer ◽  
Wolfgang Krull ◽  
Wataru Yashiro ◽  
Kazuyuki Hyodo ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Mechanical Deformation ◽  
Two Dimensional ◽  
Breast Cancers ◽  
Breast Tomosynthesis ◽  
Hard Inclusion ◽  
X Ray ◽  
Breast Phantom ◽  
Surrounding Healthy Tissue ◽  
X Ray Absorption

AbstractX-ray absorption of breast cancers and surrounding healthy tissue can be very similar, a situation that sometimes leads to missed cancers or false-positive diagnoses. To increase the accuracy of mammography and breast tomosynthesis, we describe dynamic X-ray elastography using a novel pulsed X-ray source. This new imaging modality provides both absorption and mechanical properties of the imaged material. We use a small acoustic speaker to vibrate the sample while a synchronously pulsed cold cathode X-ray source images the mechanical deformation. Using these stroboscopic images, we derive two-dimensional stiffness maps of the sample in addition to the conventional X-ray image. In a breast phantom composed of ZrO2 powder embedded in gel, dynamic elastography derived stiffness maps were able to discriminate a hard inclusion from surrounding material with a contrast-to-noise ratio (CNR) of 4.5. The CNR on the corresponding absorption image was 1.1. This demonstrates the feasibility of dynamic X-ray elastography with a synchronously pulsed X-ray source.

scholarly journals Vibrational Effects in X-ray Absorption Spectra of Two-Dimensional Layered Materials

2019 ◽  
Vol 123 (15) ◽  
pp. 9688-9692 ◽  
Author(s):  
Weine Olovsson ◽  
Teruyasu Mizoguchi ◽  
Martin Magnuson ◽  
Stefan Kontur ◽  
Olle Hellman ◽  
...  
Keyword(s):  
Absorption Spectra ◽  
Layered Materials ◽  
Two Dimensional ◽  
X Ray ◽  
X Ray Absorption

ANN-based radar approach to detect breast cancers in fibro-glandular tissues: numerical analysis

2017 ◽  
Vol 9 (8) ◽  
pp. 1597-1602 ◽  
Author(s):  
Salvatore Caorsi ◽  
Claudio Lenzi
Keyword(s):  
Breast Imaging ◽  
Radar Data ◽  
Radar System ◽  
Two Dimensional ◽  
Breast Cancers ◽  
University Of Wisconsin ◽  
Breast Phantom ◽  
Artificial Neural Network Ann ◽  
The University ◽  
Radar Data Processing

This paper presents a new artificial neural network (ANN)-based radar data processing approach for the detection of breast cancers located inside fibro-glandular tissues. The aim is not the breast imaging but detecting tumors through ANN processing of data extracted from the radar signals measured around the breast. The proposed approach has been assessed using several realistic two-dimensional breast geometries derived from the models provided by the numerical breast phantom repository of the University of Wisconsin Cross-Disciplinary Electromagnetic Laboratory (UWCEM). The pulsed radar system was assumed to operate in the mono-static configuration. The obtained results showed the abilities of the proposed approach to detect, for any single radar trace, tumors located inside the fibro-glandular tissues with a sensitivity of 93%, a specificity of 90%, and an overall accuracy of 92%.

XAS and XMCD studies of magnetic properties modifications of Pt/Co/Au and Pt/Co/Pt trilayers induced by Ga+ions irradiation

2015 ◽  
Vol 22 (3) ◽  
pp. 753-759 ◽  
Author(s):  
Piotr Mazalski ◽  
Iosif Sveklo ◽  
Zbigniew Kurant ◽  
Katharina Ollefs ◽  
Andrei Rogalev ◽  
...  
Keyword(s):  
Ion Irradiation ◽  
Magnetic Circular Dichroism ◽  
Perpendicular Magnetic Anisotropy ◽  
Local Environment ◽  
Two Dimensional ◽  
High Fluence ◽  
X Ray ◽  
Plane Anisotropy ◽  
X Ray Absorption ◽  
Reference Samples

Magnetic and magneto-optical properties of Pt/Co/Au and Pt/Co/Pt trilayers subjected to 30 keV Ga+ion irradiation are compared. In two-dimensional maps of these properties as a function of cobalt thickness and ion fluence, two branches with perpendicular magnetic anisotropy (PMA) for Pt/Co/Pt trilayers are well distinguished. The replacement of the Pt capping layer with Au results in the two branches still being visible but the in-plane anisotropy for the low-fluence branch is suppressed whereas the high-fluence branch displays PMA. The X-ray absorption spectra and X-ray magnetic circular dichroism (XMCD) spectra are discussed and compared with non-irradiated reference samples. The changes of their shapes and peak amplitude, particularly for the high-fluence branch, are related to the modifications of the local environment of Co(Pt) atoms and the etching effects induced by ion irradiation. Additionally, in irradiated trilayers the XMCD measurements at the PtL2,3-edge reveal an increase of the magnetic moment induced in Pt atoms.

Development of a two-dimensional imaging system of X-ray absorption fine structure

2012 ◽  
Vol 19 (5) ◽  
pp. 717-721 ◽  
Author(s):  
Misaki Katayama ◽  
Koichi Sumiwaka ◽  
Kazuhiro Hayashi ◽  
Kazuhiko Ozutsumi ◽  
Toshiaki Ohta ◽  
...  
Keyword(s):  
Fine Structure ◽  
Imaging System ◽  
Two Dimensional ◽  
X Ray ◽  
Absorption Fine ◽  
X Ray Absorption

scholarly journals BiVO4/Fe3O4@Polydopamine Superparticles for Tumor Multimodal Imaging and Synergistic Therapy

2021 ◽  
Author(s):  
Ze Wang ◽  
Guan Wang ◽  
Tingting Kang ◽  
Shuwei Liu ◽  
Lu Wang ◽  
...  
Keyword(s):  
Self Assembly ◽  
Multimodal Imaging ◽  
Imaging Modality ◽  
Building Blocks ◽  
Accurate Identification ◽  
X Ray ◽  
Tremendous Progress ◽  
The One ◽  
Oral Epithelial ◽  
X Ray Absorption

Abstract Background: Despite tremendous progress has been achieved in tumor theranostic over the past decade, accurate identification and complete eradication of tumor cells remain a great challenge owing to the limitation of single imaging modality and therapeutic strategy. Results: Herein, we successfully design and construct BiVO4/Fe3O4@polydopamine (PDA) superparticles (SPs) for computed tomography (CT)/photoacoustic (PA)/magnetic resonance (MR) multimodal imaging and radiotherapy (RT)/photothermal therapy (PTT) synergistic therapy toward oral epithelial carcinoma. On the one hand, BiVO4 NPs endow BiVO4/Fe3O4@PDA SPs with impressive X-ray absorption capability due to the high X-ray attenuation coefficient of Bi, which is beneficial for their utilization as radiosensitizers for CT imaging and RT. On the other hand, Fe3O4 NPs impart BiVO4/Fe3O4@PDA SPs with the superparamagnetic property as a T2-weighted contrast agent for MR imaging. Importantly, the aggregation of Fe3O4 NPs in SPs and the presence of PDA shell greatly improve the photothermal conversion capability of SPs, making BiVO4/Fe3O4@PDA SPs as an ideal photothermal transducer for PA imaging and PTT. By integrating advantages of various imaging modalities (CT/PA/MR) and therapeutic strategies (RT/PTT), our BiVO4/Fe3O4@PDA SPs exhibit the sensitive multimodal imaging feature and superior synergistic therapeutic efficacy on tumors. Conclusion: Since there are many kinds of building blocks with unique properties appropriating for self-assembly, our work may largely enrich the library of nanomateirals for tumor diagnosis and treatment.

Breast tomosynthesis: Accuracy of tumor measurement compared with digital mammography and ultrasonography

2010 ◽  
Vol 51 (3) ◽  
pp. 240-247 ◽  
Author(s):  
Daniel Förnvik ◽  
Sophia Zackrisson ◽  
Otto Ljungberg ◽  
Tony Svahn ◽  
Pontus Timberg ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Digital Mammography ◽  
Tumor Size ◽  
Low Dose ◽  
Breast Cancers ◽  
Breast Tomosynthesis ◽  
X Ray ◽  
X Ray Imaging ◽  
Image Volume ◽  
Better Than

Background: Mammographic tumor size measurement can be difficult because breast structures are superimposed onto a two-dimensional (2D) plane, potentially obscuring the tumor outline. Breast tomosynthesis (BT) is a 3D X-ray imaging technique in which low-dose images are acquired over a limited angular range at a total dose comparable to digital mammography (DM). These low-dose images are used to mathematically reconstruct a 3D image volume of the breast, thus reducing the problem of superimposed tissue. Purpose: To investigate whether breast cancer size can be more accurately assessed with breast tomosynthesis than with digital mammography and ultrasonography (US), by reducing the disturbance effect of the projected anatomy. Material and Methods: A prototype BT system was used. The main inclusion criterion for BT examination was subtle but suspicious findings of breast cancer on 2D mammography. Sixty-two women with 73 breast cancers were included. BT, DM, and US sizes were measured independently by experienced radiologists without knowledge of the pathology results, which were used as reference. Results: The tumor outline could be determined in significantly more cases with BT (63) and US (60) than DM (49). BT and US size correlated well with pathology ( R=0.86 and R=0.85, respectively), and significantly better than DM size ( R=0.71). Accordingly, staging was significantly more accurate with BT than with DM. Conclusion: The study indicates that BT is superior to DM in the assessment of breast tumor size and stage.

Cation-intercalated engineering and X-ray absorption spectroscopic characterizations of two dimensional MXenes

2020 ◽  
Vol 31 (4) ◽  
pp. 969-979 ◽  
Author(s):  
Changda Wang ◽  
Shiqiang Wei ◽  
Pengjun Zhang ◽  
Kefu Zhu ◽  
Pin Song ◽  
...  
Keyword(s):  
Two Dimensional ◽  
X Ray ◽  
X Ray Absorption

Antecedents: A Half-Century of Imaging the Breast

2019 ◽  
Vol 1 (1) ◽  
pp. 2-8
Author(s):  
Daniel B Kopans
Keyword(s):  
Breast Cancer ◽  
Magnetic Resonance ◽  
Breast Imaging ◽  
Death Rate ◽  
Digital Breast Tomosynthesis ◽  
Breast Cancers ◽  
Breast Tomosynthesis ◽  
Half Century ◽  
X Ray ◽  
Detect Breast Cancer

Abstract The field of Breast Imaging evolved because a fairly small number of dedicated individuals realized the lifesaving potential of detecting breast cancer earlier. They persevered despite persistent efforts to curtail screening. From the first attempts to produce X-ray images of the breast to magnetic resonance and digital breast tomosynthesis, investigators have worked continuously to develop better ways to detect breast cancer at a time when cure is possible, while working continuously to preserve access for women to screening. Consequently, the death rate from breast cancer has declined by more than 40%. Therapy has improved, but therapy saves lives when breast cancers are treated early.

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