A Retroreflection Reduction Technique Based on the Wavefront Coded Imaging System

A novel anti-cat-eye effect imaging technique based on wavefront coding is proposed as a solution to the problem of previous anti-cat-eye effect imaging techniques where imaging quality was sacrificed to reduce the retroreflection from the photoelectric imaging equipment. With the application of the Fresnel–Kirchhoff diffraction theory, and the definition of generalized pupil function combining both phase modulation and defocus factors, the cat-eye echo formation of the wavefront coded imaging system is theoretically modeled. Based on the physical model, the diffracted spot profile distribution and the light intensity distribution on the observation plane are further simulated with the changes in the defocus parameter and the phase modulation coefficient. A verification test on the cat-eye laser echo power of the wavefront coded imaging system and that of the conventional imaging system at a 20 m distance are conducted, respectively. Simulations and experiment results show that compared with conventional imaging systems, the wavefront coding imaging system can reduce the retroreflection echo by two orders of magnitude while maintaining better imaging quality through defocusing.

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Optical Aberration Calibration and Correction of Photographic System Based on Wavefront Coding

Sensors ◽

10.3390/s21124011 ◽

2021 ◽

Vol 21 (12) ◽

pp. 4011

Author(s):

Chuanwei Yao ◽

Yibing Shen

Keyword(s):

Imaging System ◽

Optical Design ◽

Computational Imaging ◽

Large Field ◽

Wavefront Aberration ◽

Imaging Method ◽

Image Deconvolution ◽

Pupil Function ◽

Wavefront Coding ◽

Blurred Images

The image deconvolution technique can recover potential sharp images from blurred images affected by aberrations. Obtaining the point spread function (PSF) of the imaging system accurately is a prerequisite for robust deconvolution. In this paper, a computational imaging method based on wavefront coding is proposed to reconstruct the wavefront aberration of a photographic system. Firstly, a group of images affected by local aberration is obtained by applying wavefront coding on the optical system’s spectral plane. Then, the PSF is recovered accurately by pupil function synthesis, and finally, the aberration-affected images are recovered by image deconvolution. After aberration correction, the image’s coefficient of variation and mean relative deviation are improved by 60% and 30%, respectively, and the image can reach the limit of resolution of the sensor, as proved by the resolution test board. Meanwhile, the method’s robust anti-noise capability is confirmed through simulation experiments. Through the conversion of the complexity of optical design to a post-processing algorithm, this method offers an economical and efficient strategy for obtaining high-resolution and high-quality images using a simple large-field lens.

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Cardiotoxic effects and myocardial injury: the search for a more precise definition of drug cardiotoxicity

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2020-0566 ◽

2021 ◽

Vol 59 (1) ◽

pp. 51-57

Author(s):

Daniela Maria Cardinale ◽

Martina Zaninotto ◽

Carlo Maria Cipolla ◽

Claudio Passino ◽

Mario Plebani ◽

...

Keyword(s):

Early Detection ◽

Myocardial Injury ◽

Randomized Clinical Trials ◽

Imaging Techniques ◽

Left Ventricular ◽

Left Ventricular Ejection ◽

Cardiac Imaging Techniques ◽

Ventricular Ejection Fraction ◽

Early Evaluation ◽

Definition Of

AbstractDrug-induced cardiotoxicity is a major clinical problem; cardiotoxic drugs may induce both cardiac dysfunction and myocardial injury. Several recent studies reported that cardiac troponins measured with high-sensitivity methods (hs-cTn) can enable the early detection of myocardial injury related to chemotherapy or abuse of drugs that are potentially cardiotoxic. Several authors have some concerns about the standard definition of cardiotoxicity, in particular, regarding the early evaluation of chemotherapy cardiotoxicity in cancer patients. Several recent studies using the hs-cTn assay indicate that myocardial injury may precede by some months or years the diagnosis of heart failure (HF) based on the evaluation of left ventricular ejection fraction (LVEF). Accordingly, hs-cTn assay should considered to be a reliable laboratory test for the early detection of asymptomatic or subclinical cardiotoxic damage in patients undergoing cancer chemotherapy. In accordance with the Fourth Universal Definition of Myocardial Infarction and also taking into account the recent experimental and clinical evidences, the definition of drug-cardiotoxicity should be updated considering the early evaluation of myocardial injury by means of hs-cTn assay. It is conceivable that the combined use of hs-cTn assay and cardiac imaging techniques for the evaluation of cardiotoxicity will significantly increase both diagnostic sensitivity and specificity, and also better prevent chemotherapy-related left ventricular (LV) dysfunction and other adverse cardiac events. However, large randomized clinical trials are needed to evaluate the cost/benefit ratio of standardized protocols for the early detection of cardiotoxicity using hs-cTn assay in patients receiving chemotherapy for malignant diseases.

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BIMG-04. MAPPING HETEROGENEITY OF HIGH-GRADE GLIOMA METABOLISM USING HIGH RESOLUTION 7T MRSI

Neuro-Oncology Advances ◽

10.1093/noajnl/vdab024.003 ◽

2021 ◽

Vol 3 (Supplement_1) ◽

pp. i1-i1

Author(s):

Gilbert Hangel ◽

Cornelius Cadrien ◽

Philipp Lazen ◽

Sukrit Sharma ◽

Julia Furtner ◽

...

Keyword(s):

High Resolution ◽

Imaging Techniques ◽

Basis Set ◽

Metabolic Imaging ◽

Tumor Segmentation ◽

Low Grade ◽

High Grade ◽

Isotropic Resolution ◽

Contrast Enhanced ◽

Definition Of

Abstract OBJECTIVES Neurosurgical resection in gliomas depends on the precise preoperative definition of the tumor and its margins to realize a safe maximum resection that translates into a better patient outcome. New metabolic imaging techniques could improve this delineation as well as designate targets for biopsies. We validated the performance of our fast high-resolution whole-brain 3D-magnetic resonance spectroscopic imaging (MRSI) method at 7T in high-grade gliomas (HGGs) as first step to this regard. METHODS We measured 23 patients with HGGs at 7T with MRSI covering the whole cerebrum with 3.4mm isotropic resolution in 15 min. Quantification used a basis-set of 17 neurochemical components. They were evaluated for their reliability/quality and compared to neuroradiologically segmented tumor regions-of-interest (necrosis, contrast-enhanced, non-contrast-enhanced+edema, peritumoral) and histopathology (e.g., grade, IDH-status). RESULTS We found 18/23 measurements to be usable and ten neurochemicals quantified with acceptable quality. The most common denominators were increases of glutamine, glycine, and total choline as well as decreases of N-acetyl-aspartate and total creatine over most tumor regions. Other metabolites like taurine and serine showed mixed behavior. We further found that heterogeneity in the metabolic images often continued into the peritumoral region. While 2-hydroxy-glutarate could not be satisfyingly quantified, we found a tendency for a decrease of glutamate in IDH1-mutant HGGs. DISCUSSION Our findings corresponded well to clinical tumor segmentation but were more heterogeneous and often extended into the peritumoral region. Our results corresponded to previous knowledge, but with previously not feasible resolution. Apart from glycine/glutamine and their role in glioma progression, more research on the connection of glutamate and others to specific mutations is necessary. The addition of low-grade gliomas and statistical ROI analysis in a larger cohort will be the next important steps to define the benefits of our 7T MRSI approach for the definition of spatial metabolic tumor profiles.

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Treatment of nonmetastatic castration-resistant prostate cancer: focus on second-generation androgen receptor inhibitors

Prostate Cancer and Prostatic Diseases ◽

10.1038/s41391-020-00310-3 ◽

2021 ◽

Author(s):

Fred Saad ◽

Martin Bögemann ◽

Kazuhiro Suzuki ◽

Neal Shore

Keyword(s):

Prostate Cancer ◽

Androgen Receptor ◽

Second Generation ◽

Imaging Techniques ◽

Specific Antigen ◽

Conventional Imaging ◽

Castration Resistant Prostate Cancer ◽

Castration Resistant ◽

Therapeutic Decisions ◽

Consensus Statements

Abstract Background Nonmetastatic castration-resistant prostate cancer (nmCRPC) is defined as a rising prostate-specific antigen concentration, despite castrate levels of testosterone with ongoing androgen-deprivation therapy or orchiectomy, and no detectable metastases by conventional imaging. Patients with nmCRPC progress to metastatic disease and are at risk of developing cancer-related symptoms and morbidity, eventually dying of their disease. While patients with nmCRPC are generally asymptomatic from their disease, they are often older and have chronic comorbidities that require long-term concomitant medication. Therefore, careful consideration of the benefit–risk profile of potential treatments is required. Methods In this review, we will discuss the rationale for early treatment of patients with nmCRPC to delay metastatic progression and prolong survival, as well as the factors influencing this treatment decision. We will focus on oral pharmacotherapy with the second-generation androgen receptor inhibitors, apalutamide, enzalutamide, and darolutamide, and the importance of balancing the clinical benefit they offer with potential adverse events and the consequential impact on quality of life, physical capacity, and cognitive function. Results and conclusions While the definition of nmCRPC is well established, the advent of next-generation imaging techniques capable of detecting hitherto undetectable oligometastatic disease in patients with nmCRPC has fostered debate on the criteria that inform the management of these patients. However, despite these developments, published consensus statements have maintained that the absence of metastases on conventional imaging suffices to guide such therapeutic decisions. In addition, the prolonged metastasis-free survival and recently reported positive overall survival outcomes of the three second-generation androgen receptor inhibitors have provided further evidence for the early use of these agents in patients with nmCRPC in order to delay metastases and prolong survival. Here, we discuss the benefit–risk profiles of apalutamide, enzalutamide, and darolutamide based on the data available from their pivotal clinical trials in patients with nmCRPC.

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Phase transfer function based method to alleviate image artifacts in wavefront coding imaging system

10.1117/12.2034741 ◽

2013 ◽

Cited By ~ 6

Author(s):

Xutao Mo ◽

Jinjiang Wang

Keyword(s):

Transfer Function ◽

Phase Transfer ◽

Imaging System ◽

Image Artifacts ◽

Wavefront Coding

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Prediction of Recurrence after HCC Resection

Acta Radiologica ◽

10.1177/028418519403500404 ◽

1994 ◽

Vol 35 (4) ◽

pp. 329-334 ◽

Cited By ~ 2

Author(s):

M. Yamamoto ◽

Y. Iimuro ◽

M. Mogaki ◽

K. Kachi ◽

H. Fujii ◽

...

Keyword(s):

Imaging Techniques ◽

Tumor Vasculature ◽

The Other ◽

High Recurrence Rate ◽

Small Hepatocellular Carcinoma ◽

Conventional Imaging ◽

Cumulative Survival ◽

Preoperative Ct ◽

Small Hcc ◽

Better Than

In trying to clarify the high recurrence rate after removal of small hepatocellular carcinoma (HCC), we assessed the postoperative evolution of minute hepatic Lipiodol deposits which had been diagnosed as artifacts on the preoperative Lipiodol-CT. Of 27 patients with solitary HCC less than 5 cm in diameter, 14 had such Lipiodol deposits in the preoperative CT and 9 of them (64%) developed recurrent tumors. On the other hand, 6 of the 13 patients without deposits (46%) suffered recurrence, but in 5 of these 6 patients the HCC was metachronous multicentric. The cumulative survival rate of the non-deposit group was better than that of the deposit group (p < 0.1). The present study suggested that, even in patients with small HCC, minute concomitant tumors invisible by conventional imaging techniques may exist at the time of surgery. Some of these lesions without sufficient tumor vasculature showing a hypervascular blush on angiography appear to retain small, vague Lipiodol deposits.

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Diabetes, Obesity, and Inflammation: Impact on Clinical and Radiographic Features of Breast Cancer

International Journal of Molecular Sciences ◽

10.3390/ijms22052757 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2757

Author(s):

Braden Miller ◽

Hunter Chalfant ◽

Alexandra Thomas ◽

Elizabeth Wellberg ◽

Christina Henson ◽

...

Keyword(s):

Breast Cancer ◽

Imaging Techniques ◽

Growth Factor Receptor ◽

Breast Cancer Diagnosis ◽

Screening Mammography ◽

Imaging Modalities ◽

Conventional Imaging ◽

Obese Women ◽

Detection Rates ◽

Therapeutic Decision Making

Obesity, diabetes, and inflammation increase the risk of breast cancer, the most common malignancy in women. One of the mainstays of breast cancer treatment and improving outcomes is early detection through imaging-based screening. There may be a role for individualized imaging strategies for patients with certain co-morbidities. Herein, we review the literature regarding the accuracy of conventional imaging modalities in obese and diabetic women, the potential role of anti-inflammatory agents to improve detection, and the novel molecular imaging techniques that may have a role for breast cancer screening in these patients. We demonstrate that with conventional imaging modalities, increased sensitivity often comes with a loss of specificity, resulting in unnecessary biopsies and overtreatment. Obese women have body size limitations that impair image quality, and diabetes increases the risk for dense breast tis-sue. Increased density is known to obscure the diagnosis of cancer on routine screening mammography. Novel molecu-lar imaging agents with targets such as estrogen receptor, human epidermal growth factor receptor 2 (HER2), pyrimi-dine analogues, and ligand-targeted receptor probes, among others, have potential to reduce false positive results. They can also improve detection rates with increased resolution and inform therapeutic decision making. These emerg-ing imaging techniques promise to improve breast cancer diagnosis in obese patients with diabetes who have dense breasts, but more work is needed to validate their clinical application.

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Fast, Robust, and Low-Cost Microwave Imaging of Multiple Non-Metallic Pipes

Electronics ◽

10.3390/electronics10151762 ◽

2021 ◽

Vol 10 (15) ◽

pp. 1762

Author(s):

Yuki Gao ◽

Maryam Ravan ◽

Reza K. Amineh

Keyword(s):

Antenna Arrays ◽

Oil And Gas ◽

Imaging System ◽

Imaging Techniques ◽

Low Cost ◽

Microwave Imaging ◽

Airport Security ◽

Destructive Testing ◽

Security Screening ◽

Industrial Sectors

The use of non-metallic pipes and composite components that are low-cost, durable, light-weight, and resilient to corrosion is growing rapidly in various industrial sectors such as oil and gas industries in the form of non-metallic composite pipes. While these components are still prone to damages, traditional non-destructive testing (NDT) techniques such as eddy current technique and magnetic flux leakage technique cannot be utilized for inspection of these components. Microwave imaging can fill this gap as a favorable technique to perform inspection of non-metallic pipes. Holographic microwave imaging techniques are fast and robust and have been successfully employed in applications such as airport security screening and underground imaging. Here, we extend the use of holographic microwave imaging to inspection of multiple concentric pipes. To increase the speed of data acquisition, we utilize antenna arrays along the azimuthal direction in a cylindrical setup. A parametric study and demonstration of the performance of the proposed imaging system will be provided.

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