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Parametric Image

About: Parametric Image is a research topic. Over the lifetime, 311 publications have been published within this topic receiving 6095 citations.


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Journal ArticleDOI
01 Oct 2010-Irbm
TL;DR: The robust computation of parametric image volumes enables a local and precise display of the tumor response to an antiangiogenic therapy.
Abstract: Objective A new approach for evaluating tumor response to antiangiogenic treatment using dynamic contrast-enhanced perfusion computed tomography (CT) was provided. Patients and methods Five patients, with hepatic tumors, were examined before and a few weeks after therapy. Following injection of a contrast agent, dynamic image acquisitions were obtained during two minutes, with eight axial sections by volume. To analyze these functional data, we proposed an image processing pipeline. We first applied a rigid registration, based on a blockmatching method, to correct for respiratory motion. We then calculated parametric image volumes, using adapted reference kinetics. These image volumes allowed us to differentiate between the various contrast enhancement kinetics (arterial/venous, healthy/pathological tissues), following the injection of contrast agent. Results The registration was validated qualitatively (by visual inspection of registered image volumes) and quantitatively (using criteria based on the estimation of a respiratory motion component). Parametric image volumes allowed us to differentiate healthy tissues from tumor tissues, and to display necrotic regions, which occurred in four patients, after therapy. Discussion The proposed approach allows us to compensate for respiratory motion in a region localized around the tumor and could be further extended by a nonrigid registration. Conclusion The robust computation of parametric image volumes enables a local and precise display of the tumor response to an antiangiogenic therapy.

8 citations

Journal Article
TL;DR: The attenuating properties of biological tissue are of great importance in ultrasonic examination even though its anatomical variability limits diagnostics effectiveness, and a technique for parametric imaging of attenuation is currently developing.
Abstract: The attenuating properties of biological tissue are of great importance in ultrasonic examination even though its anatomical variability limits diagnostics effectiveness. We are currently developing a technique for parametric imaging of attenuation and we intend to apply it for in vivo characterization of tissue. The diagnostic usefulness of the proposed technique crucially depends on the precision of the attenuation estimate and the resolution of the parametric image. These two parameters are highly correlated, since the resolution is reduced whenever averaging is used to minimize the errors introduced by the random character of the backscatter. Here we report on the results of numerical processing of both, simulated and recorded from a tissue-mimicking phantom echoes. We have analyzed the parameters of the estimation technique and examined their influence on the precision of the attenuation estimate and on the parametric image resolution. The optimal selection of attenuation image parameters depending on its intended diagnostic use, was also considered.

8 citations

Journal ArticleDOI
TL;DR: Parametric imaging is a very useful way of facilitating straightforward visualization of the level of blood flow within HCC and the distribution of histopathological findings in single static images.
Abstract: To clarify the usefulness of parametric imaging using contrast-enhanced ultrasound (CE-US) with Sonazoid by comparing parametric images of hepatocellular carcinoma (HCC) with histopathological findings. Two patients with HCCs underwent CE-US with Sonazoid before surgical resection. A single focus point was set at the lower margin of the tumor, and a bolus intravenous injection of Sonazoid (0.5 ml) was administered. Images of the ideal scanning plane were displayed in real-time mode for the early vascular phase. We analyzed these images using prototype PC software. The software watches, pixel by pixel, the increase in the intensity due to the inflow of the microbubbles, and displays colors if the intensity becomes larger than a certain threshold. Parametric images were compared with histopathological findings. The level of blood flow in the tumor could be visually evaluated using a single image by expressing the detailed hemodynamics of the tumor in terms of differences in color using a time axis appropriate for each case. Parametric imaging is a very useful way of facilitating straightforward visualization of the level of blood flow within HCC and the distribution of histopathological findings in single static images.

8 citations

Journal ArticleDOI
TL;DR: In this article, the quantum theory of parametric image amplification at low-frequency pumping was developed for the first time, which takes into account the diffraction effect and group mismatch of interacting waves.
Abstract: We develop for the first time the quantum theory of parametric image amplification at low-frequency pumping. Such a process can be implemented by coupled consecutive three-frequency optical interactions. As a result, besides the amplified optical image on the signal frequency, there are two other images with frequencies which are below the pumping frequency. The theory developed takes into account the diffraction effect and group mismatch of interacting waves. For the interacting waves the expressions for mean photon numbers and signal-to-noise ratios are deduced and the dependence of these parameters on the interaction length and coordinate at the image plane are studied.

8 citations

Journal ArticleDOI
TL;DR: This work proposes a TV‐based algorithm for parametric image generation in intravoxel incoherent motion (IVIM) diffusion‐weighted magnetic resonance imaging (DW‐MRI) and proposes a new total variation method for image restoration and reconstruction.
Abstract: Purpose Total variation (TV) method has been used widely for image restoration and reconstruction In this work, we propose a TV-based algorithm for parametric image generation in intravoxel incoherent motion (IVIM) diffusion-weighted magnetic resonance imaging (DW-MRI) Methods We used simulated and real data to investigate whether the proposed TV-based method can provide reliable parametric images Parametric images of IVIM parameters including perfusion fraction (PF), diffusion coefficient (D), and pseudo-diffusion coefficient (D*) were estimated using DW-MRI data and TV through fitting the IVIM model The Levenberg-Marquardt (LM) method, which has often been used in the context of IVIM analysis, was employed as the standard method for comparison of the resulting parametric images Results The simulation results show that the proposed method outperforms the LM algorithm in terms of precision, providing a 40–81%, 90–93%, and 68–84% improvement for PF, D and D*, respectively, at signal-to-noise ratio (SNR) of 30 For real data, the proposed method showed an average five-fold, three-fold, and four-fold improvement in the SNR for PF, D and D*, respectively Conclusion We introduced the use of TV to produce parametric images, and demonstrated that the proposed TV-based method is effective in improving the parametric image quality Magn Reson Med, 2016 © 2016 International Society for Magnetic Resonance in Medicine

8 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20217
202013
201911
20186
201713
201613