The Experts below are selected from a list of 392205 Experts worldwide ranked by ideXlab platform

A. S K Dzik-jurasz - One of the best experts on this subject based on the ideXlab platform.

  • The role of Clinical Imaging in oncological drug development
    British Journal of Radiology, 2008
    Co-Authors: Philip S. Murphy, T. J. Mccarthy, A. S K Dzik-jurasz
    Abstract:

    Clinical Imaging has the potential to provide key biomarkers to inform decision-making in drug development. There is considerable optimism that emerging functional Imaging techniques will substantially add to the conventional morphological depiction of disease. The discovery, development and qualification of Clinical Imaging biomarkers remain a considerable undertaking. Once an Imaging biomarker is developed, it must be implemented with a high degree of consistency to ensure the collection of robust Clinical trial data. The aim of such a development and implementation process is to deliver sufficient confidence in an Imaging biomarker to support "go/no-go" decisions made in a drug development programme. This article outlines the drug development process, with a focus on the current impact of Clinical Imaging on drug development and its probable future direction.

Paul E Kinaha - One of the best experts on this subject based on the ideXlab platform.

  • Clinical Imaging characteristics of the positron emission mammography camera pem flex solo ii
    The Journal of Nuclear Medicine, 2009
    Co-Authors: Lawrence R. Macdonald, James V. Rogers, Joh Edwards, T K Lewelle, David Haseley, Paul E Kinaha
    Abstract:

    Positron emission mammography (PEM) is a technique using 2 annihilation-photon detectors and limited-angle tomographic reconstruction to image radiotracer distributions within the breast. Because of their smaller size and closer proximity to the source, dedicated PEM cameras can provide better spatial resolution and count sensitivity than whole-body PET (WB PET). PEM is undergoing Clinical trials and has been suggested for breast cancer detection, characterization, treatment planning, and assessment of response to therapy. PEM, like WB PET, provides functional Imaging information. Radiographic mammography, ultrasound, and MRI primarily provide anatomic information. PEM can thus provide complementary information to conventional breast Imaging modalities. Screening mammography is believed to be an important factor in recent declines in breast cancer mortality (1). Despite the successes of earlier detection by mammography, however, breast cancer is the second-leading cause of cancer-related deaths in North American women. This statistic shows a clear need for improved methods to fight breast cancer. WB PET has been used for Imaging breast cancer for many years (2-4). Modern WB PET systems typically have a reconstructed spatial resolution of 5–7 mm full width at half maximum (FWHM). In practice, however, reconstructed resolution is 10–15 mm in FWHM because of added smoothing. Partial-volume effects on these systems limit qualitative assessment and quantitative accuracy for lesions smaller than approximately 25–30 mm. This technical limitation of WB PET and the inherent variability of the disease have resulted in variable sensitivity and specificity of breast PET for lesions approximately 10 mm and smaller (3). Hence, breast lesions accurately imaged using WB PET are associated with relatively advanced disease. Ideally, cancer is treated in the early stages of the disease. The idea of dedicated PEM systems is to reduce the size threshold for accurate Imaging and assist earlier intervention. PEM was proposed in the 1990s by Thompson et al. (5) and has continued to receive attention from the research community (6-8). Some of these devices have undergone preliminary Clinical testing (9-13). These tests have mostly been small in scope and have used prototype devices. Although preliminary indications are encouraging, conclusions are that larger, focused studies with mature PEM technology are required to establish a role for PEM. Even with an available array of Imaging agents (14), and the evident need for improved specificity, the role of PEM in the diagnosis and treatment of breast cancer is yet to be established. At the Swedish Cancer Institute, the PEM Flex Solo II (Naviscan PET Systems, Inc.) has been used since July 2007 to image breast cancer patients who have already been diagnosed and are receiving a WB PET/CT examination. Dedicated breast PET and PEM systems are still in the early stages of development and implementation. No camera-testing standards have been developed for these systems. As with small-animal PET scanners, conventional WB PET testing standards are inappropriate for characterizing dedicated breast Imaging systems because of their distinct design. In this work, we tested several common Imaging parameters using the standard Clinical operating mode of the PEM Flex system. Spatial resolution, counting-rate linearity, uniformity, and recovery coefficients (RCs) were measured. In addition, we investigated properties relevant to the breast Imaging application, namely Imaging characteristics at the edge of the field of view (FOV), which is important for Imaging posterior breast lesions. Independently, the PEM Flex Solo II was recently characterized using the NU 4-2008 Small Animal PET Standard of the National Electrical Manufacturers Association (NEMA) (15).

Heiko G. Niessen - One of the best experts on this subject based on the ideXlab platform.

  • Clinical Imaging in anti-atherosclerosis drug development
    Drug discovery today, 2015
    Co-Authors: Alexander Ehlgen, Anders Bylock, Jörg Kreuzer, Michael Koslowski, Florian Gantner, Heiko G. Niessen
    Abstract:

    The development of novel drugs for the treatment of atherosclerosis faces many challenges, particularly caused by the need for large and costly outcome trials. When predictive biochemical biomarkers are not available, Clinical Imaging data can serve as intermediate Phase II endpoints to demonstrate mechanistic and anti-atherosclerotic activity of new compounds. These data can support risk mitigation before continuing development in large Phase III outcome trials. Imaging techniques such as magnetic resonance Imaging (MRI), computed tomography (CT) and ultrasound [intima-media thickness (IMT) and intravascular ultrasound (IVUS)] can provide detailed information on vascular plaque volume and morphology, whereas functional changes can potentially be captured by positron emission tomography (PET) techniques in the vessel wall. We will review the application and operational aspects of Clinical Imaging methods and endpoints used in interventional atherosclerosis trials.

Lawrence R. Macdonald - One of the best experts on this subject based on the ideXlab platform.

  • Clinical Imaging characteristics of the positron emission mammography camera pem flex solo ii
    The Journal of Nuclear Medicine, 2009
    Co-Authors: Lawrence R. Macdonald, James V. Rogers, Joh Edwards, T K Lewelle, David Haseley, Paul E Kinaha
    Abstract:

    Positron emission mammography (PEM) is a technique using 2 annihilation-photon detectors and limited-angle tomographic reconstruction to image radiotracer distributions within the breast. Because of their smaller size and closer proximity to the source, dedicated PEM cameras can provide better spatial resolution and count sensitivity than whole-body PET (WB PET). PEM is undergoing Clinical trials and has been suggested for breast cancer detection, characterization, treatment planning, and assessment of response to therapy. PEM, like WB PET, provides functional Imaging information. Radiographic mammography, ultrasound, and MRI primarily provide anatomic information. PEM can thus provide complementary information to conventional breast Imaging modalities. Screening mammography is believed to be an important factor in recent declines in breast cancer mortality (1). Despite the successes of earlier detection by mammography, however, breast cancer is the second-leading cause of cancer-related deaths in North American women. This statistic shows a clear need for improved methods to fight breast cancer. WB PET has been used for Imaging breast cancer for many years (2-4). Modern WB PET systems typically have a reconstructed spatial resolution of 5–7 mm full width at half maximum (FWHM). In practice, however, reconstructed resolution is 10–15 mm in FWHM because of added smoothing. Partial-volume effects on these systems limit qualitative assessment and quantitative accuracy for lesions smaller than approximately 25–30 mm. This technical limitation of WB PET and the inherent variability of the disease have resulted in variable sensitivity and specificity of breast PET for lesions approximately 10 mm and smaller (3). Hence, breast lesions accurately imaged using WB PET are associated with relatively advanced disease. Ideally, cancer is treated in the early stages of the disease. The idea of dedicated PEM systems is to reduce the size threshold for accurate Imaging and assist earlier intervention. PEM was proposed in the 1990s by Thompson et al. (5) and has continued to receive attention from the research community (6-8). Some of these devices have undergone preliminary Clinical testing (9-13). These tests have mostly been small in scope and have used prototype devices. Although preliminary indications are encouraging, conclusions are that larger, focused studies with mature PEM technology are required to establish a role for PEM. Even with an available array of Imaging agents (14), and the evident need for improved specificity, the role of PEM in the diagnosis and treatment of breast cancer is yet to be established. At the Swedish Cancer Institute, the PEM Flex Solo II (Naviscan PET Systems, Inc.) has been used since July 2007 to image breast cancer patients who have already been diagnosed and are receiving a WB PET/CT examination. Dedicated breast PET and PEM systems are still in the early stages of development and implementation. No camera-testing standards have been developed for these systems. As with small-animal PET scanners, conventional WB PET testing standards are inappropriate for characterizing dedicated breast Imaging systems because of their distinct design. In this work, we tested several common Imaging parameters using the standard Clinical operating mode of the PEM Flex system. Spatial resolution, counting-rate linearity, uniformity, and recovery coefficients (RCs) were measured. In addition, we investigated properties relevant to the breast Imaging application, namely Imaging characteristics at the edge of the field of view (FOV), which is important for Imaging posterior breast lesions. Independently, the PEM Flex Solo II was recently characterized using the NU 4-2008 Small Animal PET Standard of the National Electrical Manufacturers Association (NEMA) (15).

  • Clinical Imaging characteristics of the positron emission mammography PEM Flex Solo II
    2008 IEEE Nuclear Science Symposium Conference Record, 2008
    Co-Authors: Lawrence R. Macdonald, John Edwards, Thomas K. Lewellen, James V. Rogers, Paul E. Kinahan
    Abstract:

    Positron emission mammography (PEM) uses two opposing gamma-ray imagers and limited-angle tomography techniques to image radiotracer distributions within the breast. Due to their smaller size and closer proximity to the source, dedicated PEM cameras can provide better spatial resolution and count sensitivity than whole-body positron emission tomographs. We performed several Clinical Imaging tests on a commercially available PEM camera, the PEM Flex Solo II. This system is comprised of two opposing 6 cm X 16.4 cm detectors that scan in unison to cover up to a 24 cm X 16.4 cm field of view (FOV). We measured spatial resolution, uniformity, recovery coefficients (RC), and quantification using the system Clinical software. Image linearity and coefficient of variation (CV) at the edge of the FOV were also characterized. Anecdotal examples of Clinical patient data are presented. Spatial resolution is 2.4 mm FWHM for image planes parallel to the detector faces; background variability is 6%; quantification and RC varied within the FOV; positioning linearity began at ∼ 13 mm from the edge of the detector housing; CV increased rapidly at the edge of the FOV due to limited sampling in these image planes.

John D. Hazle - One of the best experts on this subject based on the ideXlab platform.

  • WE‐EF‐204‐01: Pre‐Clinical Imaging for Co‐Clinical Trials
    Medical Physics, 2015
    Co-Authors: John D. Hazle
    Abstract:

    As molecular biology breakthroughs in understanding cancers and other diseases, hundreds of new drugs wait testing. In the last decade, mouse models have been evolved to better mimic human diseases genetically and biologically. These reliable mouse models allow us to determine which genetic elements, pathways and mutations impact on therapy. The co-Clinical trial strategy is to conduct a human Clinical trial for a therapeutic drug and test it in mouse models at the same time. This strategy has the potential to accelerate the drug testing process and identify the patient population that will respond to the drug. Imaging plays an important role in co-Clinical trials. In this symposium, four speakers will discuss advancements and issues in pre-Clinical Imaging, murine models, Imaging hardware and software, and funding opportunities in co-Clinical trials. Learning Objectives: 1.  Multi-modality pre-Clinical Imaging hardware and software, and new technologies (e.g., hyperpolarized MRI) 2.  Selection of animal models from physiological and genetic perspectives with examples in colon, pancreatic and lung cancers 3.  NCI funding opportunities