Saturday 6 August 2016

Abnormal Choline Phospholipid Metabolism in Breast and Ovary Cancer:Molecular Bases for Noninvasive Imaging Approaches

Author(s):

Franca Podo, Francesco Sardanelli, Egidio Iorio, Rossella Canese, Giulia Carpinelli, Alfonso Fausto and Silvana CanevariPages 123-137 (15)

Abstract:


Elevated contents of choline phospholipid metabolites are typically detected by nuclear magnetic resonance spectroscopy (MRS) in human and animal tumors. An increase in the intensity of the 1H-MRS profile of total cholinecontaining compounds (tCho, 3.2 ppm) is today considered as a common feature in different types of cancer, beyond their otherwise wide phenotypic variability. This finding fostered investigations on the molecular mechanisms underlying the observed spectral changes and on correlations between aberrant phospholipid metabolism and tumor progression. At the clinical level, efforts are addressed to evaluate effectiveness and potential use of in vivo localized MRS and choline-based positron emission tomography (Cho-PET) in cancer diagnosis. Aims of this article are: a) to overview recent advances in the identification of biochemical pathways responsible for the altered 1H-MRS tCho profile in breast and ovary cancer cells, as a basis for interpreting in vivo MR spectra and enhanced uptake of radiolabeled choline in PET; b) to summarize recent developments of in vivo 1H-MRS methods in breast cancer diagnosis; c) to discuss the potentialities of complementing current diagnostic modalities with noninvasive MRS and Cho-PET methods to monitor biochemical alterations associated with progression, relapse and therapy response in ovary cancer.

Keywords:

Breast cancer, ovary cancer, choline metabolism, phosphatidylcholine cycle, 1H-MRS, PET

Affiliation:

Department of Cell Biology and Neurosciences, Istituto Superiore di Sanita, Viale Regina Elena 299,00161 Rome, Italy.


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Viewpoints on Medical Image Processing: From Science to Application

Author(s):

Thomas M. Deserno (ne Lehmann), Heinz Handels, Klaus H. Maier-Hein (ne Fritzsche), Sven Mersmann, Christoph Palm, Thomas Tolxdorff, Gudrun Wagenknecht and Thomas WittenbergPages 79-88 (10)

Abstract:


Medical image processing provides core innovation for medical imaging. This paper is focused on recent developments from science to applications analyzing the past fifteen years of history of the proceedings of the German annual meeting on medical image processing (BVM). Furthermore, some members of the program committee present their personal points of views: (i) multi-modality for imaging and diagnosis, (ii) analysis of diffusion-weighted imaging, (iii) model-based image analysis, (iv) registration of section images, (v) from images to information in digital endoscopy, and (vi) virtual reality and robotics. Medical imaging and medical image computing is seen as field of rapid development with clear trends to integrated applications in diagnostics, treatment planning and treatment.

Keywords:

Medical imaging, Image processing, Image analysis, Visualization, Multi-modal imaging, Diffusion-weighted imaging, Model-based imaging, Registration, Digital endoscopy, Virtual reality, Robotics.

Affiliation:

Department of Medical Informatics, Uniklinik RWTH Aachen 52057, Germany.


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Acoustic Inversion in Optoacoustic Tomography: A Review

Author(s):

Amir Rosenthal, Vasilis Ntziachristos and Daniel RazanskyPages 318-336 (19)

Abstract:


Optoacoustic tomography enables volumetric imaging with optical contrast in biological tissue at depths beyond the optical mean free path by the use of optical excitation and acoustic detection. The hybrid nature of optoacoustic tomography gives rise to two distinct inverse problems: The optical inverse problem, related to the propagation of the excitation light in tissue, and the acoustic inverse problem, which deals with the propagation and detection of the generated acoustic waves. Since the two inverse problems have different physical underpinnings and are governed by different types of equations, they are often treated independently as unrelated problems. From an imaging standpoint, the acoustic inverse problem relates to forming an image from the measured acoustic data, whereas the optical inverse problem relates to quantifying the formed image. This review focuses on the acoustic aspects of optoacoustic tomography, specifically acoustic reconstruction algorithms and imaging-system practicalities. As these two aspects are intimately linked, and no silver bullet exists in the path towards high-performance imaging, we adopt a holistic approach in our review and discuss the many links between the two aspects. Four classes of reconstruction algorithms are reviewed: time-domain (so called back-projection) formulae, frequency-domain formulae, time-reversal algorithms, and model-based algorithms. These algorithms are discussed in the context of the various acoustic detectors and detection surfaces which are commonly used in experimental studies. We further discuss the effects of non-ideal imaging scenarios on the quality of reconstruction and review methods that can mitigate these effects. Namely, we consider the cases of finite detector aperture, limited-view tomography, spatial under-sampling of the acoustic signals, and acoustic heterogeneities and losses.

Keywords:

Optoacoustic imaging, photoacoustic imaging, tomography, inverse problems, ultrasound detectors, algorithms, acoustic waves.

Affiliation:

Institute for Biological and Medical Imaging, Helmholtz Zentrum Munchen, Ingoldstadter Landstraße 1, Neuherberg 85764, Germay and Chair for Biological Imaging, Technische Universitat München, Ismaninger Str. 22, Munchen 81675, Germany.


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The Correspondence Between Magnetic Resonance Images and the Clinical and Intraoperative Status of Patients with Spinal Tumors

Author(s):

Grzegorz GuzikPages 149-155 (7)

Abstract:


Introduction: Surgical treatment of tumors, particularly metastases to the spine, has become increasingly common owing to the progress in anesthesiology and spinal surgery and greater detectability. The patients qualified for surgeries are those with mechanical pain, fracture or at risk of vertebral fracture or neurological complications. The basis for qualification for different types of surgeries is clinical and imaging examination, particularly MRI and CT. Qualification should always be multidisciplinary and requires understanding and knowledge of its most essential aspects. When carrying out imaging examinations, it is necessary to assess the size and the type of the tumor, taking into account of differential diagnosis. One should also consider the factors indicating spinal instability or the onset of neurological deficits. The criteria developed by Kostiuk-Weinstain and Taneichi are used for that purpose.
The aim of the present study was to evaluate the correspondence between the most essential elements of clinical and MRI examination of the spine and the intraoperative status of patients with spinal tumors.
Materials and Methods: We carried out prospective examination assessing the correspondence between the clinical status and MR images and the intraoperative spine. We introduced algorithm to describe the morphology of neoplastic lesions within the spine.
Results: The information obtained from the clinical examination and the intraoperative status of the spine corresponded with the MRI examination with the exception of the assessment of neoplastic infiltration to soft tissues, dura mater and nerve roots. It was also found that there are no clear-cut MRI features allowing differentiation of metastatic lesions from primary tumors and osteitis. Furthermore, MRI examination does not allow for the assessment of the quality of bone tissue in the vicinity of the tumor.

Keywords:

Magnetic resonance, qualification for spinal surgery, spinal metastases, spine tumors, surgical treatment of the spine.

Affiliation:

Grzegorz Guzik, ul. Dworska 77a, 38-420 Korczyna, Polska.


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