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Korevaar, M.A.N. (author), Heemskerk, J.W.T. (author), Beekman, F.J. (author)
The performance of pinhole single photon emission computed tomography (SPECT) depends on the spatial resolution of the gamma-ray detectors used. Pinhole cameras suffer from strong resolution loss due to the varying depth-of-interaction (DOI) of gamma quanta that enter the detector material at an angle. We eliminate DOI effects in a scintillation...
journal article 2009
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Schaart, D.R. (author), Van Dam, H.T. (author), Seifert, S. (author), Vinke, R. (author), Dendooven, P. (author), Löhner, H. (author), Beekman, F.J. (author)
Silicon photomultipliers (SiPMs) are of great interest to positron emission tomography (PET), as they enable new detector geometries, for e.g., depth-of-interaction (DOI) determination, are MR compatible, and offer faster response and higher gain than other solid-state photosensors such as avalanche photodiodes. Here we present a novel detector...
journal article 2009
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Heemskerk, J.W.T. (author), Korevaar, M.A.N. (author), Kreuger, R. (author), Ligtvoet, C.M. (author), Schotanus, P. (author), Beekman, F.J. (author)
High-resolution imaging of x-ray and gamma-ray distributions can be achieved with cameras that use charge coupled devices (CCDs) for detecting scintillation light flashes. The energy and interaction position of individual gamma photons can be determined by rapid processing of CCD images of individual flashes. Here we investigate the improvement...
journal article 2009
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Maas, M.C. (author), Schaart, D.C. (author), Van der Laan, D.J. (author), Bruyndonckx, P. (author), Lemaître, C. (author), Beekman, F.J. (author), Van Eijk, C.W.E. (author)
We developed positron emission tomography (PET) detectors based on monolithic scintillation crystals and position-sensitive light sensors. Intrinsic depth-of-interaction (DOI) correction is achieved by deriving the entry points of annihilation photons on the front surface of the crystal from the light sensor signals. Here we characterize the...
journal article 2009
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Baiker, M. (author), Vastenhouw, B. (author), Branderhorst, W. (author), Reiber, J.H.C. (author), Beekman, F. (author), Lelieveldt, B.P.F. (author)
Highly focused Micro-SPECT scanners enable the acquisition of functional small animal data with very high-resolution. To acquire a maximum of emitted photons from a specific structure of interest and at the same time minimize the required acquisition time, typically only a small subvolume of the animal is scanned that contains the organs of...
conference paper 2009
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Korevaar, M.A.N. (author), Heemskerk, J.W.T. (author), Goorden, M.C. (author), Beekman, F.J. (author)
Gamma cameras based on charge-coupled devices (CCDs) and micro-columnar CsI scintillators can reach high spatial resolutions. However, the gamma interaction probability of these scintillators is low (typically <30% at 141 keV) due to the limited thickness of presently available micro-columnar scintillators. Continuous scintillators can improve...
journal article 2009
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Van der Have, F. (author), Vastenhouw, B. (author), Ramakers, R.M. (author), Branderhorst, W. (author), Krah, J.O. (author), Ji, C. (author), Staelens, S.G. (author), Beekman, F.J. (author)
We present a new rodent SPECT system (U-SPECT-II) that enables molecular imaging of murine organs down to resolutions of less than half a millimeter and high-resolution total-body imaging. Methods: The U-SPECT-II is based on a triangular stationary detector set-up, an XYZ stage that moves the animal during scanning, and interchangeable cylindric...
journal article 2009
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Baiker, M. (author), Vastenhouw, B. (author), Branderhorst, S.W. (author), Reiber, J.H.C. (author), Beekman, F.J. (author), Lelieveld, B.P.F. (author)
Highly focused Micro-SPECT scanners enable the acquisition of functional small animal data with very high-resolution. To acquire a maximum of emitted photons from a specific structure of interest and at the same time minimize the required acquisition time, typically only a small subvolume of the animal is scanned that contains the organs of...
conference paper 2009
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Wu, C. (author), Vastenhouw, B. (author), Van der Have, F. (author), Dierckx, R.A. (author), Beekman, F.J. (author)
SPECT imaging with low dose or short acquisition time can lead to very noisy reconstructed images. With the USPECT-II system we study the effect of low-count scans, and 3D Gaussian blurring to suppress statistical errors. Three different groups of short-time cardiac rat scans were derived from a longtime scan. Images were reconstructed and then...
conference paper 2008
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Beekman, F.J. (author)
public lecture 2008
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Van der Have, F. (author), Vastenhouw, B. (author), Rentmeester, M. (author), Beekman, F.J. (author)
For multipinhole single-photon emission computed tomography (SPECT), iterative reconstruction algorithms are preferred over analytical methods, because of the often complex multipinhole geometries and the ability of iterative algorithms to compensate for effects like spatially variant sensitivity and resolution. Ideally, such compensation...
journal article 2008
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Beekman, F.J. (author), Kachelriess, M. (author)
journal article 2008
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Jongen, C. (author), De Bruin, K. (author), Beekman, F.J. (author), Booij, J. (author)
Purpose: The dopamine D2 receptor (D2R) is important in the mediation of addiction. [123I]iodobenzamide (IBZM), a SPECT ligand for the D2R, has been used for in vivo studies of D2R availability in humans, monkeys, and rats. Although mouse models are important in the study of addiction, [123I]IBZM has not been used in mice SPECT studies. This...
journal article 2008
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Staelens, S.G. (author), De Wit, T.C. (author), Lemahieu, I.A. (author), Beekman, F.J. (author)
Purpose Thallous (201Tl) chloride is a single-photon emission computed tomography (SPECT) tracer mainly used for assessing perfusion and viability of myocardial tissue. 201Tl emits X-rays around 72 keV and gammas at 167 keV, and has a half-life of 73 h. Regulations allow an intrinsic contamination up to 3–5%, which is mainly caused by 200Tl (368...
journal article 2008
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Beekman, F.J. (author), Hutton, B.F. (author)
Editorial commentary.
journal article 2007
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Beekman, W.J. (author)
doctoral thesis 2000
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Beekman, C. (author), Van den Born, J. (author)
Document(en) uit de collectie Chemische Procestechnologie
report 1991
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Beekman, F.J. (author), Van der Have, F. (author), Vastenhouw, B. (author), Branderhorst, W.J. (author), Van der Linden, A. (author), Smidt, M.P. (author)
We demonstrate new technologies for SPECT imaging with unsurpassed resolution in mice and rats. Results of the imaging of living animals will be shown. In addition development of detectors for next generation systems with an even higher resolution will be shown.
conference paper
Searched for: faculty%3A%22Applied%255C%252BSciences%22
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