TY - JOUR A1 - Boecker, Henning A1 - Kuwert, Torsten A1 - Langen, Karl-J. A1 - Lange, Herwig W. A1 - Czech, Norbert A1 - Ziemons, Karl A1 - Herzog, Hans A1 - Shikare, Shekar A1 - Weindl, Anton A1 - Feinendegen, Ludwig E. T1 - SPECT with HMPAO compared to PET with FDG in Huntington disease JF - Journal of Computer Assisted Tomography Y1 - 1994 SN - 1532-3145 VL - 18 IS - 4 SP - 542 EP - 548 ER - TY - JOUR A1 - Langen, Karl J. A1 - Ziemons, Karl A1 - Kiwit, Jürgen C. W. A1 - Herzog, Hans A1 - Kuwert, Torsten A1 - Bock, Wolfgang A1 - Stöcklin, Gerhard A1 - Feinendegen, Ludwig E. A1 - Müller-Gärtner, Hans-W. T1 - 3-[123I]iodo-α-methyltyrosine and [methyl-11C]-L-methionine uptake in cerebral gliomas: a compara-tive study using SPECT and PET JF - Journal of Nuclear Medicine Y1 - 1997 SN - 0161-5505 VL - 38 IS - 4 SP - 517 EP - 522 ER - TY - JOUR A1 - Weckesser, Matthias A1 - Hufnagel, Andreas A1 - Ziemons, Karl A1 - Grießmeier, Martin A1 - Sonnenberg, Frank A1 - Hackländer, Thomas A1 - Langen, Karl-J. A1 - Holschbach, Markus A1 - Elger, Christian E. A1 - Müller-Gärtner, Hans-W. T1 - Effect of partial volume correction on muscarinic cholinergic receptor imaging with single-photon emission tomography in patients with temporal lobe epilepsy JF - European Journal of Nuclear Medicine N2 - Animal experiments and preliminary results in humans have indicated alterations of hippocampal muscarinic acetylcholine receptors (mAChR) in temporal lobe epilepsy. Patients with temporal lobe epilepsy often present with a reduction in hippocampal volume. The aim of this study was to investigate the influence of hippocampal atrophy on the quantification of mAChR with single photon emission tomography (SPET) in patients with temporal lobe epilepsy. Cerebral uptake of the muscarinic cholinergic antagonist [123I]4-iododexetimide (IDex) was investigated by SPET in patients suffering from temporal lobe epilepsy of unilateral (n=6) or predominantly unilateral (n=1) onset. Regions of interest were drawn on co-registered magnetic resonance images. Hippocampal volume was determined in these regions and was used to correct the SPET results for partial volume effects. A ratio of hippocampal IDex binding on the affected side to that on the unaffected side was used to detect changes in muscarinic cholinergic receptor density. Before partial volume correction a decrease in hippocampal IDex binding on the focus side was found in each patient. After partial volume no convincing differences remained. Our results indicate that the reduction in hippocampal IDex binding in patients with epilepsy is due to a decrease in hippocampal volume rather than to a decrease in receptor concentration. Y1 - 1997 SN - 1619-7089 VL - 24 IS - 9 SP - 1156 EP - 1161 ER - TY - JOUR A1 - Schmidt, Daniela A1 - Langen, Karl-J. A1 - Herzog, Hans A1 - Wirths, Jochen A1 - Holschbach, Markus A1 - Kiwit, Jürgen C. W. A1 - Ziemons, Karl A1 - Coenen, Heinz-H. A1 - Müller-Gärtner, Hans-W. T1 - Whole-body kinetics and dosimetry of L-3[123I]-iodo-α-methyltyrosine JF - European Journal of Nuclear Medicine Y1 - 1997 SN - 1619-7089 VL - 24 IS - 9 SP - 1162 EP - 1166 ER - TY - JOUR A1 - Weckesser, Martin A1 - Grießmeier, Martin A1 - Schmidt, Daniela A1 - Sonnenberg, Frank A1 - Ziemons, Karl A1 - Kemna, Lars A1 - Holschbach, Marcus A1 - Langen, Karl-J. A1 - Müller-Gärtner, Hans-W. T1 - Iodine-123 α-methyl tyrosine single-photon emission tomography of cerebral gliomas: standardised evaluation of tumour uptake and extent JF - European Journal of Nuclear Medicine N2 - Single-photon emission tomography (SPET) with the amino acid analogue l-3-[123I]iodo-α-methyl tyrosine (IMT) is helpful in the diagnosis and monitoring of cerebral gliomas. Radiolabelled amino acids seem to reflect tumour infiltration more specifically than conventional methods like magnetic resonance imaging and computed tomography. Automatic tumour delineation based on maximal tumour uptake may cause an overestimation of mean tumour uptake and an underestimation of tumour extension in tumours with circumscribed peaks. The aim of this study was to develop a program for tumour delineation and calculation of mean tumour uptake which takes into account the mean background activity and is thus optimised to the problem of tumour definition in IMT SPET. Using the frequency distribution of pixel intensities of the tomograms a program was developed which automatically detects a reference brain region and draws an isocontour region around the tumour taking into account mean brain radioactivity. Tumour area and tumour/brain ratios were calculated. A three-compartment phantom was simulated to test the program. The program was applied to IMT SPET studies of 20 patients with cerebral gliomas and was compared to the results of manual analysis by three different investigators. Activity ratios and chamber extension of the phantom were correctly calculated by the automatic analysis. A method based on image maxima alone failed to determine chamber extension correctly. Manual region of interest analysis in patient studies resulted in a mean inter-observer standard deviation of 8.7%±6.1% (range 2.7%–25.0%). The mean value of the results of the manual analysis showed a significant correlation to the results of the automatic analysis (r = 0.91, P<0.0001 for the uptake ratio; r = 0.87, P<0.0001 for the tumour area). We conclude that the algorithm proposed simplifies the calculation of uptake ratios and may be used for observer-independent evaluation of IMT SPET studies. Three-dimensional tumour recognition and transfer to co-registered morphological images based on this program may be useful for the planning of surgical and radiation treatment. Y1 - 1998 SN - 1619-7089 VL - 25 IS - 2 SP - 150 EP - 156 ER - TY - GEN A1 - Achten, Richard A1 - Bauer, Andreas A1 - Bertram, Walter A1 - Cremer, Markus A1 - Daemen, Jos A1 - Dehnhardt, Markus A1 - Fleischer, Manfred A1 - Kirchner, Peter A1 - Leyendecker, Marco A1 - Pietrzyk, Uwe A1 - Schmitz, Jakob A1 - Ziemons, Karl A1 - Zilles, Karl T1 - Vorrichtung zum Halten eines lebenden Objektes bei physiologischen Messungen N2 - Die vorliegende Erfindung betrifft eine Vorrichtung zum Halten eines lebenden Objektes bei physiologischen Messungen mit einem Basiselement und Mitteln zum Arretieren des lebenden Objektes, die atraumatische Ohrenhalter sowie ein Mundstück aufweisen, das mit einer Aussparung für die Zähne des Lebewesens versehen ist, mit einem Masseanteil von wenigstens 95% an glasfaserverstärktem Kunststoff. Y1 - 2005 N1 - Patent Anmelder : Forschungszentrum Jülich GmbH SP - 1 EP - 17 ER - TY - CHAP A1 - Peters, H. A1 - Ziemons, Karl A1 - Dammers, J. A1 - Müller-Veggian, Mattea ED - Nenonen, Jukka T1 - Continuous head motion detection during MEG measurement using head location coils T2 - Proceedings of the 12th International Conference on Biomagnetism : August 13 - 17, 2000, Helsinki University of Technology, Espoo, Finland Y1 - 2001 SN - 951-22-5401-8 N1 - Biomag <12, 2000, Espoo> ; Teknillinen Korkeakoulu ; International Conference on Biomagnetism <12, 2000, Espoo> PB - Helsinki Univ. of Technology, Laboratory of Biomedical Engineering CY - Espoo ER - TY - JOUR A1 - Streun, M. A1 - Chavan, U. A1 - Lame, H. A1 - Parl, C. A1 - Müller-Veggian, Mattea A1 - Ziemons, Karl T1 - Treating the Gain Non-Uniformity of Multi Channel PMTs by Channel-Specific Trigger Levels JF - 2006 IEEE Nuclear Science Symposium Conference Record, Vol. 2. Y1 - 2006 SN - 1082-3654 SP - 1301 EP - 1304 CY - San Diego, CA ER - TY - JOUR A1 - Ziemons, Karl A1 - Achten, R. A1 - Auffray, E. A1 - Müller-Veggian, Mattea T1 - The ClearPET™ neuro scanner: a dedicated LSO/LuYAP phoswich small animal PET scanner JF - 2004 IEEE Nuclear Science Symposium conference record : Nuclear Science Symposium, Medical Imaging Conference ; 16 - 22 October 2004, Rome, Italy ; [including the Symposium on Nuclear Power System (SNPS), 14th Room Temperature Semiconductor X- and Gamma-Ray Detectors Workshop and special focus workshops] / NPSS, Nuclear & Plasma Sciences Society. Guest ed.: J. Anthony Seibert Y1 - 2004 SN - 1082-3654 N1 - Nuclear Science Symposium Conference Record, 2004 IEEE SP - 2430 EP - 2433 PB - IEEE Operations Center CY - Piscataway, NJ ER - TY - JOUR A1 - Ziemons, Karl A1 - Kleines, H. A1 - Erken, I. A1 - Knoben, J. A1 - Zwoll, K. ED - Lehmann, Thomas T1 - IME-DV Projekt: M-FIRBe, Multi-Modality Functional Imaging for Brain Research JF - Bildverarbeitung für die Medizin : Algorithmen - Systeme - Anwendungen Y1 - 1997 SN - 3-86073-519-5 N1 - Proceedings des Aachener Workshops am 8. u. 9. November 1996 ; WG_005 Arbeitsgruppenvorstellungen SP - 363 EP - 366 PB - Verl. der. Augustinus-Buchh. CY - Aachen ER - TY - JOUR A1 - Kleines, H. A1 - Erki, I. A1 - Ziemons, Karl A1 - Zwoll, K. ED - Lehmann, Thomas T1 - ATM- und Multimedia Pilotsystem im Rahmen des Projektes M-FIBRe Aufbau und Erfahrungen JF - Bildverarbeitung für die Medizin : Algorithmen - Systeme - Anwendungen Y1 - 1997 SN - 3-86073-519-5 N1 - Proceedings des Aachener Workshops am 8. u. 9. November 1996 ; PP_001 Posterpräsentation SP - 241 EP - 248 PB - Verl. der. Augustinus-Buchh. CY - Aachen ER - TY - JOUR A1 - Erki, I. A1 - Kleines, H. A1 - Ziemons, Karl A1 - Zwoll, K. ED - Lehmann, Thomas T1 - Interaktives System zur Darstellung funktionaler Bilddaten JF - Bildverarbeitung für die Medizin : Algorithmen - Systeme - Anwendungen Y1 - 1997 SN - 3-86073-519-5 N1 - Proceedings des Aachener Workshops am 8. u. 9. November 1996 ; PP_002 Posterpräsentation SP - 249 EP - 254 PB - Verl. der. Augustinus-Buchh. CY - Aachen ER - TY - JOUR A1 - Grießmeier, M. A1 - Sonnenberg, F. A1 - Weckesser, M. A1 - Ziemons, Karl A1 - Langen, K.-J. A1 - Müller-Gärtner, H. W. T1 - Improvement of SPECT quantification in small brain structures by using experiment based recovery-coefficient corrections JF - European Journal of Nuclear Medicine Y1 - 1996 SN - 1619-7089 N1 - Abstracts ; PSu827 VL - 23 IS - 9 SP - 1238 EP - 1238 ER - TY - JOUR A1 - Kleines, H. A1 - Ziemons, Karl A1 - Zwoll, K. T1 - Experiences with ATM in a multivendor pilot system at Forschungszentrum Jülich JF - IEEE Transactions on Nuclear Science N2 - The ATM technology for high speed serial transmission provides a new quality of communication by introducing novel features in a LAN environment, especially support of real time communication, of both LAN and WAN communication and of multimedia streams. In order to evaluate ATM for future DAQ systems and remote control systems as well as for a high speed picture archiving and communications system for medical images, Forschungszentrum Julich has build up a pilot system for the evaluation of ATM and standard low cost multimedia systems. It is a heterogeneous multivendor system containing a variety of switches and desktop solutions, employing different protocol options of ATM. The tests conducted in the pilot system revealed major difficulties regarding stability, interoperability and performance. The paper presents motivations, layout and results of the pilot system. Discussion of results concentrates on performance issues relevant for realistic applications, e.g., connection to a RAID system via NFS over ATM Y1 - 1998 SN - 0018-9499 VL - 45 IS - 4 SP - 1867 EP - 1871 ER - TY - JOUR A1 - Taylor, J. G. A1 - Schmitz, N. A1 - Ziemons, Karl A1 - Grosse-Ruyken, M.-L. A1 - Gruber, O. A1 - Müller-Gärtner, H.-W. A1 - Shah, N. J. T1 - The network of brain areas involved in the motion aftereffect JF - Neuroimage N2 - A network of brain areas is expected to be involved in supporting the motion aftereffect. The most active components of this network were determined by means of an fMRI study of nine subjects exposed to a visual stimulus of moving bars producing the effect. Across the subjects, common areas were identified during various stages of the effect, as well as networks of areas specific to a single stage. In addition to the well-known motion-sensitive area MT the prefrontal brain areas BA44 and 47 and the cingulate gyrus, as well as posterior sites such as BA37 and BA40, were important components during the period of the motion aftereffect experience. They appear to be involved in control circuitry for selecting which of a number of processing styles is appropriate. The experimental fMRI results of the activation levels and their time courses for the various areas are explored. Correlation analysis shows that there are effectively two separate and weakly coupled networks involved in the total process. Implications of the results for awareness of the effect itself are briefly considered in the final discussion. Y1 - 2000 SN - 1053-8119 VL - 11 IS - 4 SP - 257 EP - 270 ER - TY - JOUR A1 - Fink, G. R. A1 - Marshall, J. C. A1 - Shah, N. J. A1 - Weiss, P.H. A1 - Halligan, P. W. A1 - Grosse-Ruyken, M. A1 - Ziemons, Karl A1 - Zilles, K. A1 - Freund, H. J. T1 - Line bisection judgments implicate right parietal cortex and cerebellum as assessed by fMRI JF - Neurology Y1 - 2000 SN - 1526-632X VL - 54 IS - 6 SP - 1324 EP - 1331 ER - TY - JOUR A1 - Bussmann, N. A1 - Engels, R. A1 - Fuss, L. A1 - Kemmerling, G. A1 - Reinartz, R. A1 - Langen, K.-J. A1 - Schelten, J. A1 - Ziemons, Karl T1 - Performance measurement of a new high resolution detector system for I-131 thyroid studies JF - 2000 IEEE Nuclear Science Symposium Conference Record, Vol. 3 N2 - A 2-dimensional detector system for high resolution thyroid I-131 scintigraphy was developed. It has a sensitive area of 4 cm×4 cm and consists of a lead-collimator and an array of 10×10 EGO crystals combined with a position sensitive photomultiplier. The spatial resolution and the sensitivity of the detector has been measured and compared to two commercially available gamma-cameras. Furthermore first patient measurements have been carried out Y1 - 2000 SN - 1082-3654 SP - 22/35 EP - 22/37 ER - TY - JOUR A1 - Streun, M. A1 - Brandenburg, G. A1 - Larue, H. A1 - Zimmermann, E. A1 - Ziemons, Karl A1 - Halling, H. T1 - Pulse recording by free-running sampling JF - 2000 IEEE Nuclear Science Symposium Conference Record, Vol. 2 N2 - Pulses from a position-sensitive photomultiplier (PS-PMT) are recorded by free running ADCs at a sampling rate of 40 MHz. A four-channel acquisition-board has been developed which is equipped with four 12 bit-ADCs connected to one FPGA (field programmable gate array). The FPGA manages data acquisition and the transfer to the host computer. It can also work as a digital trigger, so a separate hardware-trigger can be omitted. The method of free running sampling provides a maximum of information, besides the pulse charge and amplitude also pulse shape and starting time are contained in the sampled data. These informations are crucial for many tasks such as distinguishing between different scintillator materials, determination of radiation type, pile-up recovery, coincidence detection or time-of-flight applications. The absence of an analog integrator allows coping with very high count rates. Since this method is going to be employed in positron emission tomography (PET), the position of an event is another important information. The simultaneous readout of four channels allows localization by means of center-of-gravity weighting. First results from a test setup with LSO-scintillators coupled to the PS-PMT are presented Y1 - 2000 SN - 1082-3654 SP - 9/179 EP - 9/181 ER - TY - JOUR A1 - Hautzel, H. A1 - Taylor, J. G. A1 - Krause, B. J. A1 - Schmitz, N. A1 - Tellmann, L. A1 - Ziemons, Karl A1 - Shah, N. J. A1 - Herzog, H. A1 - Müller-Gärtner, H.-W. T1 - The motion aftereffect: more than area V5/MT? Evidence from 15O-butanol PET studies JF - Brain Research N2 - The motion aftereffect is a perceptual phenomenon which has been extensively investigated both psychologically and physiologically. Neuroimaging techniques have recently demonstrated that area V5/MT is activated during the perception of this illusion. The aim of this study was to test the hypothesis if a more broadly distributed network of brain regions subserves the motion aftereffect. To identify the neuronal structures involved in the perception of the motion aftereffect, regional cerebral blood flow (rCBF) measurements with positron emission tomography were performed in six normal volunteers. Data were analysed using SPM96. The motion-sensitive visual areas including area V5/MT were activated in both hemispheres. Additionally, the lateral parietal cortex bilaterally, the right dorsolateral prefrontal cortex, the anterior cingulate cortex and the left cerebellum showed significant increases in rCBF values during the experience of the waterfall illusion. In a further reference condition with identical attentional demand but no perception of a motion aftereffect elevated rCBF were found in these regions as well. In conclusion, our findings support the notion that the perceptual illusion of motion arises exclusively in the motion-sensitive visual area V5/MT. In addition, a more widespread network of brain regions including the prefrontal and parietal cortex is activated during the waterfall illusion which represents a non-motion aftereffect-specific subset of brain areas but is involved in more basic attentional processing and cognition. Y1 - 2001 SN - 0006-8993 VL - 892 IS - 2 SP - 281 EP - 292 ER - TY - JOUR A1 - Streun, M. A1 - Brandenburg, G. A1 - Larue, H. A1 - Zimmermann, E. A1 - Ziemons, Karl A1 - Halling, H. T1 - Pulse recording by free-running sampling JF - IEEE Transactions on Nuclear Science N2 - Pulses from a position-sensitive photomultiplier (PS-PMT) are recorded by free-running ADCs at a sampling rate of 40 MHz. A four-channel acquisition board has been developed which is equipped with four 12-bit ADCs connected to one field programmable gate array (FPGA). The FPGA manages data acquisition and the transfer to the host computer. It can also work as a digital trigger, so a separate hardware trigger can be omitted. The method of free-running sampling provides a maximum of information, besides the pulse charge and amplitude also pulse shape and starting time are contained in the sampled data. This information is crucial for many tasks such as distinguishing between different scintillator materials, determination of radiation type, pile-up recovery, coincidence detection or time-of-flight applications. The absence of an analog integrator allows very high count rates to be dealt with. Since this method is to be employed in positron emission tomography (PET), the position of an event is also important. The simultaneous readout of four channels allows localization by means of center-of-gravity weighting. First results from a test setup with LSO scintillators coupled to the PS-PMT are presented here Y1 - 2001 SN - 0018-9499 VL - 48 IS - 3 SP - 524 EP - 526 ER -