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See detail188Re and 68Ga radiolabeled Starch-Based Microparticles as potential theranostic radiopharmaceutical for Hepatocellular Carcinoma
Verger, Elise ULg; Drion, Pierre ULg; MEFFRE, Geneviève ULg et al

in Journal of Nuclear Medicine (The) (2016, May 01), 57(suppl. 2),

The SBMP as a unique vector is a promising theranostic agent for the SIRT of HCC.

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See detailMicroparticules à base d’amidon radiomarquées au 188Re et 68Ga comme agent théranostique pour la radiothérapie interne sélective du carcinome hépatocellulaire
Verger, Elise ULg; Drion, Pierre ULg; MEFFRE, Geneviève ULg et al

in 2es Journées Francophones de Médecine Nucléaire (2016, May), 40(3), 182

Les microparticules SBMP, en étant capable d'être radiomarquées rapidement, de manière reproductible, sous forme de kits prêt-à-l‘emploi, par du 188Re et du 68Ga, se révèlent être un outil théranostique ... [more ▼]

Les microparticules SBMP, en étant capable d'être radiomarquées rapidement, de manière reproductible, sous forme de kits prêt-à-l‘emploi, par du 188Re et du 68Ga, se révèlent être un outil théranostique prometteur pour le traitement du carcinome hépatocellulaire. [less ▲]

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See detailFDG PET/CT texture analysis for predicting the outcome of lung cancer treated by stereotactic body radiation therapy.
LOVINFOSSE, Pierre ULg; Janvary, Zsolt Levente; COUCKE, Philippe ULg et al

in European journal of nuclear medicine and molecular imaging (2016)

INTRODUCTION: With 18F-FDG PET/CT, tumor uptake intensity and heterogeneity have been associated with outcome in several cancers. This study aimed at investigating whether 18F-FDG uptake intensity, volume ... [more ▼]

INTRODUCTION: With 18F-FDG PET/CT, tumor uptake intensity and heterogeneity have been associated with outcome in several cancers. This study aimed at investigating whether 18F-FDG uptake intensity, volume or heterogeneity could predict the outcome in patients with non-small cell lung cancers (NSCLC) treated by stereotactic body radiation therapy (SBRT). METHODS: Sixty-three patients with NSCLC treated by SBRT underwent a 18F-FDG PET/CT before treatment. Maximum and mean standard uptake value (SUVmax and SUVmean), metabolic tumoral volume (MTV), total lesion glycolysis (TLG), as well as 13 global, local and regional textural features were analysed. The predictive value of these parameters, along with clinical features, was assessed using univariate and multivariate analysis for overall survival (OS), disease-specific survival (DSS) and disease-free survival (DFS). Cutoff values were obtained using logistic regression analysis, and survivals were compared using Kaplan-Meier analysis. RESULTS: The median follow-up period was 27.1 months for the entire cohort and 32.1 months for the surviving patients. At the end of the study, 25 patients had local and/or distant recurrence including 12 who died because of the cancer progression. None of the clinical variables was predictive of the outcome, except age, which was associated with DFS (HR 1.1, P = 0.002). None of the 18F-FDG PET/CT or clinical parameters, except gender, were associated with OS. The univariate analysis showed that only dissimilarity (D) was associated with DSS (HR = 0.822, P = 0.037), and that several metabolic measurements were associated with DFS. In multivariate analysis, only dissimilarity was significantly associated with DSS (HR = 0.822, P = 0.037) and with DFS (HR = 0.834, P < 0.01). CONCLUSION: The textural feature dissimilarity measured on the baseline 18F-FDG PET/CT appears to be a strong independent predictor of the outcome in patients with NSCLC treated by SBRT. This may help selecting patients who may benefit from closer monitoring and therapeutic optimization. [less ▲]

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See detailRecovery of language comprehension in the minimally conscious state studied by FDG-PET
Wannez, Sarah ULg; Thibaut, Aurore ULg; Vitali-Roscini, Gaia et al

Poster (2015, June 21)

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See detailBiodistribution and radiation dosimetry for the novel SV2A radiotracer [18F]UCB-H: First-in-human study.
Bretin, Florian ULg; Bahri, Mohamed Ali ULg; BERNARD, Claire ULg et al

in Molecular Imaging & Biology (2015), 17

Abstract- [18F]UCB-H is a novel radiotracer with a high affinity for SV2A, a protein expressed in synaptic vesicles. SV2A is the binding site of levetiracetam, a “first in class” antiepileptic drug with a ... [more ▼]

Abstract- [18F]UCB-H is a novel radiotracer with a high affinity for SV2A, a protein expressed in synaptic vesicles. SV2A is the binding site of levetiracetam, a “first in class” antiepileptic drug with a distinct but still poorly understood mechanism of action. The objective of this study was to determine the biodistribution and radiation dosimetry of [18F]UCB-H in a human clinical trial and to establish injection limits according to biomedical research guidelines. Additionally, the clinical radiation dosimetry results were compared to estimations in previously published preclinical data. Dynamic whole body PET/CT imaging was performed over approximately 110 minutes on five healthy male volunteers after injection of 144.5 ± 7.1 MBq (range, 139.1 – 156.5 MBq) of [18F]UCB-H. Major organs were delineated on CT images and time-activity curves were obtained from co-registered dynamic PET emission scans. Time-integrated activity coefficients were calculated as area under the curve using trapezoidal numerical integration. Urinary excretion data based on PET-activities including voiding was simulated using the dynamic bladder module of OLINDA/EXM. The radiation dosimetry was calculated using OLINDA/EXM. The effective dose to the OLINDA/EXM 70 kg standard male was 1.54E-02 ± 6.84E-04 mSv/MBq, with urinary bladder wall, gallbladder wall and the liver receiving the highest absorbed dose. The brain, the tracer’s main organ of interest, received an absorbed dose of 1.89E-02 ± 2.32E-03 mGy/MBq. This first human dosimetry study of [18F]UCB-H indicated that the tracer shows similar radiation burdens to widely used common clinical tracers. Single injections of at maximum 672 MBq for USA practice and 649 MBq for European practice keep radiation exposure below recommended limits. Recently published preclinical dosimetry data extrapolated from mice provided satisfactory prediction of total body and effective dose, but showed significant differences in organ absorbed doses compared to human data. [less ▲]

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See detailClinical Response to tDCS Depends on Residual Brain Metabolism and Grey Matter Integrity in Patients With Minimally Conscious State.
Thibaut, Aurore ULg; Di Perri, Carol; Chatelle, Camille ULg et al

in Brain stimulation (2015), 8(6), 1116-23

BACKGROUND: Transcranial direct current stimulation (tDCS) was recently shown to promote recovery of voluntary signs of consciousness in some patients in minimally conscious state (MCS). However, it ... [more ▼]

BACKGROUND: Transcranial direct current stimulation (tDCS) was recently shown to promote recovery of voluntary signs of consciousness in some patients in minimally conscious state (MCS). However, it remains unclear why clinical improvement is only observed in a subgroup of patients. OBJECTIVES: In this retrospective study, we investigated the relationship between tDCS responsiveness and neuroimaging data from MCS patients. METHODS: Structural Magnetic Resonance Imaging (MRI), Fluorodeoxyglucose Positron emission tomography (FDG-PET) and clinical electroencephalography (EEG) were acquired in 21 sub-acute and chronic MCS patients (8 tDCS responders) who subsequently (<48 h) received left dorsolateral prefrontal (DLPF) tDCS in a double-blind randomized cross-over trial. The behavioral data have been published elsewhere (Thibaut et al., Neurology, 2014). RESULTS: Grey matter atrophy was observed in non-responders as compared with responders in the left DLPF cortex, the medial-prefrontal cortex, the cingulate cortex, the hippocampi, part of the rolandic regions, and the left thalamus. FDG-PET showed hypometabolism in non-responders as compared with responders in the left DLPF cortex, the medial-prefrontal cortex, the precuneus, and the thalamus. EEG did not show any difference between the two groups. CONCLUSION: Our findings suggest that the transient increase of signs of consciousness following left DLPF tDCS in patients in MCS require grey matter preservation and residual metabolic activity in cortical and subcortical brain areas known to be involved in attention and working memory. These results further underline the critical role of long-range cortico-thalamic connections in consciousness recovery, providing important information for guidelines on the use of tDCS in disorders of consciousness. [less ▲]

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See detailQuantitative rates of brain glucose metabolism distinguish minimally conscious from vegetative state patients.
Stender, Johan; Kupers, Ron; Rodell, Anders et al

in Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism (2015), 35(1), 58-65

The differentiation of the vegetative or unresponsive wakefulness syndrome (VS/UWS) from the minimally conscious state (MCS) is an important clinical issue. The cerebral metabolic rate of glucose (CMRglc ... [more ▼]

The differentiation of the vegetative or unresponsive wakefulness syndrome (VS/UWS) from the minimally conscious state (MCS) is an important clinical issue. The cerebral metabolic rate of glucose (CMRglc) declines when consciousness is lost, and may reveal the residual cognitive function of these patients. However, no quantitative comparisons of cerebral glucose metabolism in VS/UWS and MCS have yet been reported. We calculated the regional and whole-brain CMRglc of 41 patients in the states of VS/UWS (n=14), MCS (n=21) or emergence from MCS (EMCS, n=6), and healthy volunteers (n=29). Global cortical CMRglc in VS/UWS and MCS averaged 42% and 55% of normal, respectively. Differences between VS/UWS and MCS were most pronounced in the frontoparietal cortex, at 42% and 60% of normal. In brainstem and thalamus, metabolism declined equally in the two conditions. In EMCS, metabolic rates were indistinguishable from those of MCS. Ordinal logistic regression predicted that patients are likely to emerge into MCS at CMRglc above 45% of normal. Receiver-operating characteristics showed that patients in MCS and VS/UWS can be differentiated with 82% accuracy, based on cortical metabolism. Together these results reveal a significant correlation between whole-brain energy metabolism and level of consciousness, suggesting that quantitative values of CMRglc reveal consciousness in severely brain-injured patients. [less ▲]

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See detailPitfalls and Limitations of PET/CT in Brain Imaging.
Salmon, Eric ULg; Bernard, Claire ULg; HUSTINX, Roland ULg

in Seminars in nuclear medicine (2015), 45(6), 541-51

Neurologic applications were at the forefront of PET imaging when the technique was developed in the mid-1970s. Although oncologic indications have become prominent in terms of number of studies performed ... [more ▼]

Neurologic applications were at the forefront of PET imaging when the technique was developed in the mid-1970s. Although oncologic indications have become prominent in terms of number of studies performed worldwide, neurology remains a major field in which functional imaging provides unique information, both for clinical and research purposes. The evaluation of glucose metabolism using FDG remains the most frequent exploration, but in recent years, alternative radiotracers have been developed, including fluorinated amino acid analogues for primary brain tumor imaging and fluorinated compounds for assessing the amyloid deposits in patients with suspected Alzheimer disease. As the brain is enclosed in the skull, which presents fixed landmarks, it is relatively easy to coregister images obtained with various cross-sectional imaging methods, either functional or anatomical, with a relatively high accuracy and robustness. Nevertheless, PET in neurology has fully benefited from the advent of hybrid imaging. Attenuation and scatter correction is now much faster and equally accurate, using CT as compared with the traditional transmission scan using an external radioactive source. The perfect coregistration with the CT data, which is now systematically performed, also provides its own set of valuable information, for instance regarding cerebral atrophy. However, hybrid imaging in neurology comes with pitfalls and limitations, in addition to those that are well known, for example, blood glucose levels or psychotropic drugs that greatly affect the physiological FDG uptake. Movements of the patient's head, either during the PET acquisition or between the PET and the CT acquisitions will generate artifacts that may be very subtle yet lead to erroneous interpretation of the study. Similarly, quantitative analysis, such as voxel-based analyses, may prove very helpful in improving the diagnostic accuracy and the reproducibility of the reading, but a wide variety of artifacts may also be introduced, and should therefore be identified and corrected. [less ▲]

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See detailChanges in cerebral metabolism in patients with a minimally conscious state responding to zolpidem.
Chatelle, Camille ULg; Thibaut, Aurore ULg; Gosseries, Olivia ULg et al

in Frontiers in Neuroscience (2014)

BACKGROUND: Zolpidem, a short-acting non-benzodiazepine GABA agonist hypnotic, has been shown to induce paradoxical responses in some patients with disorders of consciousness (DOC), leading to recovery of ... [more ▼]

BACKGROUND: Zolpidem, a short-acting non-benzodiazepine GABA agonist hypnotic, has been shown to induce paradoxical responses in some patients with disorders of consciousness (DOC), leading to recovery of arousal and cognitive abilities. We here assessed zolpidem-induced changes in regional brain metabolism in three patients with known zolpidem response in chronic post-anoxic minimally conscious state (MCS). METHODS: [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) and standardized clinical assessments using the Coma Recovery Scale-Revised were performed after administration of 10 mg zolpidem or placebo in a randomized double blind 2-day protocol. PET data preprocessing and comparison with a healthy age-matched control group were performed using statistical parametric mapping (SPM8). RESULTS: Behaviorally, all patients recovered functional communication after administration of zolpidem (i.e., emergence from the MCS). FDG-PET showed increased metabolism in dorsolateral prefrontal and mesiofrontal cortices after zolpidem but not after placebo administration. CONCLUSION: Our data show a metabolic activation of prefrontal areas, corroborating the proposed mesocircuit hypothesis to explain the paradoxical effect of zolpidem observed in some patients with DOC. It also suggests the key role of the prefrontal cortices in the recovery of functional communication and object use in hypoxic patients with chronic MCS. [less ▲]

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See detailNociception coma scale-revised scores correlate with metabolism in the anterior cingulate cortex.
Chatelle, Camille ULg; Thibaut, Aurore ULg; Bruno, Marie-Aurelie et al

in Neurorehabilitation and neural repair (2014), 28(2), 149-52

BACKGROUND: . The Nociception Coma Scale-Revised (NCS-R) was recently validated to assess possible pain perception in patients with disorders of consciousness. OBJECTIVE: . To identify correlations ... [more ▼]

BACKGROUND: . The Nociception Coma Scale-Revised (NCS-R) was recently validated to assess possible pain perception in patients with disorders of consciousness. OBJECTIVE: . To identify correlations between cerebral glucose metabolism and NCS-R total scores. METHODS: . [18F]-fluorodeoxyglucose positron emission tomography, NCS-R, and Coma Recovery Scale-Revised assessments were performed in 49 patients with disorders of consciousness. RESULTS: . We identified a significant positive correlation between NCS-R total scores and metabolism in the posterior part of the anterior cingulate cortex, known to be involved in pain processing. No other cluster reached significance. No significant effect of clinical diagnosis (vegetative/unresponsive vs minimally conscious states), etiology or interval since insult was observed. CONCLUSIONS: . Our data support the hypothesis that the NCS-R total scores are related to cortical processing of nociception and may constitute an appropriate behavioral tool to assess, monitor, and treat possible pain in brain-damaged noncommunicative patients with disorders of consciousness. Future studies using event-related functional magnetic resonance imaging should investigate the correlation between NCS-R scores and brain activation in response to noxious stimulation at the single-subject level. [less ▲]

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See detailQuantitative rates of brain glucose metabolism distinguish minimally conscious from vegetative state patients
Stender, Johan; Kupers, Ron; Rodell, Anders et al

in Journal of Cerebral Blood Flow & Metabolism (2014)

The differentiation of the vegetative or unresponsive wakefulness syndrome (VS/UWS) from the minimally conscious state (MCS) is an important clinical issue. The cerebral metabolic rate of glucose (CMRglc ... [more ▼]

The differentiation of the vegetative or unresponsive wakefulness syndrome (VS/UWS) from the minimally conscious state (MCS) is an important clinical issue. The cerebral metabolic rate of glucose (CMRglc) declines when consciousness is lost, and may reveal the residual cognitive function of these patients. However, no quantitative comparisons of cerebral glucose metabolism in VS/UWS and MCS have yet been reported. We calculated the regional and whole-brain CMRglc of 41 patients in the states of VS/UWS (n = 14), MCS (n = 21) or emergence from MCS (EMCS, n = 6), and healthy volunteers (n = 29). Global cortical CMRglc in VS/UWS and MCS averaged 42% and 55% of normal, respectively. Differences between VS/UWS and MCS were most pronounced in the frontoparietal cortex, at 42% and 60% of normal. In brainstem and thalamus, metabolism declined equally in the two conditions. In EMCS, metabolic rates were indistinguishable from those of MCS. Ordinal logistic regression predicted that patients are likely to emerge into MCS at CMRglc above 45% of normal. Receiver-operating characteristics showed that patients in MCS and VS/UWS can be differentiated with 82% accuracy, based on cortical metabolism. Together these results reveal a significant correlation between whole-brain energy metabolism and level of consciousness, suggesting that quantitative values of CMRglc reveal consciousness in severely brain-injured patients. [less ▲]

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See detailPositron emission tomography imaging in altered states of consciousness: Coma, sleep and hypnosis
Thibaut, Aurore ULg; Chatelle, Camille ULg; Stender, Johan et al

in Dierckx, Rudi; Otte, Andreas; Vries, Erik (Eds.) et al PET and SPECT in Neurology (2014)

Positron emission tomography (PET) allows studies of cerebral metabolism and blood flow and has been widely used to investigate physiological mechanisms underlying altered states of consciousness. The aim ... [more ▼]

Positron emission tomography (PET) allows studies of cerebral metabolism and blood flow and has been widely used to investigate physiological mechanisms underlying altered states of consciousness. The aim of this chapter is to review the current literature on brain metabolism during physiological or pathological loss of consciousness including studies on disorders of consciousness arising from severe brain injury (vegetative/unresponsive or minimally conscious states), and related non-pathological conditions such as sleep and hypnotic states. Identifying brain areas specifically involved in conscious processing, these studies have contributed to our understanding of the underlying physiology of consciousness. The precuneal and cingulate cortices, for example, seem to be key areas for maintaining consciousness awareness. Other areas such as hypothalamus, amygdala or the temporo-occipital cortex seem to play a role in different states of unconsciousness such as rapid eye movement sleep and hypnosis. PET studies permit a better comprehension of the loss of consciousness, and focus the implication of specific neural areas and networks in pathologically (vegetative/unresponsive or minimally conscious states), physiologically (sleep), and hypnotically altered states of consciousness. [less ▲]

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See detailFDG PET/CT for rectal carcinoma radiotherapy treatment planning : Comparison of functional volume delineation algorithms and clinical challenges.
WITHOFS, Nadia ULg; BERNARD, Claire ULg; VAN DER REST, Catherine ULg et al

in Journal of Applied Clinical Medical Physics (2014), 15(5), 216-228

PET/CT imaging could improve delineation of rectal carcinoma gross tumor volume (GTV) and reduce interobserver variability. The objective of this work was to compare various functional volume delineation ... [more ▼]

PET/CT imaging could improve delineation of rectal carcinoma gross tumor volume (GTV) and reduce interobserver variability. The objective of this work was to compare various functional volume delineation algorythms. [less ▲]

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See detailLesion size effect on variability in PET quantification in multicenter trials
Guiot, Thomas; Vanderlinden, Bruno; Seret, Alain ULg et al

Poster (2013, May 25)

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See detailBrain dead yet mind alive: A positron emission tomography case study of brain metabolism in Cotard’s syndrome
Charland-Verville, Vanessa ULg; Bruno, Marie-Aurélie ULg; Bahri, Mohamed Ali ULg et al

in Cortex : A Journal Devoted to the Study of the Nervous System & Behavior (2013), 49(7), 1997-1999

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See detailOrthanc - A lightweight, RESTful DICOM server for healthcare and medical research
JODOGNE, Sébastien ULg; Bernard, Claire ULg; DEVILLERS, Magali ULg et al

in Proceedings, IEEE International Symposium on Biomedical Imaging: from Nano to Macro (2013, April)

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See detailAutomated platform for the quality control of PET-CT scanners following AFCN/FANC recommendations
Bernard, Claire ULg; Paulus, Cyril; JODOGNE, Sébastien ULg et al

in Proceedings of the Belgian Hospital Physicists Association Symposium (2013, February)

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See detail(111)Indium-oxine labelling for evaluating the homing process of autologous osteoblasts implanted percutaneously in atrophic nonunion fractures.
Hauzeur, Jean-Philippe; Bernard, Claire ULg; Egrise, Dominique et al

in International Orthopaedics (2013), 37(1), 131-6

PURPOSE: The aim of the study was to control the in vivo localisation of implanted cells in cell-based therapies. Labelling cells with (111)indium-oxine is one of the most interesting methods proposed. We ... [more ▼]

PURPOSE: The aim of the study was to control the in vivo localisation of implanted cells in cell-based therapies. Labelling cells with (111)indium-oxine is one of the most interesting methods proposed. We evaluated this method in the setting of autologous osteoblast implantation in nonunion fractures. METHODS: An in vitro study of osteoblasts was conducted after (111)indium-oxine labelling. Radioactivity retention and viability, proliferation and the ability to produce alkaline phosphatase were evaluated in a seven-day culture. In vivo labelling of implanted osteoblastic cells was conducted during a therapeutic trial of atrophic nonunion fractures, with the leakage outside the nonunion site and local uptake evolution at four, 24 and 48 hour being studied. RESULTS: The mean labelling efficiency for osteoprogenitors was 78.8 +/- 4.6 %. The intracellular retention was 89.4 +/- 2.1 % at three hours and 67.3 +/- 4.7 % at 18 hours. The viability assessed at three hours was 93.7 +/- 0.6 %. After seven days of culture, morphology and alkaline phosphatase staining were similar for both labelled and unlabelled control cells, although the proliferation rate was decreased in the labelled cells. Some local intraosseous leakage was observed in four of 17 cases. All patients showed uptake at the injection site, with four having no other uptake. Four patients showed additional uptake in the bladder, liver and spleen, while 11 patients had additional uptake in the lungs in addition to the bladder, liver and spleen. The activity ratios (injection site/body) were 48 +/- 28 % at four hours, 40 +/- 25 % at 24 hours and 35 +/- 25 % at 48 hours. After correcting for decay, the activity within the injection site was 82 +/- 15 % at 24 hours and 69 +/- 11 % at 48 hours compared with the activity measured at four hours. No relationship was found between uptake and radiological bone repair. CONCLUSIONS: The (111)indium-oxine labelling appears to be a good method for monitoring the behaviour of the osteoblastic cells after their implantation in atrophic nonunion fractures. [less ▲]

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See detailQuantitative capabilities of four state-of-the-art SPECT-CT cameras
Seret, Alain ULg; Nguyen, Daniel ULg; BERNARD, Claire ULg

in European Journal of Nuclear Medicine and Molecular Imaging Research (2012), 2

Background. Four state-of-the-art single-photon emission computed tomography-computed tomography (SPECT-CT) systems, namely Philips Brightview, General Electric Discovery NM/CT 670 and Infinia Hawkeye 4 ... [more ▼]

Background. Four state-of-the-art single-photon emission computed tomography-computed tomography (SPECT-CT) systems, namely Philips Brightview, General Electric Discovery NM/CT 670 and Infinia Hawkeye 4, and Siemens Symbia T6, were investigated in terms of accuracy of attenuation and scatter correction, contrast recovery for small hot and cold structures, and quantitative capabilities when using their dedicated three-dimensional iterative reconstruction with attenuation and scatter corrections and resolution recovery. Methods. The National Electrical Manufacturers Association (NEMA) NU-2 1994 phantom with cold air, water, and Teflon inserts, and a homemade contrast phantom with hot and cold rods were filled with 99mTc and scanned. The acquisition parameters were chosen to provide adequate linear and angular sampling and high count statistics. The data were reconstructed using Philips Astonish, General Electric Evolution for Bone, or Siemens Flash3D, eight subsets, and a varying number of iterations. A procedure similar to the one used in positron emission tomography (PET) allowed us to obtain the factor to convert counts per pixel into activity per unit volume. Results. Edge and oscillation artifacts were observed with all phantoms and all systems. At 30 iterations, the residual fraction in the inserts of the NEMA phantom fell below 3.5%. Contrast recovery increased with the number of iterations but became almost saturated at 24 iterations onwards. In the uniform part of the NEMA and contrast phantoms, a quantification error below 10% was achieved. Conclusions. In objects whose dimensions exceeded the SPECT spatial resolution by several times, quantification seemed to be feasible within 10% error limits. A partial volume effect correction strategy remains necessary for the smallest structures. The reconstruction artifacts nevertheless remain a handicap on the road towards accurate quantification in SPECT and should be the focus of further works in reconstruction tomography. [less ▲]

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