Positron emission tomography imaging in altered states of consciousness: Coma, sleep and hypnosis
Thibaut, Aurore ; Chatelle, Camille ; 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 ▲]Detailed reference viewed: 27 (6 ULg)
FDG PET/CT for rectal carcinoma radiotherapy treatment planning : Comparison of functional volume delineation algorithms and clinical challenges.
WITHOFS, Nadia ; BERNARD, Claire ; VAN DER REST, Catherine 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 ▲]Detailed reference viewed: 41 (18 ULg)
SPECT/CT workflow and imaging protocols.
; Hustinx, Roland
in European journal of nuclear medicine and molecular imaging (2014), 41
PURPOSE: Introducing a hybrid imaging method such as single photon emission computed tomography (SPECT)/CT greatly alters the routine in the nuclear medicine department. It requires designing new workflow ... [more ▼]
PURPOSE: Introducing a hybrid imaging method such as single photon emission computed tomography (SPECT)/CT greatly alters the routine in the nuclear medicine department. It requires designing new workflow processes and the revision of original scheduling process and imaging protocols. In addition, the imaging protocol should be adapted for each individual patient, so that performing CT is fully justified and the CT procedure is fully tailored to address the clinical issue. Such refinements often occur before the procedure is started but may be required at some intermediate stage of the procedure. Furthermore, SPECT/CT leads in many instances to a new partnership with the radiology department. This article presents practical advice and highlights the key clinical elements which need to be considered to help understand the workflow process of SPECT/CT and optimise imaging protocols. METHODS: The workflow process using SPECT/CT is complex in particular because of its bimodal character, the large spectrum of stakeholders, the multiplicity of their activities at various time points and the need for real-time decision-making. RESULTS: With help from analytical tools developed for quality assessment, the workflow process using SPECT/CT may be separated into related, but independent steps, each with its specific human and material resources to use as inputs or outputs. This helps identify factors that could contribute to failure in routine clinical practice. At each step of the process, practical aspects to optimise imaging procedure and protocols are developed. A decision-making algorithm for justifying each CT indication as well as the appropriateness of each CT protocol is the cornerstone of routine clinical practice using SPECT/CT. CONCLUSION: In conclusion, implementing hybrid SPECT/CT imaging requires new ways of working. It is highly rewarding from a clinical perspective, but it also proves to be a daily challenge in terms of management. [less ▲]Detailed reference viewed: 19 (4 ULg)
18F-FDG Uptake Assessed by PET/CT in Abdominal Aortic Aneurysms Is Associated with Cellular and Molecular Alterations Prefacing Wall Deterioration and Rupture.
Courtois, Audrey ; Richelle, Betty ; Hustinx, Roland et al
in Journal of Nuclear Medicine (The) (2013), 54
Rupture of abdominal aortic aneurysms (AAAs) leads to a significant morbidity and mortality in aging populations, and its prediction would be most beneficial to public health. Spots of positive uptake of ... [more ▼]
Rupture of abdominal aortic aneurysms (AAAs) leads to a significant morbidity and mortality in aging populations, and its prediction would be most beneficial to public health. Spots of positive uptake of 18F-FDG detected by PET are found in 12% of AAA patients (PET+), who are most often symptomatic and at high rupture risk. Comparing the 18F-FDG-positive site with a negative site from the same aneurysm and with samples collected from AAA patients with no 18F-FDG uptake should allow the discrimination of biologic alterations that would help in identifying markers predictive of rupture. METHODS: Biopsies of the AAA wall were obtained from patients with no 18F-FDG uptake (PET0, n = 10) and from PET+ patients (n = 8), both at the site of positive uptake and at a distant negative site of the aneurysmal wall. Samples were analyzed by immunohistochemistry, quantitative real-time polymerase chain reaction, and zymography. RESULTS: The sites of the aneurysmal wall with a positive 18F-FDG uptake were characterized by a strikingly increased number of adventitial inflammatory cells, highly proliferative, and by a drastic reduction of smooth muscle cells (SMCs) in the media as compared with their negative counterpart and with the PET0 wall. The expression of a series of genes involved in the maintenance and remodeling of the wall was significantly modified in the negative sites of PET+, compared with the PET0 wall, suggesting a systemic alteration of the aneurysmal wall. Furthermore, a striking increase of several matrix metalloproteinases (MMPs), notably the MMP1 and MMP13 collagenases, was observed in the positive sites, mainly in the adventitia. Moreover, PET+ patients were characterized by a higher circulating C-reactive protein. CONCLUSION: Positive 18F-FDG uptake in the aneurysmal wall is associated with an active inflammatory process characterized by a dense infiltrate of proliferating leukocytes in the adventitia and an increased circulating C-reactive protein. Moreover, a loss of SMC in the media and alterations of the expression of genes involved in the remodeling of adventitia and collagen degradation potentially participate in the weakening of the aneurysmal wall preceding rupture. [less ▲]Detailed reference viewed: 87 (38 ULg)
The prognostic value of preoperative FDG PET-CT in hepatocellular carcinoma treated by liver transplantation.
; DETRY, Olivier ; BLETARD, Noëlla et al
in PROCEEDINGS OF THE XVIth SYMPOSIUM OF THE BELGIAN SOCIETY OF NUCLEAR MEDICINE (2013, May)Detailed reference viewed: 4 (0 ULg)
Brain dead yet mind alive: A positron emission tomography case study of brain metabolism in Cotard’s syndrome
Charland-Verville, Vanessa ; Bruno, Marie-Aurélie ; Bahri, Mohamed Ali et al
in Cortex : A Journal Devoted to the Study of the Nervous System & Behavior (2013), 49(7), 1997-1999Detailed reference viewed: 46 (10 ULg)
Automated platform for the quality control of PET-CT scanners following AFCN/FANC recommendations
Bernard, Claire ; ; JODOGNE, Sébastien et al
in Proceedings of the Belgian Hospital Physicists Association Symposium (2013, February)Detailed reference viewed: 28 (15 ULg)
Image of the month: Neurogenic myositis ossificans
; ; et al
in Revue Médicale de Liège (2013), 68(2), 53-5Detailed reference viewed: 5 (1 ULg)
(111)Indium-oxine labelling for evaluating the homing process of autologous osteoblasts implanted percutaneously in atrophic nonunion fractures.
; Bernard, Claire ; 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 ▲]Detailed reference viewed: 55 (30 ULg)
Prognostic value of FDG PET/CT in patients with hepatocellular carcinoma treated with liver transplantation.
; DETRY, Olivier ; BLETARD, Noëlla et al
in European Journal of Nuclear Medicine and Molecular Imaging (2013), 2013(SUPPL), 287Detailed reference viewed: 6 (2 ULg)
Imaging osteoarthritis using (18F)FPRGD2 PET/CT : observation and potential application.
WITHOFS, Nadia ; ALVAREZ MIEZENTSEVA, Victoria ; SIMONI, Paolo et al
in Journal of Nuclear Medicine (The) (2013), 54(SUPPL), 250Detailed reference viewed: 9 (3 ULg)
Prognostic value of FDG PET/CT in patients with lung tumors treated by Cyberknife.
LOVINFOSSE, Pierre ; JANVARY, Zsolt Levente ; JANSEN, Nicolas et al
in Journal of Nuclear Medicine (The) (2013), 54(SUPPL), 567Detailed reference viewed: 25 (5 ULg)
L'image du mois: La myosite ossifiante neurogene.
; ; et al
in Revue medicale de Liege (2013), 68(2), 53-5Detailed reference viewed: 18 (7 ULg)
FDG PET/CT in Crohn's disease: correlation of quantitative FDG PET/CT parameters with clinical and endoscopic surrogate markers of disease activity.
; ; et al
in European journal of nuclear medicine and molecular imaging (2013)
PURPOSE: The aim of this study was to determine the feasibility and potential clinical utility of assessment of Crohn's disease (CD) activity by 18F-fluorodeoxyglucose (FDG) positron emission tomography ... [more ▼]
PURPOSE: The aim of this study was to determine the feasibility and potential clinical utility of assessment of Crohn's disease (CD) activity by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT employing a new quantitative approach. METHODS: A total of 22 subjects (mean age 37) with CD who had undergone FDG PET/CT followed by ileocolonoscopy within 1 week were included in this analysis. The CD endoscopy index of severity (CDEIS) for various bowel segments was calculated. The CD activity index (CDAI) was evaluated, and fecal calprotectin was measured. On PET, regions with increased FDG uptake in large bowel were segmented with an adaptive contrast-oriented thresholding algorithm, and metabolically active volume (MAV), uncorrected mean standardized uptake value (SUVmean), partial volume-corrected SUVmean (PVC-SUVmean), SUVmax, uncorrected total lesion glycolysis (TLG = MAV x SUVmean), and PVC total lesion glycolysis (PVC-TLG = MAV x PVC-SUVmean) were measured. Global CD activity score (GCDAS) was calculated as the sum of PVC-TLG over all clinically significant FDG-avid regions in each subject. Correlations between regional PET quantification measures (SUVs, TLGs) and CDEIS were calculated. Correlations between the global PET quantification measure (GCDAS, global SUVs) with CDAI, fecal calprotectin, CDEIS, and CRP level were also calculated. RESULTS: SUVmax, PVC-SUVmean, and PVC-TLG significantly correlated with segment CDEIS subscores (r = 0.50, r = 0.69, and r = 0.31, respectively; p < 0.05). GCDAS significantly correlated with CDAI and fecal calprotectin (r = 0.64 and r = 0.51, respectively; p < 0.05). CONCLUSION: By employing this new quantitative approach, we were able to calculate indices of regional and global CD activity, which correlated well with both clinical and pathological disease activity surrogate markers. This approach may be of clinical importance in measuring both global disease activity and treatment response in patients with CD. [less ▲]Detailed reference viewed: 26 (3 ULg)
Multiclass classification of FDG PET scans for the distinction between Parkinson's disease and atypical parkinsonian syndromes
Garraux, Gaëtan ; Phillips, Christophe ; Schrouff, Jessica et al
in NeuroImage: Clinical (2013), 2
Most available pattern recognition methods in neuroimaging address binary classification problems. Here, we used relevance vector machine (RVM) in combination with booststrap resampling (‘bagging’) for ... [more ▼]
Most available pattern recognition methods in neuroimaging address binary classification problems. Here, we used relevance vector machine (RVM) in combination with booststrap resampling (‘bagging’) for non-hierarchical multiclass classification. The method was tested on 120 cerebral 18fluorodeoxyglucose (FDG) positron emission tomography (PET) scans performed in patients who exhibited parkinsonian clinical features for 3.5 years on average but that were outside the prevailing perception for Parkinson's disease (PD). A radiological diagnosis of PD was suggested for 30 patients at the time of PET imaging. However, at follow-up several years after PET imaging, 42 of them finally received a clinical diagnosis of PD. The remaining 78 APS patients were diagnosed with multiple system atrophy (MSA, N = 31), progressive supranuclear palsy (PSP, N = 26) and corticobasal syndrome (CBS, N = 21), respectively. With respect to this standard of truth, classification sensitivity, specificity, positive and negative predictive values for PD were 93% 83% 75% and 96%, respectively using binary RVM (PD vs. APS) and 90%, 87%, 79% and 94%, respectively, using multiclass RVM (PD vs. MSA vs. PSP vs. CBS). Multiclass RVM achieved 45%, 55% and 62% classification accuracy for, MSA, PSP and CBS, respectively. Finally, a majority confidence ratio was computed for each scan on the basis of class pairs that were the most frequently assigned by RVM. Altogether, the results suggest that automatic multiclass RVM classification of FDG PET scans achieves adequate performance for the early differentiation between PD and APS on the basis of cerebral FDG uptake patterns when the clinical diagnosis is felt uncertain. This approach cannot be recommended yet as an aid for distinction between the three APS classes under consideration. [less ▲]Detailed reference viewed: 50 (13 ULg)
Newer Methods for Improving Yield from FDG-PET Imaging for Accurate Staging, Determining Tumor Biology, and Assessing Prognosis
in PET Clinics (2012), 7(4), 425-430Detailed reference viewed: 5 (1 ULg)
Cluster headache Award 2012: Central modulation in cluster headache patients treated with occipital nerve stimulation
MAGIS, Delphine ; Bruno, Marie-Aurélie ; FUMAL, Arnaud et al
in Journal of Headache & Pain (2012, September 16)Detailed reference viewed: 30 (6 ULg)
Primary hyperparathyroidism confirmed by histology : sensitivity and predictors of 99mTc-Sestamibi/CT scan
VALDES SOCIN, Hernan Gonzalo ; BISOGNI, Carmen ; BETEA, Daniela et al
in Abstract Book - 13th International Workshop on Multiple Endocrine Neoplasia (2012, September)Detailed reference viewed: 30 (7 ULg)
Preliminary results of (18F)FPRGD2 PET/CT imaging of integrin αvβ3 levels in patients with locally advanced rectal carcinoma.
WITHOFS, Nadia ; MARTINIVE, Philippe ; SCAGNOL, Irène et al
in Journal of Nuclear Medicine (The) (2012), 53(SUPPL), 1703Detailed reference viewed: 45 (25 ULg)