FDG-positron emission tomography (PET) has high diagnostic accuracy in cardiac sarcoidosis (CS). Beyond CS, the non invasive diagnosis of inflammatory cardiomyopathies (IC) is challenged by a lower diagnostic performance of usual tools as magnetic resonance imaging (MRI). 17 consecutive patients with suspected IC had a FDG-PET to detect myocardial inflammation. From all clinical data including PET, we classified patients in either CS or non-CS and respective PET data were compared. The clinical impact of adding PET in the non-CS group was evaluated by comparing diagnosis and management proposed by an expert blind to PET with final diagnosis and management actually held in practice. 6 patients had CS, all with positive PET. In the 11 non-CS patients, 7 had a positive PET. All had MRI late gadolinium enhancement in FDG uptake areas, suggesting a true positivity of PET for the presence of inflammation. PET data were all significantly different between CS and nonCS patients with positive PET, particularly the coefficient of variation of cardiac SUV which is an index of heterogeneity of FDG uptake was significantly greater in CS patients (0,4 vs 0,17 p<0,002). In non-CS patients, 2 were classified as certain IC, 2 as excluded IC, and 7 as possible IC by an expert blind to PET. Adding PET in clinical practice, IC was excluded for 5 of the 7 patients with possible IC, 2 patients remained with a possible IC diagnosis and the 2 certain IC were confirmed. PET did not change patient management in terms of endomyocardial biopsy or immunosuppressive therapy. Some patients with suspected IC had a positive FDG-PET in favour of myocardial inflammation, with a different pattern from that observed in CS. Adding PET to usual diagnostic tools led to a decrease of possible IC diagnosis that turned in excluded IC. These preliminary data suggest a potential role of PET for the non-invasive diagnosis of IC that will need further investigations.Download : Download high-res image (89KB)Download : Download full-size imageAbstract 0049 – Figure: FDG uptake concordant with MRI-LGE Abstract 0049 – Figure: FDG uptake concordant with MRI-LGE

La TEP au 68Ga-DOTANOC est un traceur performant dans l’exploration des tumeurs neuro-endocrines (TNE) qui surexpriment les récepteurs de la somatostatine. L’intensité de fixation est un indicateur de bonne différenciation neuro-endocrine et d’un pronostic plus favorable. L’objectif de notre travail était d’évaluer l’impact de la durée d’acquisition et du délai entre l’injection et la réalisation de l’imagerie sur les paramètres quantitatifs. Quinze patients porteurs de TNE digestives ont bénéficié d’une TEP 60 min après injection (p.i.) de 148 ± 20 MBq de 68Ga-DOTANOC avec un pas de 5 min par position de lit, suivie par une acquisition en mode-list de 8 min, 120 min p.i. Cent neuf lésions au total ont été analysées et classées en fonction de leur taille et de leur site. La variation de différents paramètres quantitatifs (SUVmax, SUVmoyenne, SUVpeak, volume tumoral et contrast-to-noise ratio (CNR) dans le foie), a été étudiée en fonction de la durée d’acquisition et du délai p.i. en utilisant les tests statistiques de Mann-Whitney et Friedman (significativité : p < 0,05). Il n’a pas été mis en évidence d’impact significatif du délai d’acquisition p.i. sur tous les paramètres testés quelle que soit la taille ou localisation lésionnelle. Une durée d’acquisition de 3 min modifiait statistiquement les résultats (sauf quand comparé à l’acquisition de 4 min), mais les différences observées n’avaient pas de conséquence sur l’interprétation compte tenu de l’intensité de fixation élevée des lésions (médiane des SUVmax de 21,8 ; extrêmes : 3 à 283). Le CNR de l’acquisition de 3 min était systématiquement inférieur aux CNR obtenus avec des acquisitions > 5 min suggérant une meilleure détectabilité des lésions hépatiques pour une durée d’acquisition plus longue mais, là encore, sans conséquence significative sur l’interprétation. Ces résultats préliminaires suggèrent qu’il n’y a pas de différence quantitative et qualitative significative entre les acquisitions réalisées à 60 min et à 120 min p.i. et qu’une durée d’acquisition de 3 min par pas est probablement cliniquement suffisante. Des résultats complémentaires évaluant un temps d’acquisition plus court seront présentés lors du congrès.

Aim. - Analyse early dynamic F-18-Choline (FCH) PET/CT acquisitions to define lymph nodes and prostate pathological status.Patients and methods. - Retrospective analysis was performed on 39 patients for initial staging (n = 18) or after initial treatment (n = 21). Patients underwent 10 minutes dynamic acquisitions centered on pelvis, after injection of 3-4 MBq/kg of FCH. Whole body images were performed about 1 hour after injection and were acquired on PET/CT GE Discovery LS (GE-LS) or Siemens Biograph mCT (mCT). Maximum SUVaccording to time was measured on lymph nodes and prostate lesions. The status of each lesion was based on histological results or patient follow-up (> 6 months).Results. - The median PSA was 8.46 ng/mL and the median Gleason 3+4. Ninety-two lesions (43 lymph nodes and 49 prostate lesions) were analyzed, including 63 malignant lesions. In early dynamic acquisitions, the maximum SUV was significantly higher, respectively on mCT and GE-LS, in positive lymph nodes (P < 0.001, P = 0.007) and prostate (P = 0.001, P = 0.02). ROC curves showed for lymph nodes acquired on mCT, a trend to better numbers of sensitivity and specificity for early acquisitions, compared with late acquisitions.Conclusion. - Assessment of lymph nodes and prostate pathological status with early dynamic curves PET/CT FCH was interestingly possible in a disease where proofs of malignancy are difficult to obtain. (C) 2015 Elsevier Masson SAS. All rights reserved.

The heat transfer through the floor slab in buildings with Under-Floor Air Distribution (UFAD) systems may have a negative impact on the energy performance of these buildings, although very few studies have been reported in the literature. By using an energy simulation program, EnergyPlus, this investigation compared the energy use in a Philadelphia office building with a UFAD system to that with a well-mixed ventilation system. When the heat transfer through the floor slab was taken into consideration, the thermal load of the building with the UFAD system was higher than with the well-mixed system. On the other hand, the higher supply air temperature of the UFAD system enables the use of more free-cooling. The annual energy consumption by the chillers in the building with the UFAD system was 16–27% lower than with the well-mixed system, but energy consumption by the boiler was 12–30% higher, and the energy consumption by the fan was 22–50% higher, depending on the manner in which the heat was supplied to the floor plenum. When the UFAD system was used with an un-ducted floor plenum and without heating coils under the diffusers, it consumed slightly more energy than the well-mixed system.