22 results on '"Jaudet, Cyril"'
Search Results
2. Upfront F18-choline PET/CT versus Tc99m-sestaMIBI SPECT/CT guided surgery in primary hyperparathyroidism: the randomized phase III diagnostic trial APACH2
- Author
-
Quak, Elske, Lasne Cardon, Audrey, Ciappuccini, Renaud, Lasnon, Charline, Bastit, Vianney, Le Henaff, Véronique, Lireux, Barbara, Foucras, Gauthier, Jaudet, Cyril, Berchi, Celia, Grellard, Jean-Michel, Lequesne, Justine, Clarisse, Bénédicte, and Bardet, Stéphane
- Published
- 2021
- Full Text
- View/download PDF
3. Quantum oscillations in underdoped YBa_2Cu_3O_6.5
- Author
-
Jaudet, Cyril, Levallois, Julien, Audouard, Alain, Vignolles, David, Vignolle, Baptiste, Liang, Ruixing, Bonn, D. A., Hardy, W. N., Hussey, N. E., Taillefer, Louis, and Proust, Cyril
- Subjects
Condensed Matter - Superconductivity ,Condensed Matter - Strongly Correlated Electrons - Abstract
Shubnikov-de Haas and de Haas-van Alphen effects have been measured in the underdoped high temperature superconductor YBa$_2$Cu$_3$O$_{6.51}$. Data are in agreement with the standard Lifshitz-Kosevitch theory, which confirms the presence of a coherent Fermi surface in the ground state of underdoped cuprates. A low frequency $F = 530 \pm 10$ T is reported in both measurements, pointing to small Fermi pocket, which corresponds to 2% of the first Brillouin zone area only. This low value is in sharp contrast with that of overdoped Tl$_2$Ba$_2$CuO$_{6+\delta}$, where a high frequency $F = 18$ kT has been recently reported and corresponds to a large hole cylinder in agreement with band structure calculations. These results point to a radical change in the topology of the Fermi surface on opposing sides of the cuprate phase diagram., Comment: proceeding of the ECRYS-2008
- Published
- 2010
- Full Text
- View/download PDF
4. Multiple Quantum Oscillations in the de Haas van Alphen Spectra of the Underdoped High Temperature Superconductor YBa_2Cu_3O_6.5
- Author
-
Audouard, Alain, Jaudet, Cyril, Vignolles, David, Liang, Ruixing, Bonn, D. A., Hardy, W. N., Taillefer, Louis, and Proust, Cyril
- Subjects
Condensed Matter - Superconductivity ,Condensed Matter - Strongly Correlated Electrons - Abstract
By improving the experimental conditions and extensive data accumulation, we have achieved very high-precision in the measurements of the de Haas-van Alphen effect in the underdoped high-temperature superconductor YBa$_{2}$Cu$_{3}$O$_{6.5}$. We find that the main oscillation, so far believed to be single-frequency, is composed of three closely spaced frequencies. We attribute this to bilayer splitting and warping of a single quasi-2D Fermi surface, indicating that \emph{c}-axis coherence is restored at low temperature in underdoped cuprates. Our results do not support the existence of a larger frequency of the order of 1650 T reported recently in the same compound [S.E. Sebastian {\it et al}., Nature {\bf 454}, 200 (2008)].
- Published
- 2008
- Full Text
- View/download PDF
5. Bond-order modulated staggered flux phase for the $t{-}J$ model on the square lattice
- Author
-
Weber, Cedric, Poilblanc, Didier, Capponi, Sylvain, Mila, Frederic, and Jaudet, Cyril
- Subjects
Condensed Matter - Strongly Correlated Electrons ,Condensed Matter - Superconductivity - Abstract
Motivated by the observation of inhomogeneous patterns in some high-T$_c$ cuprate compounds, several variational Gutzwiller-projected wave-functions with built-in charge and bond order parameters are proposed for the extended $t-J-V$ model on the square lattice at low doping. First, following a recent Gutzwiller-projected mean-field approach by one of us (Phys. Rev. B. {\bf 72}, 060508(R) (2005)), we investigate, as a function of doping and Coulomb repulsion, the stability of the staggered flux phase with respect to small spontaneous modulations of squared unit cells ranging from $2\times 2$ to $\sqrt{32}\times\sqrt{32}$. It is found that a $4\times 4$ bond-order (BO) modulation appears spontaneously on top of the staggered flux pattern for hole doping around 1/8. A related wave-function is then constructed and optimized accurately and its properties studied extensively using an approximation-free variational Monte Carlo scheme. Finally, the competition of the BO-modulated staggered flux wave-function w.r.t. the d-wave RVB wave-function or the commensurate flux state is investigated. It is found that a short range Coulomb repulsion penalizes the d-wave superconductor and that a moderate Coulomb repulsion brings them very close in energy. Our results are discussed in connection to the STM observations in the under-doped regime of some cuprates., Comment: 10 pages, 9 figures
- Published
- 2006
- Full Text
- View/download PDF
6. Deep Learning Denoising Improves and Homogenizes Patient [18F]FDG PET Image Quality in Digital PET/CT
- Author
-
Weyts, Kathleen, primary, Quak, Elske, additional, Licaj, Idlir, additional, Ciappuccini, Renaud, additional, Lasnon, Charline, additional, Corroyer-Dulmont, Aurélien, additional, Foucras, Gauthier, additional, Bardet, Stéphane, additional, and Jaudet, Cyril, additional
- Published
- 2023
- Full Text
- View/download PDF
7. Artificial intelligence-based 68Ga-DOTATOC PET denoising for optimizing 68Ge/68Ga generator use throughout its lifetime
- Author
-
Quak, Elske, primary, Weyts, Kathleen, additional, Jaudet, Cyril, additional, Prigent, Anaïs, additional, Foucras, Gauthier, additional, and Lasnon, Charline, additional
- Published
- 2023
- Full Text
- View/download PDF
8. Deep Hybrid Learning Prediction of Patient-Specific Quality Assurance in Radiotherapy: Implementation in Clinical Routine
- Author
-
Moreau, Noémie, primary, Bonnor, Laurine, additional, Jaudet, Cyril, additional, Lechippey, Laetitia, additional, Falzone, Nadia, additional, Batalla, Alain, additional, Bertaut, Cindy, additional, and Corroyer-Dulmont, Aurélien, additional
- Published
- 2023
- Full Text
- View/download PDF
9. Deep Learning Denoising Improves and Homogenizes Patient [ 18 F]FDG PET Image Quality in Digital PET/CT.
- Author
-
Weyts, Kathleen, Quak, Elske, Licaj, Idlir, Ciappuccini, Renaud, Lasnon, Charline, Corroyer-Dulmont, Aurélien, Foucras, Gauthier, Bardet, Stéphane, and Jaudet, Cyril
- Subjects
POSITRON emission tomography ,DEEP learning ,CONVOLUTIONAL neural networks ,SIGNAL convolution ,RADIATION protection - Abstract
Given the constant pressure to increase patient throughput while respecting radiation protection, global body PET image quality (IQ) is not satisfactory in all patients. We first studied the association between IQ and other variables, in particular body habitus, on a digital PET/CT. Second, to improve and homogenize IQ, we evaluated a deep learning PET denoising solution (Subtle PET
TM ) using convolutional neural networks. We analysed retrospectively in 113 patients visual IQ (by a 5-point Likert score in two readers) and semi-quantitative IQ (by the coefficient of variation in the liver, CVliv ) as well as lesion detection and quantification in native and denoised PET. In native PET, visual and semi-quantitative IQ were lower in patients with larger body habitus (p < 0.0001 for both) and in men vs. women (p ≤ 0.03 for CVliv ). After PET denoising, visual IQ scores increased and became more homogeneous between patients (4.8 ± 0.3 in denoised vs. 3.6 ± 0.6 in native PET; p < 0.0001). CVliv were lower in denoised PET than in native PET, 6.9 ± 0.9% vs. 12.2 ± 1.6%; p < 0.0001. The slope calculated by linear regression of CVliv according to weight was significantly lower in denoised than in native PET (p = 0.0002), demonstrating more uniform CVliv . Lesion concordance rate between both PET series was 369/371 (99.5%), with two lesions exclusively detected in native PET. SUVmax and SUVpeak of up to the five most intense native PET lesions per patient were lower in denoised PET (p < 0.001), with an average relative bias of −7.7% and −2.8%, respectively. DL-based PET denoising by Subtle PETTM allowed [18 F]FDG PET global image quality to be improved and homogenized, while maintaining satisfactory lesion detection and quantification. DL-based denoising may render body habitus adaptive PET protocols unnecessary, and pave the way for the improvement and homogenization of PET modalities. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
10. The Impact of Resampling and Denoising Deep Learning Algorithms on Radiomics in Brain Metastases MRI
- Author
-
Moummad, Ilyass, primary, Jaudet, Cyril, additional, Lechervy, Alexis, additional, Valable, Samuel, additional, Raboutet, Charlotte, additional, Soilihi, Zamila, additional, Thariat, Juliette, additional, Falzone, Nadia, additional, Lacroix, Joëlle, additional, Batalla, Alain, additional, and Corroyer-Dulmont, Aurélien, additional
- Published
- 2021
- Full Text
- View/download PDF
11. Radioimmunotherapy for Brain Metastases: The Potential for Inflammation as a Target of Choice
- Author
-
Corroyer-Dulmont, Aurélien, primary, Jaudet, Cyril, additional, Frelin, Anne-Marie, additional, Fantin, Jade, additional, Weyts, Kathleen, additional, Vallis, Katherine A., additional, Falzone, Nadia, additional, Sibson, Nicola R., additional, Chérel, Michel, additional, Kraeber-Bodéré, Françoise, additional, Batalla, Alain, additional, Bardet, Stéphane, additional, Bernaudin, Myriam, additional, and Valable, Samuel, additional
- Published
- 2021
- Full Text
- View/download PDF
12. The Impact of Artificial Intelligence CNN Based Denoising on FDG PET Radiomics
- Author
-
Jaudet, Cyril, primary, Weyts, Kathleen, additional, Lechervy, Alexis, additional, Batalla, Alain, additional, Bardet, Stéphane, additional, and Corroyer-Dulmont, Aurélien, additional
- Published
- 2021
- Full Text
- View/download PDF
13. Gated 18F-FDG PET/CT of the Lung Using a Respiratory Spirometric Gating Device: A Feasibility Study
- Author
-
Jaudet, Cyril, primary, Filleron, Thomas, additional, Weyts, Kathleen, additional, Didierlaurent, David, additional, Vallot, Delphine, additional, Ouali, Mounia, additional, Zerdoud, Slimane, additional, Dierickx, O. Lawrence, additional, Caselles, Olivier, additional, and Courbon, Frédéric, additional
- Published
- 2019
- Full Text
- View/download PDF
14. Limits of radiomic-based entropy as a surrogate of tumor heterogeneity: ROI-area, acquisition protocol and tissue site exert substantial influence
- Author
-
Dercle, Laurent, Ammari, Samy, Bateson, Mathilde, Durand, Paul Blanc, Haspinger, Eva, Massard, Christophe, Jaudet, Cyril, Varga, Andrea, Deutsch, Eric, Soria, Jean-Charles, Ferte, Charles, and Radiation Therapy
- Abstract
Entropy is a promising quantitative imaging biomarker for characterizing cancer imaging phenotype. Entropy has been associated with tumor gene expression, tumor metabolism, tumor stage, patient prognosis, and treatment response. Our hypothesis states that tumor-specific biomarkers such as entropy should be correlated between synchronous metastases. Therefore, a significant proportion of the variance of entropy should be attributed to the malignant process. We analyzed 112 patients with matched/paired synchronous metastases (SM#1 and SM#2) prospectively enrolled in the MOSCATO-01 clinical trial. Imaging features were extracted from Regions Of Interest (ROI) delineated on CT-scan using TexRAD software. We showed that synchronous metastasis entropy was correlated across 5 Spatial Scale Filters: Spearman's Rho ranged between 0.41 and 0.59 (P = 0.0001, Bonferroni correction). Multivariate linear analysis revealed that entropy in SM#1 is significantly associated with (i) primary tumor type; (ii) entropy in SM#2 (same malignant process); (iii) ROI area size; (iv) metastasis site; and (v) entropy in the psoas muscle (reference tissue). Entropy was a logarithmic function of ROI area in normal control tissues (aorta, psoas) and in mathematical models (P
- Published
- 2017
15. Limits of radiomic-based entropy as a surrogate of tumor heterogeneity: ROI-area, acquisition protocol and tissue site exert substantial influence
- Author
-
Dercle, Laurent, primary, Ammari, Samy, additional, Bateson, Mathilde, additional, Durand, Paul Blanc, additional, Haspinger, Eva, additional, Massard, Christophe, additional, Jaudet, Cyril, additional, Varga, Andrea, additional, Deutsch, Eric, additional, Soria, Jean-Charles, additional, and Ferté, Charles, additional
- Published
- 2017
- Full Text
- View/download PDF
16. Gated 18F-FDG PET/CT of the Lung Using a Respiratory Spirometric Gating Device: A Feasibility Study.
- Author
-
Jaudet, Cyril, Filleron, Thomas, Weyts, Kathleen, Didierlaurent, David, Vallot, Delphine, Ouali, Mounia, Zerdoud, Slimane, Dierickx, O. Lawrence, Caselles, Olivier, and Courbon, Frédéric
- Subjects
LUNG physiology ,DIAGNOSTIC imaging equipment ,PILOT projects ,DIGITAL image processing ,LUNGS ,RADIOPHARMACEUTICALS ,DEOXY sugars - Abstract
Spirometric gating devices (SGDs) can measure the respiratory signal with high temporal resolution and accuracy. The primary objective of this study was to assess the feasibility and tolerance of a gated lung PET/CT acquisition using an SGD. The secondary objective was to compare the technical quality, accuracy, and interoperability of the SGD with that of a standard respiratory gating device, Real-Time Position Management (RPM), based on measurement of vertical thoracoabdominal displacement. Methods: A prospective phase I monocentric clinical study was performed on patients undergoing 18F-FDG PET/CT for assessment of a solitary lung nodule, staging of lung malignancy, or planning of radiotherapy. After whole-body PET/CT, a centered gated acquisition of both PET and CT was simultaneously obtained with the SGD and RPM during normal breathing. Results: Of the 46 patients who were included, 6 were prematurely excluded (1 because of hyperglycemia and 5 because of distant metastases revealed by whole-body PET/CT, leading to an unjustified extra gated acquisition). No serious adverse events were observed. Of the 40 remaining patients, the gated acquisition was prematurely stopped in 1 patient because of mask discomfort (2.5%; confidence interval [CI], 0.1%-13.2%). This event was considered patient tolerance failure. The SGD generated accurately gated PET/CT images, with more than 95% of the breathing cycle detected and high temporal resolution, in 34 of the 39 patients (87.2%; 95% CI, 60.0%-100.0%) and failed to generate a biologic tumor volume in 1 of 21 patients with increased 18F-FDG uptake (4.8%; 95% CI, 0.1%-26.5%). The quality and accuracy of respiratory signal detection and synchronization were significantly better than those obtained with RPM (P < 0.05). Conclusion: This trial supports the use of an SGD for gated lung PET/CT because of its high patient tolerance and accuracy. Although this technique seems to technically outperform RPM for gated PET/CT, further assessment of its superiority and the clinical benefit is warranted. We believe that this technique could be used as a gold standard to develop innovative approaches to eliminate respiration-induced blurring artifacts. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
17. Dynamic Scintigraphy With SPECT-CT of Postoperative Salivary Leak
- Author
-
Weyts, Kathleen, Spinato, Linda, Bisschop, Pierre, Jaudet, Cyril, Hambye, Anne Sophie, Weyts, Kathleen, Spinato, Linda, Bisschop, Pierre, Jaudet, Cyril, and Hambye, Anne Sophie
- Abstract
This 65 year-old woman, 1 month postoperative after maxillary sinus carcinoma (pT4N0cM0) excision and reconstruction, presented with significant left facial clear fluid wound leakage. A salivary or cerebrospinal leakage was suspected. Fluid analysis, CT, and MRI were noncontributory. Dynamic salivary scintigraphy with SPECT-CT allowed for the detection and localization of the leakage from the left parotid gland. Radioactive dose rate of the wound bandage was 50 μSv/h compared with 0.05 μSv/h for background and confirmed the diagnosis. Left total parotidectomy resulted in resolution., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2016
18. Effet de Haas-van Alphen dans les supraconducteurs à haute température critique
- Author
-
Jaudet, Cyril and Jaudet, Cyril
- Abstract
Ce travail de thèse est basé sur des mesures d'oscillations quantiques de l'aimantation dans les supraconducteurs à haute température critique. Ces matériaux ont été découvert en 986 par Bednorz et Müller. Ils sont caractérisés par la présence de plans CuO2 dont on peut faire varier la concentration électronique. A faible dopage, ces systèmes se comportent comme un isolant, les électrons étant localisés par une forte répulsion coulombienne. A très fort dopage, ces systèmes retrouvent un comportement de type liquide de Fermi. Entre ces deux extrêmes, un dôme supraconducteur, dont la température critique maximum correspond au dopage dit optimum, apparaît. Différentes sondes expérimentales ont révélé, du côté sous-dopé, la présence d'une phase dite \emph{pseudogap}. La physique de ces systèmes soulève plusieurs questions fondamentales: quelle est la nature de cette phase \emph{pseudogap}, quel est le mécanisme d'appariement à l'origine de la supraconductivité. Au cours de cette thèse, nous avons développé un système de mesure de l'aimantation par cantilever piezorésistif sous champ magnétique intense à très basse température. Nos mesures ont révélé la présence d'oscillations quantiques de l'aimantation des deux cotés du diagramme de phase et ce pour la première fois. Ces oscillations prouvent l'existence d'une surface de Fermi fermée et cohérente qui évolue d'une large orbite de trou du côté sur-dopé à une surface de Fermi contenant une ou plusieurs petites poches du côté sous-dopé. De plus, la présence d'un battement de ces oscillations suggère la restauration de la cohérence selon l'axe c à très basse température du côté sous-dopé du diagramme de phase. Ces différents faits expérimentaux vont dans le sens d'un état fondamental de type liquide de Fermi. Le \emph{pseudogap} marquerait alors l'apparition d'une phase ordonnée en compétition avec la supraconductivité., This thesis work is based on quantum oscillation measurements of the magnetization in high temperature superconductors. These materials were discovered in 1986 by Bednorz and Müller. They are characterized by the presence of CuO2 planes of which the electronic concentration can be changed. At low doping, these systems have insulating behavior, the electron being localised by strong Coulomb repulsion. At very high doping, these systems recover Fermi liquid behavior. Between these two extremes there is a superconducting dome at which the maximum critical temperature corresponding to a doping, called optimum, arises. Various experimental probes reveal, on the underdoped side, the presence of the so-called \emph{pseudogap} phase. The physics of this system raise several fundamental questions: What is the nature of this \emph{pseudogap} phase and what is the pairing mechanism at the origin of this superconductivity. During this thesis, we have developed a measurent system of the magnetization with a piezoresistive cantilever under high magnetic field and at very low temperature. Our measurements have revealed the presence of quantum oscillations of the magnetization for the first time on each side of the phase diagram. These oscillations attest of the existence of a closed and coherent Fermi surface which evolves from a huge orbit of holes on the overdoped side to a Fermi surface containing one or several small pockets on the underdoped side. Moreover, the presence of a beating in these oscillations suggest the restoration of the coherence along the c-axis at very low temperature and at very high magnetic field on the underdoped side. These different experimental facts are consistent with a Fermi liquid fundamental state. The \emph{pseudogap} is a hallmark of the appearance of an ordered phase in competition with superconductivity.
- Published
- 2009
19. The Impact of Resampling and Denoising Deep Learning Algorithms on Radiomics in Brain Metastases MRI.
- Author
-
Moummad, Ilyass, Jaudet, Cyril, Lechervy, Alexis, Valable, Samuel, Raboutet, Charlotte, Soilihi, Zamila, Thariat, Juliette, Falzone, Nadia, Lacroix, Joëlle, Batalla, Alain, and Corroyer-Dulmont, Aurélien
- Subjects
- *
BRAIN , *DEEP learning , *METASTASIS , *MAGNETIC resonance imaging , *RETROSPECTIVE studies , *BRAIN tumors , *T-test (Statistics) , *DESCRIPTIVE statistics , *DATA analysis software , *STATISTICAL models , *ALGORITHMS - Abstract
Simple Summary: Due to the central role of magnetic resonance Imaging (MRI) in the management of patients with cancer, waiting lists exceed clinically relevant delays. For this reason, many research groups and MRI manufacturers develop algorithms as resampling and denoising models to allow faster acquisition time without deterioration in image quality. Whereas these algorithms are available in all new MRI, it is not clear how they will impact image features as well as the validity of statistical model of radiomics which use deep images characteristics to predict treatment outcome. The aim of this study was to develop resampling and denoising deep learning (DL) models and evaluate their impact on radiomics from post-Gd-T1w-MRI brain images with brain metastases. We show that resampling and denoising DL models reconstruct low resolution and noised MRI images acquired quickly into high quality images. While fast acquisition loses most of the radiomic-features and invalidates predictive radiomic models, DL models restore these parameters. Background: Magnetic resonance imaging (MRI) is predominant in the therapeutic management of cancer patients, unfortunately, patients have to wait a long time to get an appointment for examination. Therefore, new MRI devices include deep-learning (DL) solutions to save acquisition time. However, the impact of these algorithms on intensity and texture parameters has been poorly studied. The aim of this study was to evaluate the impact of resampling and denoising DL models on radiomics. Methods: Resampling and denoising DL model was developed on 14,243 T1 brain images from 1.5T-MRI. Radiomics were extracted from 40 brain metastases from 11 patients (2049 images). A total of 104 texture features of DL images were compared to original images with paired t-test, Pearson correlation and concordance-correlation-coefficient (CCC). Results: When two times shorter image acquisition shows strong disparities with the originals concerning the radiomics, with significant differences and loss of correlation of 79.81% and 48.08%, respectively. Interestingly, DL models restore textures with 46.15% of unstable parameters and 25.96% of low CCC and without difference for the first-order intensity parameters. Conclusions: Resampling and denoising DL models reconstruct low resolution and noised MRI images acquired quickly into high quality images. While fast MRI acquisition loses most of the radiomic features, DL models restore these parameters. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. Bond-order-modulated staggered-flux phase of thetJmodel on a square lattice
- Author
-
Weber, Cédric, Poilblanc, Didier, Capponi, Sylvain, Mila, Frédéric, and Jaudet, Cyril
- Subjects
Condensed Matter::Superconductivity ,Condensed Matter::Strongly Correlated Electrons - Abstract
Motivated by the observation of inhomogeneous patterns in some high-Tc cuprate compounds, several variational Gutzwiller-projected wave functions with built-in charge and bond-order parameters are proposed for the extended t−J−V model on the square lattice at low doping. First, following a recent Gutzwiller-projected mean-field approach by one of us [D. Poilblanc, Phys. Rev. B 72, 060508(R) (2005)], we investigate, as a function of doping and Coulomb repulsion the relative stability of a wide variety of modulated structures with square unit cells of size 2×2, √8×√8, 4×4, and √32×√32. It is found that the 4×4 bond-order wave function with staggered-flux pattern (and small charge and spin current density wave) is a remarkable competitive candidate for hole doping around 1∕8 in agreement with scanning tunneling microscopy observations in the underdoped regime of some cuprates. This wave function is then optimized accurately and its properties studied extensively using a variational Monte Carlo scheme. Moreover, we find that under increasing the Coulomb repulsion, the d-wave superconducting RVB wave function is rapidly destabilized with respect to the 4×4 bond-order wave function. The stability of the bond-modulated wave function is connected to a gain of Coulomb and exchange energies. We suggest that such ordering patterns could be dynamical or could spontaneously appear in the vicinity of an impurity or a vortex in the mixed phase of the cuprates. Finally, we consider also a commensurate flux phase, but this wave function turns out not to be competitive because of its rather poor kinetic energy. However, we find it has very competitive exchange and Coulomb energies.
21. Artificial intelligence-based 68 Ga-DOTATOC PET denoising for optimizing 68 Ge/ 68 Ga generator use throughout its lifetime.
- Author
-
Quak E, Weyts K, Jaudet C, Prigent A, Foucras G, and Lasnon C
- Abstract
Introduction: The yield per elution of a
68 Ge/68 Ga generator decreases during its lifespan. This affects the number of patients injected per elution or the injected dose per patient, thereby negatively affecting the cost of examinations and the quality of PET images due to increased image noise. We aimed to investigate whether AI-based PET denoising can offset this decrease in image quality parameters., Methods: All patients addressed to our PET unit for a68 Ga-DOTATOC PET/CT from April 2020 to February 2021 were enrolled. Forty-four patients underwent their PET scans according to Protocol_FixedDose (150 MBq) and 32 according to Protocol_WeightDose (1.5 MBq/kg). Protocol_WeightDose examinations were processed using the Subtle PET software (Protocol_WeightDoseAI ). Liver and vascular SUV mean were recorded as well as SUVmax, SUVmean and metabolic tumour volume (MTV) of the most intense tumoural lesion and its background SUVmean. Liver and vascular coefficients of variation (CV), tumour-to-background and tumour-to-liver ratios were calculated., Results: The mean injected dose of 2.1 (0.4) MBq/kg per patient was significantly higher in the Protocol_FixedDose group as compared to 1.5 (0.1) MBq/kg for the Protocol_WeightDose group. Protocol_WeightDose led to noisier images than Protocol_FixedDose with higher CVs for liver (15.57% ± 4.32 vs. 13.04% ± 3.51, p = 0.018) and blood-pool (28.67% ± 8.65 vs. 22.25% ± 10.37, p = 0.0003). Protocol_WeightDoseAI led to less noisy images than Protocol_WeightDose with lower liver CVs (11.42% ± 3.05 vs. 15.57% ± 4.32, p < 0.0001) and vascular CVs (16.62% ± 6.40 vs. 28.67% ± 8.65, p < 0.0001). Tumour-to-background and tumour-to-liver ratios were lower for protocol_WeightDoseAI : 6.78 ± 3.49 vs. 7.57 ± 4.73 ( p = 0.01) and 5.96 ± 5.43 vs. 6.77 ± 6.19 ( p < 0.0001), respectively. MTVs were higher after denoising whereas tumour SUVmax were lower: the mean% differences in MTV and SUVmax were + 11.14% (95% CI = 4.84-17.43) and -3.92% (95% CI = -6.25 to -1.59)., Conclusion: The degradation of PET image quality due to a reduction in injected dose at the end of the68 Ge/68 Ga generator lifespan can be effectively counterbalanced by using AI-based PET denoising., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Quak, Weyts, Jaudet, Prigent, Foucras and Lasnon.)- Published
- 2023
- Full Text
- View/download PDF
22. Gated 18 F-FDG PET/CT of the Lung Using a Respiratory Spirometric Gating Device: A Feasibility Study.
- Author
-
Jaudet C, Filleron T, Weyts K, Didierlaurent D, Vallot D, Ouali M, Zerdoud S, Dierickx OL, Caselles O, and Courbon F
- Subjects
- Adult, Aged, Aged, 80 and over, Feasibility Studies, Female, Humans, Image Processing, Computer-Assisted, Male, Middle Aged, Fluorodeoxyglucose F18, Lung diagnostic imaging, Lung physiology, Positron Emission Tomography Computed Tomography instrumentation, Respiratory-Gated Imaging Techniques instrumentation
- Abstract
Spirometric gating devices (SGDs) can measure the respiratory signal with high temporal resolution and accuracy. The primary objective of this study was to assess the feasibility and tolerance of a gated lung PET/CT acquisition using an SGD. The secondary objective was to compare the technical quality, accuracy, and interoperability of the SGD with that of a standard respiratory gating device, Real-Time Position Management (RPM), based on measurement of vertical thoracoabdominal displacement. Methods: A prospective phase I monocentric clinical study was performed on patients undergoing
18 F-FDG PET/CT for assessment of a solitary lung nodule, staging of lung malignancy, or planning of radiotherapy. After whole-body PET/CT, a centered gated acquisition of both PET and CT was simultaneously obtained with the SGD and RPM during normal breathing. Results: Of the 46 patients who were included, 6 were prematurely excluded (1 because of hyperglycemia and 5 because of distant metastases revealed by whole-body PET/CT, leading to an unjustified extra gated acquisition). No serious adverse events were observed. Of the 40 remaining patients, the gated acquisition was prematurely stopped in 1 patient because of mask discomfort (2.5%; confidence interval [CI], 0.1%-13.2%). This event was considered patient tolerance failure. The SGD generated accurately gated PET/CT images, with more than 95% of the breathing cycle detected and high temporal resolution, in 34 of the 39 patients (87.2%; 95% CI, 60.0%-100.0%) and failed to generate a biologic tumor volume in 1 of 21 patients with increased18 F-FDG uptake (4.8%; 95% CI, 0.1%-26.5%). The quality and accuracy of respiratory signal detection and synchronization were significantly better than those obtained with RPM ( P < 0.05). Conclusion: This trial supports the use of an SGD for gated lung PET/CT because of its high patient tolerance and accuracy. Although this technique seems to technically outperform RPM for gated PET/CT, further assessment of its superiority and the clinical benefit is warranted. We believe that this technique could be used as a gold standard to develop innovative approaches to eliminate respiration-induced blurring artifacts., (© 2019 by the Society of Nuclear Medicine and Molecular Imaging.)- Published
- 2019
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.