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Lasbleiz J.,University of Rennes 1 | Morelli J.,Texas A&M University | Schnel N.,University of Rennes 1 | Burgun A.,University of Rennes 1 | And 4 more authors.
Studies in Health Technology and Informatics | Year: 2012

Magnetic Resonance Imaging is an essential diagnostic imaging technique. The complexity of interpreting MRI images is often compounded by the presence of a wide range of artifacts which are often challenging to identify and eliminate. Ontology permits the construction of a knowledge database with which users can interact given an appropriate interface. The goal of this work is to create an interactive tool for the ontology of MRI artifacts that will allow a radiologist to compare any given MRI artifact image with those contained in the ontology. Material and method: Using Protégé 4, we have constructed the ontology with input from an expert in MRI artifacts and utilizing images exemplifying such artifacts. The graphical user interface has been built in Java and the linkage with the ontology made with Owl API. Results: Using the tool, users can compare imaging artifacts encountered in daily practice to those in the database. Once a user has identified the image the most similar to their own, they then have instantaneous access to the knowledge contained in the ontology about the artifact. Individual users can also submit images and have access to DICOM data. © 2012 European Federation for Medical Informatics and IOS Press. All rights reserved.

Eliat P.-A.,PRiSM | Olivie D.,University of Rennes 1 | Olivie D.,Rennes University Hospital Center | Saikali S.,Rennes University Hospital Center | And 5 more authors.
Neurology Research International | Year: 2012

An interesting approach has been proposed to differentiate malignant glioneuronal tumors (MGNTs) as a subclass of the WHO grade III and IV malignant gliomas. MGNT histologically resemble any WHO grade III or IV glioma but have a different biological behavior, presenting a survival twice longer as WHO glioblastomas and a lower occurrence of metastases. However, neurofilament protein immunostaining was required for identification of MGNT. Using two complementary methods, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and texture analysis (MRI-TA) from the same acquisition process, the challenge is to in vivo identify MGNT and demonstrate that MRI postprocessing could contribute to a better typing and grading of glioblastoma. Results are obtained on a preliminary group of 19 patients a posteriori selected for a blind investigation of DCE T1-weighted and TA at 1.5 T. The optimal classification (0/11 misclassified MGNT) is obtained by combining the two methods, DCE-MRI and MRI-TA. © 2012 Pierre-Antoine Eliat et al.

Bahri H.,Cancer Institute Eugene Marquis | Laurence L.,Cancer Institute Eugene Marquis | Laurence L.,French Institute of Health and Medical Research | Laurence L.,University of Rennes 1 | And 15 more authors.
Journal of Nuclear Medicine | Year: 2014

This study aimed to evaluate the long-term prognostic usefulness of 18F-FDG PET for patients with metastatic gastroenteropancreatic neuroendocrine tumors (GEPNETs). Methods: Thirty-eight patients with metastatic GEPNETs were prospectively enrolled. Initial check-up comprised CT scan, 111In-pentetreotide scintigraphy (SRS), and 18F-FDG PET. Only 18F-FDG PET-positive lesions with a maximum standardized uptake value (SUVmax) greater than 4.5 or an SUV ratio (SUVmax tumor to SUVmax nontumoral liver tissue, or T/NT ratio) of 2.5 or greater were considered positive for prognosis-that is, indicating a poor prognosis. Progressionfree survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Factors associated with survival were assessed with univariate and multivariate analyses, using the Cox regression model. Results: Median PFS and OS were significantly higher for patients with a negative 18F-FDG PET finding, with an OS of 119.5 mo (95% confidence interval [CI], 72-∞), than for patients with a positive 18F-FDG PET finding (only 15 mo [95% CI, 4-27]) (P , 10-3). Median PFS and OS were significantly higher for the patient group that had a positive SRS than the group with a negative SRS (P 5 0.0002). For patients with a positive SRS, PFS and OS were significantly shorter when the 18F-FDG PET finding was positive: 19.5 mo (95% CI, 4-37) for PFS and 119.5 mo (95% CI, 81-∞) for OS (P , 10-3). In the patient group with a lowgrade GEPNET and a positive SRS, PFS and OS were also significantly lower for patients with a positive 18F-FDG PET. At 48-mo follow-up, 100% of patients who had a positive 18F-FDG PET for disease progression (of which 47% were also SRS-positive) were deceased, and 87% of patients with a negative 18F-FDG PET were alive (P , 0.0001). The T/NT ratio was the only parameter associated with OS on multivariate analysis. Conclusion: Overall, 18FFDG PET appears to be of major importance in the prognostic evaluation of metastatic GEPNET. A positive 18F-FDG PET with an SV ratio (T/NT) of 2.5 or greater was a poor prognostic factor, with a 4-y survival rate of 0%. A positive SRS does not eliminate the need for performing 18F-FDG PET, which is of greater prognostic utility. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Garin E.,Cancer Institute Eugene Marquis | Garin E.,University of Rennes 1 | Garin E.,French Institute of Health and Medical Research | Rolland Y.,Cancer Institute Eugene Marquis | And 21 more authors.
Journal of Nuclear Medicine | Year: 2015

The objective of this study was to evaluate the response rate and survival of hepatocellular carcinoma portal vein thrombosis (PVT) patients treated with 90Y-loaded glass microspheres using a personalized dosimetry and intensification concept. Methods: The microspheres were administered to 41 hepatocellular carcinoma PVT patients (main = 12; lobar/segmental = 29). 99mTc-macroaggregated albumin SPECT/CT quantitative analysis was used to calculate the tumor dose (TD), healthy injected liver dose (HILD), and injected liver dose (ILD). Response was evaluated at 3 mo using the criteria of the European Association for the Study of the Liver, with CT follow-up lasting until disease progression or death. Survival was assessed using the Kaplan-Meier method. Results: The mean injected activity was 3.1 ± 1.5 GBq, and mean ILD was 143 ± 49 Gy. When a TD threshold of 205 Gy was applied, 99mTc-macroaggregated albumin SPECT/CT achieved a 100% sensitivity and 90% overall accuracy (0 false-negatives; 4 false-positives) in response prediction. On the basis of TD and HILD values, 37% of patients received an intensification of the treatment (increased injected activity with the aim of achieving a TD ≥ 205 Gy and HILD < 120 Gy, applying an ILD > 150 Gy). This intensification resulted in a high response rate (85%) without increased liver toxicity of grade 3 or higher (6% vs. 12% in the patients who did not receive treatment intensification; not statistically significant). For the total 41 patients, median overall survival (OS) was 18 mo (95% confidence interval, 11-25 mo). For patients with a TD of less than 205 Gy, median OS was 4.3 mo (3.7-5 mo), versus 18.2 mo (8.5-28.7 mo) for those with a TD of 205 Gy or more (P = 0.005). Median OS was 20.9 mo for patients with a TD of 205 Gy or more and good PVT targeting (n = 36). OS was 12 mo (3 mo to ∞) for patients with main PVT, versus 21.5 mo (12-28.7 mo) for those with segmental or lobar PVT (not statistically significant). For the 5 patients with complete portal vein revascularization who underwent lobar hepatectomy, median OS was not reached yet exceeded 24.5 mo and was significantly higher than that of other patients (P = 0.0493). Conclusion: Using a 99mTc-macro-aggregated albumin SPECT/CT personalized dosimetry and intensification concept with 90Y-loaded glass microspheres induced prolonged OS for PVT patients as compared with the standard of care (sorafenib), without increasing liver toxicity. Prospective randomized studies are therefore warranted. Copyright © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Garin E.,Cancer Institute Eugene Marquis | Garin E.,University of Rennes 1 | Garin E.,French Institute of Health and Medical Research | Rolland Y.,Cancer Institute Eugene Marquis | And 4 more authors.
European Journal of Nuclear Medicine and Molecular Imaging | Year: 2016

Radioembolization with 90Y-loaded microspheres is increasingly used in the treatment of primary and secondary liver cancer. Technetium-99 m macroaggregated albumin (MAA) scintigraphy is used as a surrogate of microsphere distribution to assess lung or digestive shunting prior to therapy, based on tumoral targeting and dosimetry. To date, this has been the sole pre-therapeutic tool available for such evaluation. Several dosimetric approaches have been described using both glass and resin microspheres in hepatocellular carcinoma (HCC) and liver metastasis. Given that each product offers different specific activities and numbers of spheres injected, their radiobiological properties are believed to lightly differ. This paper summarizes and discusses the available studies focused on MAA-based dosimetry, particularly concentrating on potential confounding factors like clinical context, tumor size, cirrhosis, previous or concomitant therapy, and product used. In terms of the impact of tumoral dose in HCC, the results were concordant and a response relationship and tumoral threshold dose was clearly identified, especially in studies using glass microspheres. Tumoral dose has also been found to influence survival. The concept of treatment intensification has recently been introduced, yet despite several studies publishing interesting findings on the tumor dose-metastasis relationship, no consensus has been reached, and further clarification is thus required. Nor has the maximal tolerated dose to the liver been well documented, requiring more accurate evaluation. Lung dose was well described, despite recently identified factors influencing its evaluation, requiring further assessment. Conclusion: MAA SPECT/CT dosimetry is accurate in HCC and can now be used in order to achieve a fully customized approach, including treatment intensification. Yet further studies are warranted for the metastasis setting and evaluating the maximal tolerated liver dose. © 2015, The Author(s).

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