7 results on '"Maeder, Philippe"'
Search Results
2. Complete washout of a colloid cyst on MRI after partial removal by endoscopic approach.
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Robert, Thomas, Maeder, Philippe, Levivier, Marc, and Pollo, Claudio
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CYSTS (Pathology) , *SURGERY , *ENDOSCOPY , *CEREBRAL ventricles , *COLLOIDS , *HEADACHE , *HYDROCEPHALUS , *MAGNETIC resonance imaging , *TOMOGRAPHY , *DIAGNOSIS - Abstract
A letter to the editor is presented which is concerned with a patient who had a complete washout of a colloid cyst on a magnetic resonance imaging test after partial removal by endoscopic approach.
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- 2012
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3. Multi-channel MRI segmentation of eye structures and tumors using patient-specific features.
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Ciller, Carlos, De Zanet, Sandro, Kamnitsas, Konstantinos, Maeder, Philippe, Glocker, Ben, Munier, Francis L., Rueckert, Daniel, Thiran, Jean-Philippe, Bach Cuadra, Meritxell, and Sznitman, Raphael
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RETINOBLASTOMA , *MELANOMA diagnosis , *EYE , *IMAGE segmentation , *RADIOTHERAPY treatment planning , *DIAGNOSIS , *MAGNETIC resonance imaging - Abstract
Retinoblastoma and uveal melanoma are fast spreading eye tumors usually diagnosed by using 2D Fundus Image Photography (Fundus) and 2D Ultrasound (US). Diagnosis and treatment planning of such diseases often require additional complementary imaging to confirm the tumor extend via 3D Magnetic Resonance Imaging (MRI). In this context, having automatic segmentations to estimate the size and the distribution of the pathological tissue would be advantageous towards tumor characterization. Until now, the alternative has been the manual delineation of eye structures, a rather time consuming and error-prone task, to be conducted in multiple MRI sequences simultaneously. This situation, and the lack of tools for accurate eye MRI analysis, reduces the interest in MRI beyond the qualitative evaluation of the optic nerve invasion and the confirmation of recurrent malignancies below calcified tumors. In this manuscript, we propose a new framework for the automatic segmentation of eye structures and ocular tumors in multi-sequence MRI. Our key contribution is the introduction of a pathological eye model from which Eye Patient-Specific Features (EPSF) can be computed. These features combine intensity and shape information of pathological tissue while embedded in healthy structures of the eye. We assess our work on a dataset of pathological patient eyes by computing the Dice Similarity Coefficient (DSC) of the sclera, the cornea, the vitreous humor, the lens and the tumor. In addition, we quantitatively show the superior performance of our pathological eye model as compared to the segmentation obtained by using a healthy model (over 4% DSC) and demonstrate the relevance of our EPSF, which improve the final segmentation regardless of the classifier employed. [ABSTRACT FROM AUTHOR]
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- 2017
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4. MRI-based assessment of the pineal gland in a large population of children aged 0-5 years and comparison with pineoblastoma: part II, the cystic gland.
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Sirin, Selma, Jong, Marcus, Galluzzi, Paolo, Maeder, Philippe, Brisse, Hervé, Castelijns, Jonas, Graaf, Pim, and Goericke, Sophia
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BRAIN , *RADIOGRAPHY , *PINEAL gland tumors , *ANTHROPOMETRY , *COMPARATIVE studies , *MAGNETIC resonance imaging , *MEDICAL cooperation , *PINEAL gland , *REGRESSION analysis , *RESEARCH , *RETINOBLASTOMA , *RETROSPECTIVE studies , *DESCRIPTIVE statistics , *CHILDREN , *DIAGNOSIS , *ANATOMY - Abstract
Introduction: Pineal cysts are a common incidental finding on brain MRI with resulting difficulties in differentiation between normal glands and pineal pathologies. The aim of this study was to assess the size and morphology of the cystic pineal gland in children (0-5 years) and compare the findings with published pineoblastoma cases. Methods: In this retrospective multicenter study, 257 MR examinations (232 children, 0-5 years) were evaluated regarding pineal gland size (width, height, planimetric area, maximal cyst(s) size) and morphology. We performed linear regression analysis with 99 % prediction intervals of gland size versus age for the size parameters. Results were compared with a recent meta-analysis of pineoblastoma by de Jong et al. Results: Follow-up was available in 25 children showing stable cystic findings in 48 %, cyst size increase in 36 %, and decrease in 16 %. Linear regression analysis gave 99 % upper prediction bounds of 10.8 mm, 10.9 mm, 7.7 mm and 66.9 mm, respectively, for cyst size, width, height, and area. The slopes (size increase per month) of each parameter were 0.030, 0.046, 0.021, and 0.25, respectively. Most of the pineoblastomas showed a size larger than the 99 % upper prediction margin, but with considerable overlap between the groups. Conclusion: We presented age-adapted normal values for size and morphology of the cystic pineal gland in children aged 0 to 5 years. Analysis of size is helpful in discriminating normal glands from cystic pineal pathologies such as pineoblastoma. We also presented guidelines for the approach of a solid or cystic pineal gland in hereditary retinoblastoma patients. [ABSTRACT FROM AUTHOR]
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- 2016
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5. MRI-based assessment of the pineal gland in a large population of children aged 0-5 years and comparison with pineoblastoma: part I, the solid gland.
- Author
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Galluzzi, Paolo, Jong, Marcus, Sirin, Selma, Maeder, Philippe, Piu, Pietro, Cerase, Alfonso, Monti, Lucia, Brisse, Hervé, Castelijns, Jonas, Graaf, Pim, and Goericke, Sophia
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BRAIN , *RADIOGRAPHY , *PINEAL gland tumors , *AGE distribution , *ANTHROPOMETRY , *COMPARATIVE studies , *CONFIDENCE intervals , *MAGNETIC resonance imaging , *PINEAL gland , *REGRESSION analysis , *RETINOBLASTOMA , *SEX distribution , *RETROSPECTIVE studies , *DESCRIPTIVE statistics , *CHILDREN , *DIAGNOSIS , *ANATOMY - Abstract
Introduction: Differentiation between normal solid (non-cystic) pineal glands and pineal pathologies on brain MRI is difficult. The aim of this study was to assess the size of the solid pineal gland in children (0-5 years) and compare the findings with published pineoblastoma cases. Methods: We retrospectively analyzed the size (width, height, planimetric area) of solid pineal glands in 184 non-retinoblastoma patients (73 female, 111 male) aged 0-5 years on MRI. The effect of age and gender on gland size was evaluated. Linear regression analysis was performed to analyze the relation between size and age. Ninety-nine percent prediction intervals around the mean were added to construct a normal size range per age, with the upper bound of the predictive interval as the parameter of interest as a cutoff for normalcy. Results: There was no significant interaction of gender and age for all the three pineal gland parameters (width, height, and area). Linear regression analysis gave 99 % upper prediction bounds of 7.9, 4.8, and 25.4 mm, respectively, for width, height, and area. The slopes (size increase per month) of each parameter were 0.046, 0.023, and 0.202, respectively. Ninety-three percent (95 % CI 66-100 %) of asymptomatic solid pineoblastomas were larger in size than the 99 % upper bound. Conclusion: This study establishes norms for solid pineal gland size in non-retinoblastoma children aged 0-5 years. Knowledge of the size of the normal pineal gland is helpful for detection of pineal gland abnormalities, particularly pineoblastoma. [ABSTRACT FROM AUTHOR]
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- 2016
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6. High-Resolution Magnetic Resonance Imaging Can Reliably Detect Orbital Tumor Recurrence after Enucleation in Children with Retinoblastoma.
- Author
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Sirin, Selma, de Jong, Marcus C., de Graaf, Pim, Brisse, Hervé J., Galluzzi, Paolo, Maeder, Philippe, Bornfeld, Norbert, Biewald, Eva, Metz, Klaus A., Temming, Petra, Castelijns, Jonas A., and Goericke, Sophia L.
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RETINOBLASTOMA , *ENUCLEATION of the eye , *EYE , *CANCER relapse , *SURGICAL complications , *DIAGNOSIS , *MAGNETIC resonance imaging , *THERAPEUTICS - Abstract
Purpose Orbital tumor recurrence is a rare but serious complication in children with retinoblastoma, leading to a high risk of metastasis and death. Therefore, we assume that these recurrences have to be detected and treated as early as possible. Preliminary studies used magnetic resonance imaging (MRI) to evaluate postsurgical findings in the orbit. In this study, we assessed the diagnostic accuracy of high-resolution MRI to detect orbital tumor recurrence in children with retinoblastoma in a large study cohort. Design Consecutive retrospective study (2007–2013) assessing MRI findings after enucleation. Participants A total of 103 MRI examinations of 55 orbits (50 children, 27 male/23 female, mean age 16.3±12.4 months) with a median time of 8 months (range, 0–93) after enucleation for retinoblastoma. Methods High-resolution MRI using orbital surface coils was performed on 1.5 Tesla MRI systems to assess abnormal orbital findings. Main Outcome Measures Five European experts in retinoblastoma imaging evaluated the MRI examinations regarding the presence of abnormal orbital gadolinium enhancement and judged them as “definitive tumor,” “suspicious of tumor,” “postsurgical condition/scar formation,” or “without pathologic findings.” The findings were correlated to histopathology (if available), MRI, and clinical follow-up. Results Abnormal orbital enhancement was a common finding after enucleation (100% in the first 3 months after enucleation, 64.3% >3 years after enucleation). All histopathologically confirmed tumor recurrences (3 of 55 orbits, 5.5%) were correctly judged as “definitive tumor” in MRI. Two orbits from 2 children rated as “suspicious of tumor” received intravenous chemotherapy without histopathologic confirmation; further follow-up (67 and 47 months) revealed no sign of tumor recurrence. In 90.2%, no tumor was suspected on MRI, which was clinically confirmed during follow-up (median follow-up after enucleation, 45 months; range, 8–126). Conclusions High-resolution MRI with orbital surface coils may reliably distinguish between common postsurgical contrast enhancement and orbital tumor recurrence, and therefore may be a useful tool to evaluate orbital tumor recurrence after enucleation in children with retinoblastoma. We recommend high-resolution MRI as a potential screening tool for the orbit in children with retinoblastoma to exclude tumor recurrence, especially in high-risk patients within the critical first 2 years after enucleation. [ABSTRACT FROM AUTHOR]
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- 2016
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7. Visualizing the Skip Lesions of Giant Cell Arteritis with CT Arteriography.
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Kawasaki, Aki, Michel, Patrik, Maeder, Philippe, and Borruat, François-Xavier
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GIANT cell arteritis , *ARTERITIS , *TOMOGRAPHY , *ANGIOGRAPHY , *DISEASES in older people , *BIOPSY , *DIAGNOSIS - Abstract
The article presents the case of a 77-year-old man who was doubted to have a giant cell arteritis after developing headaches, jaw claudication and diplopia. The man underwent a computed tomography (CT) angiography of the extracranial arteries and has revealed luminal narrowing and mural thickening with skip lesions inflammation along his right superficial temporal artery. It notes that the diagnosis of giant cell arteritis was proven after he had biopsy.
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- 2009
- Full Text
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