73 results on '"Zahlmann, G."'
Search Results
52. Delivering a Quantitative Imaging Agenda.
- Author
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deSouza NM, van der Lugt A, Hall TJ, Sullivan D, and Zahlmann G
- Abstract
In a digital image, each voxel contains quantitative information dependent on the technique used to generate the image [...].
- Published
- 2023
- Full Text
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53. Application of the Lugano Classification for Initial Evaluation, Staging, and Response Assessment of Hodgkin and Non-Hodgkin Lymphoma: The PRoLoG Consensus Initiative (Part 2-Technical).
- Author
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Ricard F, Barrington S, Korn R, Brueggenwerth G, Trotman J, Cheson B, Salles G, Schwartz L, Goldmacher G, Jarecha R, Narang J, Broussais F, Galette P, Liu M, Bajpai S, Perlman E, Gillis J, Smalberg I, Terve P, Zahlmann G, and Schmid A
- Subjects
- Humans, Positron Emission Tomography Computed Tomography, Consensus, Neoplasm Staging, Fluorodeoxyglucose F18, Lymphoma, Non-Hodgkin diagnostic imaging, Lymphoma, Non-Hodgkin pathology, Lymphoma pathology
- Abstract
The aim of this initiative was to provide consensus recommendations from a consortium of academic and industry experts in the field of lymphoma and imaging for the consistent application of imaging assessment with the Lugano classification. Methods: Consensus was obtained through a series of meetings from July 2019 to October 2021 sponsored by the PINTaD (Pharma Imaging Network for Therapeutics and Diagnostics) as part of the ProLoG ( P INTaD R esp O nse criteria in L ymphoma w O rking G roup) consensus initiative. Results: Consensus recommendations encompass all technical imaging aspects of the Lugano classification. Some technical considerations for PET/CT and diagnostic CT are clarified with regards to required imaging series and scan visits, as well as acquisition and reconstruction of PET images and influence of lesion size and background activity. Recommendations are given on the role of imaging and clinical reviewers as well as on training and monitoring. Finally, an example template of an imaging case report form is provided to support efficient collection of data with Lugano Classification. Conclusion: Consensus recommendations are made to comprehensively address technical and imaging areas of inconsistency and ambiguity in the classification encountered by end users. Such guidance should be used to support standardized acquisition and evaluation with the Lugano 2014., (© 2023 by the Society of Nuclear Medicine and Molecular Imaging.)
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- 2023
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54. Application of the Lugano Classification for Initial Evaluation, Staging, and Response Assessment of Hodgkin and Non-Hodgkin Lymphoma: The PRoLoG Consensus Initiative (Part 1-Clinical).
- Author
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Ricard F, Cheson B, Barrington S, Trotman J, Schmid A, Brueggenwerth G, Salles G, Schwartz L, Goldmacher G, Jarecha R, Narang J, Broussais F, Galette P, Liu M, Bajpai S, Perlman E, Gillis J, Smalberg I, Terve P, Zahlmann G, and Korn R
- Subjects
- Humans, Positron Emission Tomography Computed Tomography, Consensus, Neoplasm Staging, Fluorodeoxyglucose F18, Lymphoma, Non-Hodgkin diagnostic imaging, Lymphoma, Non-Hodgkin pathology, Lymphoma pathology
- Abstract
Our objective was to provide consensus recommendations from a consortium of academic and industry experts in the field of lymphoma and imaging for consistent application of the Lugano classification. Methods: Consensus was obtained through a series of meetings from July 2019 until September 2021 sponsored by the Pharma Imaging Network for Therapeutics and Diagnostics (PINTaD) as part of the PINTaD Response Criteria in Lymphoma Working Group (PRoLoG) consensus initiative. Results: Consensus recommendations clarified technical considerations for PET/CT and diagnostic CT from the Lugano classification, including updating the FDG avidity of different lymphoma entities, clarifying the response nomenclature, and refining lesion classification and scoring, especially with regard to scores 4 and 5 and the X category of the 5-point scale. Combination of metabolic and anatomic responses is clarified, as well as response assessment in cases of discordant or missing evaluations. Use of clinical data in the classification, especially the requirement for bone marrow assessment, is further updated on the basis of lymphoma entities. Clarification is provided with regard to spleen and liver measurements and evaluation, as well as nodal response. Conclusion: Consensus recommendations are made to comprehensively address areas of inconsistency and ambiguity in the classification encountered during response evaluation by end users, and such guidance should be used as a companion to the 2014 Lugano classification., (© 2023 by the Society of Nuclear Medicine and Molecular Imaging.)
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- 2023
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55. MRI and Molecular Characterization of Pediatric High-Grade Midline Thalamic Gliomas: The HERBY Phase II Trial.
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Rodriguez D, Calmon R, Aliaga ES, Warren D, Warmuth-Metz M, Jones C, Mackay A, Varlet P, Le Deley MC, Hargrave D, Cañete A, Massimino M, Azizi AA, Saran F, Zahlmann G, Garcia J, Vassal G, Grill J, Peet A, Dineen RA, Morgan PS, and Jaspan T
- Subjects
- Child, Female, Histones genetics, Humans, Magnetic Resonance Imaging, Mutation genetics, Prospective Studies, Thalamus pathology, Brain Neoplasms diagnostic imaging, Brain Neoplasms genetics, Brain Neoplasms pathology, Glioma diagnostic imaging, Glioma genetics, Glioma pathology
- Abstract
Background Diffuse midline gliomas (DMG) are characterized by a high incidence of H3 K27 mutations and poorer outcome. The HERBY trial has provided one of the largest cohorts of pediatric DMGs with available radiologic, histologic-genotypic, and survival data. Purpose To define MRI and molecular characteristics of DMG. Materials and Methods This study is a secondary analysis of a prospective trial (HERBY; ClinicalTrials.gov identifier, NCT01390948) undertaken between October 2011 and February 2016. Among 121 HERBY participants, 50 had midline nonpontine-based tumors. Midline high-grade gliomas were reclassified into DMG H3 K27 mutant, H3 wild type with enhancer of zest homologs inhibitory protein overexpression, epidermal growth factor receptormutant, or not otherwise stated. The epicenter of each tumor and other radiologic characteristics were ascertained from MRI and correlated with the new subtype classification, histopathologic characteristics, surgical extent, and outcome parameters. Kaplan-Meier curves and log-rank tests were applied to determine and describe survival differences between groups. Results There were 42 participants (mean age, 12 years ± 4 [SD]; 23 girls) with radiologically evaluable thalamic-based DMG. Eighteen had partial thalamic involvement (12 thalamopulvinar, six anteromedial), 10 involved a whole thalamus, nine had unithalamic tumors with diffuse contiguous extension, and five had bithalamic tumors (two symmetric, three partial). Twenty-eight participants had DMG H3 K27 mutant tumors; there were no differences in outcome compared with other DMGs ( n = 4). Participants who underwent major debulking or total or near-total resection had longer overall survival (OS): 18.5 months vs 11.4 months ( P = .02). Enrolled participants who developed leptomeningeal metastatic dissemination before starting treatment had worse outcomes (event-free survival, 2.9 months vs 8.0 months [ P = .02]; OS, 11.4 months vs 18.5 months [ P = .004]). Conclusion Thalamic involvement of diffuse midline gliomas ranged from localized partial thalamic to holo- or bithalamic with diffuse contiguous spread and had poor outcomes, irrespective of H3 K27 subtype alterations. Leptomeningeal dissemination and less than 50% surgical resection were adverse risk factors for survival. Clinical trial registration no. NCT01390948 © RSNA, 2022 Online supplemental material is available for this article . See also the editorial by Widjaja in this issue.
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- 2022
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56. Radiological Evaluation of Newly Diagnosed Non-Brainstem Pediatric High-Grade Glioma in the HERBY Phase II Trial.
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Rodriguez Gutierrez D, Jones C, Varlet P, Mackay A, Warren D, Warmuth-Metz M, Aliaga ES, Calmon R, Hargrave DR, Cañete A, Massimino M, Azizi AA, Le Deley MC, Saran F, Rousseau RF, Zahlmann G, Garcia J, Vassal G, Grill J, Morgan PS, and Jaspan T
- Subjects
- Adolescent, Bevacizumab administration & dosage, Brain Neoplasms diagnostic imaging, Brain Neoplasms genetics, Brain Neoplasms therapy, Child, Child, Preschool, Combined Modality Therapy, Female, Glioma diagnostic imaging, Glioma genetics, Glioma therapy, Histones genetics, Humans, Male, Mutation, Neoplasm Grading, Neoplasm Recurrence, Local diagnostic imaging, Neoplasm Recurrence, Local genetics, Neoplasm Recurrence, Local therapy, Retrospective Studies, Survival Rate, Temozolomide administration & dosage, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Brain Neoplasms pathology, Chemoradiotherapy mortality, Glioma pathology, Neoplasm Recurrence, Local pathology, Neurosurgical Procedures mortality
- Abstract
Purpose: The HERBY trial evaluated the benefit of the addition of the antiangiogenic agent Bevacizumab (BEV) to radiotherapy/temozolomide (RT/TMZ) in pediatric patients with newly diagnosed non-brainstem high-grade glioma (HGG). The work presented here aims to correlate imaging characteristics and outcome measures with pathologic and molecular data., Experimental Design: Radiological, pathologic, and molecular data were correlated with trial clinical information to retrospectively re-evaluate event-free survival (EFS) and overall survival (OS)., Results: One-hundred thirteen patients were randomized to the RT/TMZ arm ( n = 54) or the RT/TMZ+BEV (BEV arm; n = 59). The tumor arose in the cerebral hemispheres in 68 patients (Cerebral group) and a midline location in 45 cases (Midline group). Pathologic diagnosis was available in all cases and molecular data in 86 of 113. H3 K27M histone mutations were present in 23 of 32 Midline cases and H3 G34R/V mutations in 7 of 54 Cerebral cases. Total/near-total resection occurred in 44 of 68 (65%) Cerebral cases but in only 5 of 45 (11%) Midline cases ( P < 0.05). Leptomeningeal metastases (27 cases, 13 with subependymal spread) at relapse were more frequent in Midline (17/45) than in Cerebral tumors (10/68, P < 0.05). Mean OS (14.1 months) and EFS (9.0 months) in Midline tumors were significantly lower than mean OS (20.7 months) and EFS (14.9 months) in Cerebral tumors ( P < 0.05). Pseudoprogression occurred in 8 of 111 (6.2%) cases., Conclusions: This study has shown that the poor outcome of midline tumors (compared with cerebral) may be related to (1) lesser surgical resection, (2) H3 K27M histone mutations, and (3) higher leptomeningeal dissemination., (©2020 American Association for Cancer Research.)
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- 2020
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57. Evaluation of the Implementation of the Response Assessment in Neuro-Oncology Criteria in the HERBY Trial of Pediatric Patients with Newly Diagnosed High-Grade Gliomas.
- Author
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Rodriguez D, Chambers T, Warmuth-Metz M, Aliaga ES, Warren D, Calmon R, Hargrave D, Garcia J, Vassal G, Grill J, Zahlmann G, Morgan PS, and Jaspan T
- Subjects
- Bevacizumab therapeutic use, Brain Stem Neoplasms pathology, Brain Stem Neoplasms therapy, Chemoradiotherapy methods, Child, Disease Progression, Disease-Free Survival, Female, Glioma pathology, Glioma therapy, Humans, Male, Multicenter Studies as Topic methods, Randomized Controlled Trials as Topic methods, Temozolomide therapeutic use, Brain Stem Neoplasms diagnostic imaging, Clinical Trials, Phase II as Topic methods, Glioma diagnostic imaging, Multimodal Imaging methods, Neuroimaging
- Abstract
Background and Purpose: HERBY was a Phase II multicenter trial setup to establish the efficacy and safety of adding bevacizumab to radiation therapy and temozolomide in pediatric patients with newly diagnosed non-brain stem high-grade gliomas. This study evaluates the implementation of the radiologic aspects of HERBY., Materials and Methods: We analyzed multimodal imaging compliance rates and scan quality for participating sites, adjudication rates and reading times for the central review process, the influence of different Response Assessment in Neuro-Oncology criteria in the final response, the incidence of pseudoprogression, and the benefit of incorporating multimodal imaging into the decision process., Results: Multimodal imaging compliance rates were the following: diffusion, 82%; perfusion, 60%; and spectroscopy, 48%. Neuroradiologists' responses differed for 50% of scans, requiring adjudication, with a total average reading time per patient of approximately 3 hours. Pseudoprogression occurred in 10/116 (9%) cases, 8 in the radiation therapy/temozolomide arm and 2 in the bevacizumab arm ( P < .01). Increased target enhancing lesion diameter was a reason for progression in 8/86 cases (9.3%) but never the only radiologic or clinical reason. Event-free survival was predicted earlier in 5/86 (5.8%) patients by multimodal imaging (diffusion, n = 4; perfusion, n = 1)., Conclusions: The addition of multimodal imaging to the response criteria modified the assessment in a small number of cases, determining progression earlier than structural imaging alone. Increased target lesion diameter, accounting for a large proportion of reading time, was never the only reason to designate disease progression., (© 2019 by American Journal of Neuroradiology.)
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- 2019
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58. Quantification of antiangiogenic treatment effects on tissue heterogeneity in glioma tumour xenograft model using a combination of DCE-MRI and 3D-ultramicroscopy.
- Author
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Dominietto M, Dobosz M, Bürgi S, Renner A, Zahlmann G, Scheuer W, and Rudin M
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- Animals, Brain Neoplasms drug therapy, Cell Line, Tumor, Glioma drug therapy, Heterografts, Humans, Mice, Neoplasms, Experimental, Neovascularization, Pathologic drug therapy, Neovascularization, Pathologic pathology, Vascular Endothelial Growth Factor A antagonists & inhibitors, Angiogenesis Inhibitors therapeutic use, Brain Neoplasms pathology, Frontal Lobe, Glioma pathology, Imaging, Three-Dimensional, Magnetic Resonance Imaging methods, Microscopy methods
- Abstract
Objectives: This study aimed at assessing the effects of an anti-angiogenic treatment, which neutralises vascular endothelial growth factor (VEGF), on tumour heterogeneity., Methods: Murine glioma cells have been inoculated into the right brain frontal lobe of 16 mice. Anti-VEGF antibody was administered to a first group (n = 8), while a second group (n = 8) received a placebo. Magnetic resonance acquisitions, performed at days 10, 12, 15 and 23 following the implantation, allowed the derivation of a three-dimensional features dataset characterising tumour heterogeneity. Three-dimensional ultramicroscopy and standard histochemistry analysis have been performed to verify in vivo results., Results: Placebo-treated mice displayed a highly-vascularised area at the tumour periphery, a monolithic necrotic core and a chaotic dense vasculature across the entire tumour. In contrast, the B20-treated group did not show any highly vascularised regions and presents a fragmented necrotic core. A significant reduction of the number of vessel segments smaller than 17 μm has been observed. There was no difference in overall tumour volume and growth rate between the two groups., Conclusions: Region-specific analysis revealed that VEGF inhibition affects only: (1) highly angiogenic compartments expressing high levels of VEGF and characterised by small capillaries, and also (2) the formation and structure of necrotic regions. These effects appear to be transient and limited in time., Key Points: • VEGF inhibition affects only the highly angiogenic region and small capillaries network • VEGF inhibition is transient in time • Tumour volume is not affected by anti-angiogenic treatment • VEGF inhibition also influences the architecture of necrotic regions.
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- 2017
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59. Response Assessment in Pediatric Neuro-Oncology: Implementation and Expansion of the RANO Criteria in a Randomized Phase II Trial of Pediatric Patients with Newly Diagnosed High-Grade Gliomas.
- Author
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Jaspan T, Morgan PS, Warmuth-Metz M, Sanchez Aliaga E, Warren D, Calmon R, Grill J, Hargrave D, Garcia J, and Zahlmann G
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- Adolescent, Adult, Angiogenesis Inhibitors therapeutic use, Bevacizumab therapeutic use, Brain Neoplasms drug therapy, Brain Neoplasms pathology, Child, Disease Progression, Disease-Free Survival, Female, Glioma drug therapy, Glioma pathology, Humans, Magnetic Resonance Imaging, Male, Brain Neoplasms diagnostic imaging, Diffusion Magnetic Resonance Imaging methods, Glioma diagnostic imaging
- Abstract
Determination of tumor response to treatment in neuro-oncology is challenging, particularly when antiangiogenic agents are considered. Nontumoral factors (eg, blood-brain barrier disruption, edema, and necrosis) can alter contrast enhancement independent of true tumor response/progression. Furthermore, gliomas are often infiltrative, with nonenhancing components. In adults, the Response Assessment in Neuro-Oncology (RANO) criteria attempted to address these issues. No such guidelines exist yet for children. The ongoing randomized phase II trial, A Study of Avastin (bevacizumab) in Combination With Temolozomide (TMZ) and Radiotherapy in Paediatric and Adolescent Patients With High-Grade Glioma (HERBY), will establish the efficacy and safety of the antiangiogenic agent bevacizumab for the first-line treatment of newly diagnosed high-grade glioma in children (n = 121 patients, enrollment complete). The primary end point is event-free survival (tumor progression/recurrence by central review, second primary malignancy, or death). Determination of progression or response is based on predefined clinical and radiographic criteria, modeled on the RANO criteria and supported by expert pseudoprogression review and the use of standardized imaging protocols. The HERBY trial will also compare conventional MR imaging (T1-weighted and T2/fluid-attenuated inversion recovery sequences) with conventional MR imaging plus diffusion/perfusion imaging for response assessment. It is anticipated that HERBY will provide new insights into antiangiogenic-treated pediatric brain tumors. HERBY will also investigate the practicality of obtaining adequate quality diffusion/perfusion scans in a trial setting, and the feasibility of implementing standard imaging protocols across multiple sites. To date, 61/73 (83.6%) patients with available data have completed diffusion-weighted imaging (uptake of other nonconventional techniques has been limited). Harmonization of imaging protocols and techniques may improve the robustness of pediatric neuro-oncology studies and aid future trial comparability., (© 2016 by American Journal of Neuroradiology.)
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- 2016
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60. Tumor volume measurement error using computed tomography imaging in a phase II clinical trial in lung cancer.
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Henschke CI, Yankelevitz DF, Yip R, Archer V, Zahlmann G, Krishnan K, Helba B, and Avila R
- Abstract
To address the error introduced by computed tomography (CT) scanners when assessing volume and unidimensional measurement of solid tumors, we scanned a precision manufactured pocket phantom simultaneously with patients enrolled in a lung cancer clinical trial. Dedicated software quantified bias and random error in the [Formula: see text], and [Formula: see text] dimensions of a Teflon sphere and also quantified response evaluation criteria in solid tumors and volume measurements using both constant and adaptive thresholding. We found that underestimation bias was essentially the same for [Formula: see text], and [Formula: see text] dimensions using constant thresholding and had similar values for adaptive thresholding. The random error of these length measurements as measured by the standard deviation and coefficient of variation was 0.10 mm (0.65), 0.11 mm (0.71), and 0.59 mm (3.75) for constant thresholding and 0.08 mm (0.51), 0.09 mm (0.56), and 0.58 mm (3.68) for adaptive thresholding, respectively. For random error, however, [Formula: see text] lengths had at least a fivefold higher standard deviation and coefficient of variation than [Formula: see text] and [Formula: see text]. Observed [Formula: see text]-dimension error was especially high for some 8 and 16 slice CT models. Error in CT image formation, in particular, for models with low numbers of detector rows, may be large enough to be misinterpreted as representing either treatment response or disease progression.
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- 2016
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61. Meta-analysis of the technical performance of an imaging procedure: guidelines and statistical methodology.
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Huang EP, Wang XF, Choudhury KR, McShane LM, Gönen M, Ye J, Buckler AJ, Kinahan PE, Reeves AP, Jackson EF, Guimaraes AR, and Zahlmann G
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- Humans, Reproducibility of Results, Biomarkers, Diagnostic Imaging, Guidelines as Topic, Meta-Analysis as Topic, Research Design, Statistics as Topic
- Abstract
Medical imaging serves many roles in patient care and the drug approval process, including assessing treatment response and guiding treatment decisions. These roles often involve a quantitative imaging biomarker, an objectively measured characteristic of the underlying anatomic structure or biochemical process derived from medical images. Before a quantitative imaging biomarker is accepted for use in such roles, the imaging procedure to acquire it must undergo evaluation of its technical performance, which entails assessment of performance metrics such as repeatability and reproducibility of the quantitative imaging biomarker. Ideally, this evaluation will involve quantitative summaries of results from multiple studies to overcome limitations due to the typically small sample sizes of technical performance studies and/or to include a broader range of clinical settings and patient populations. This paper is a review of meta-analysis procedures for such an evaluation, including identification of suitable studies, statistical methodology to evaluate and summarize the performance metrics, and complete and transparent reporting of the results. This review addresses challenges typical of meta-analyses of technical performance, particularly small study sizes, which often causes violations of assumptions underlying standard meta-analysis techniques. Alternative approaches to address these difficulties are also presented; simulation studies indicate that they outperform standard techniques when some studies are small. The meta-analysis procedures presented are also applied to actual [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) test-retest repeatability data for illustrative purposes., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)
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- 2015
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62. Quantitative imaging biomarkers: a review of statistical methods for technical performance assessment.
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Raunig DL, McShane LM, Pennello G, Gatsonis C, Carson PL, Voyvodic JT, Wahl RL, Kurland BF, Schwarz AJ, Gönen M, Zahlmann G, Kondratovich MV, O'Donnell K, Petrick N, Cole PE, Garra B, and Sullivan DC
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- Bias, Clinical Trials as Topic, Humans, Reproducibility of Results, Terminology as Topic, Biomarkers, Diagnostic Imaging, Research Design, Statistics as Topic
- Abstract
Technological developments and greater rigor in the quantitative measurement of biological features in medical images have given rise to an increased interest in using quantitative imaging biomarkers to measure changes in these features. Critical to the performance of a quantitative imaging biomarker in preclinical or clinical settings are three primary metrology areas of interest: measurement linearity and bias, repeatability, and the ability to consistently reproduce equivalent results when conditions change, as would be expected in any clinical trial. Unfortunately, performance studies to date differ greatly in designs, analysis method, and metrics used to assess a quantitative imaging biomarker for clinical use. It is therefore difficult or not possible to integrate results from different studies or to use reported results to design studies. The Radiological Society of North America and the Quantitative Imaging Biomarker Alliance with technical, radiological, and statistical experts developed a set of technical performance analysis methods, metrics, and study designs that provide terminology, metrics, and methods consistent with widely accepted metrological standards. This document provides a consistent framework for the conduct and evaluation of quantitative imaging biomarker performance studies so that results from multiple studies can be compared, contrasted, or combined., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)
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- 2015
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63. Implementing Adjusted Imaging Metrics Within Roche With the Metrics Champion Consortium: Experiences and Outcome.
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McDonald A and Zahlmann G
- Abstract
Purpose: To implement adjusted performance imaging metrics on imaging clinical trials of a pharmaceutical company (Roche) in a business relationship with preferred imaging providers and to report on findings and lessons learned., Methods: In 2009 the Metrics Champion Consortium provided the first imaging metrics for use in clinical trials as industry consensus. Roche reviewed, adjusted, excluded, and extended these metrics and defined target values per metric in order to implement them in all clinical trials with 7 preferred providers., Results: Roche preferred providers were able to report on all 19 metrics (8 unchanged Metrics Champion Consortium, 7 adjusted, and 4 Roche defined). Seventy-three Roche studies over 27 months form the basis for reporting; data are provided as mean and standard deviation per disease area with number of studies and for all studies reported for the specific metric for all providers. Disease areas are oncology, central nervous system, and inflammation. Seventeen metrics have proven to be useful; 2 metrics did not provide sufficient information; and 4 metrics need adjustments of target values., Limitations: Imaging trial-related metrics are a new concept, and Roche and providers had to develop the same consistent understanding of content and how to report a specific metric. The 73 studies covered all phases and disease areas, which made it difficult at times to compare results., Conclusions: Imaging metrics in clinical trials are a useful tool in improving timeliness and quality of imaging data, enhancing trial processes, and governing sponsor/provider relationships. It increases the transparency in the business relationship and in the different clinical trial-related process steps. The use of metrics highlights critical topics, such as reading and adjudication, and enables parties to take actions to improve performance. Disease area-related reporting needs more data for specific improvements.
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- 2014
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64. Response assessment criteria for glioblastoma: practical adaptation and implementation in clinical trials of antiangiogenic therapy.
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Chinot OL, Macdonald DR, Abrey LE, Zahlmann G, Kerloëguen Y, and Cloughesy TF
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- Clinical Trials, Phase III as Topic, Disease Progression, Double-Blind Method, Humans, Magnetic Resonance Imaging, Outcome Assessment, Health Care methods, Randomized Controlled Trials as Topic, Angiogenesis Inhibitors therapeutic use, Brain Neoplasms drug therapy, Glioblastoma drug therapy, Outcome Assessment, Health Care standards
- Abstract
Since 1990, the primary criteria used for assessing response to therapy in high-grade gliomas were those developed by Macdonald and colleagues, which incorporated 2-dimensional area measurements of contrast-enhancing tumor regions, corticosteroid dosing, and clinical assessment to arrive at a designation of response, stable disease, or progression. Recent advances in imaging technology and targeted therapeutics, however, have exposed limitations of the Macdonald criteria and have highlighted the need for reevaluation of response assessment criteria. In 2010, the Response Assessment in Neuro-Oncology (RANO) Working Group published updated criteria to address this need and to standardize response assessment for high-grade gliomas. In 2009, prior to the publication of the RANO criteria, the randomized, placebo-controlled, multicenter, phase 3 AVAglio trial was designed and initiated to investigate the effectiveness of radiotherapy and temozolomide with or without bevacizumab in newly diagnosed glioblastoma. The AVAglio protocol enacted specific measures to adapt the Macdonald criteria to the frontline treatment setting and to antiangiogenic agent evaluation, including the incorporation of a T2/fluid-attenuated inversion recovery component, qualitative assessment of irregularly shaped contrast-enhancing lesions, and a decision tree for confirming or ruling out pseudoprogression. Moreover, the protocol outlines practical means by which these adapted response criteria can be implemented in the clinic. This article describes the evolution of radiographic response criteria for high-grade gliomas and highlights the similarities and differences between those implemented in the AVAglio study and those subsequently published by RANO.
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- 2013
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65. Quantitative imaging test approval and biomarker qualification: interrelated but distinct activities.
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Buckler AJ, Bresolin L, Dunnick NR, Sullivan DC, Aerts HJ, Bendriem B, Bendtsen C, Boellaard R, Boone JM, Cole PE, Conklin JJ, Dorfman GS, Douglas PS, Eidsaunet W, Elsinger C, Frank RA, Gatsonis C, Giger ML, Gupta SN, Gustafson D, Hoekstra OS, Jackson EF, Karam L, Kelloff GJ, Kinahan PE, McLennan G, Miller CG, Mozley PD, Muller KE, Patt R, Raunig D, Rosen M, Rupani H, Schwartz LH, Siegel BA, Sorensen AG, Wahl RL, Waterton JC, Wolf W, Zahlmann G, and Zimmerman B
- Subjects
- Biomedical Research organization & administration, Conflict of Interest, Device Approval, Europe, Humans, Predictive Value of Tests, United States, United States Food and Drug Administration, Biomarkers, Diagnostic Imaging, Diffusion of Innovation, Technology Assessment, Biomedical standards
- Abstract
Unlabelled: Quantitative imaging biomarkers could speed the development of new treatments for unmet medical needs and improve routine clinical care. However, it is not clear how the various regulatory and nonregulatory (eg, reimbursement) processes (often referred to as pathways) relate, nor is it clear which data need to be collected to support these different pathways most efficiently, given the time- and cost-intensive nature of doing so. The purpose of this article is to describe current thinking regarding these pathways emerging from diverse stakeholders interested and active in the definition, validation, and qualification of quantitative imaging biomarkers and to propose processes to facilitate the development and use of quantitative imaging biomarkers. A flexible framework is described that may be adapted for each imaging application, providing mechanisms that can be used to develop, assess, and evaluate relevant biomarkers. From this framework, processes can be mapped that would be applicable to both imaging product development and to quantitative imaging biomarker development aimed at increasing the effectiveness and availability of quantitative imaging., Supplemental Material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100800/-/DC1., (RSNA, 2011)
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- 2011
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66. MIPortal: a high capacity server for molecular imaging research.
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Pivovarov M, Bhandary G, Mahmood U, Zahlmann G, Naraghi M, and Weissleder R
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- Computer Security, Internet, Computational Biology instrumentation, Computational Biology methods, Diagnostic Imaging methods, Software
- Abstract
The introduction of novel molecular tools in research and clinical medicine has created a need for more refined information management systems. This article describes the design and implementation of such a new information platform: the Molecular Imaging Portal (MIPortal). The platform was created to organize, archive, and rapidly retrieve large datasets using Web-based browsers as access points. The system has been implemented in a heterogeneous, academic research environment serving Macintosh, Unix, and Microsoft Windows clients and has been shown to be extraordinarily robust and versatile. In addition, it has served as a useful tool for clinical trials and collaborative multi-institutional small-animal imaging research.
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- 2005
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67. Perioperative cataract OP management by means of teleconsultation.
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Zahlmann G, Mertz M, Fabian E, Holle R, Kaatz H, Neubauer L, Strobl H, and Walther HD
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- Feasibility Studies, Humans, Patient Satisfaction, Perioperative Care methods, Surveys and Questionnaires, Cataract therapy, Cataract Extraction, Ophthalmology methods, Remote Consultation methods
- Abstract
Background: Teleconsultation services have the potential to improve the communication among different medical care providers and between them and the patient. Increasing effectiveness in the shape of a savings in time or cost is often the result of better communication., Methods: A study was performed in order to demonstrate the feasibility of teleconsultation services, using the perioperative management of cataract patients as an example, and to provide data on the quality, acceptance and effectiveness of these services in comparison with a control group experiencing normal treatment., Results: Over a period of 3 months 42 patients of the teleconsultation group and 20 controls were studied. There were two referring ophthalmologists and three surgeons. The teleconsultation group had one consultation fewer with the ophthalmic surgeon because of the teleconsultation service. Patient satisfaction was slightly higher using the new technology. Patients would like to see this technique used again should surgery on the second eye become necessary., Conclusions: Teleconsultation services are ready to support and improve perioperative cataract management. Patients' confidence in their medical treatment was increased by using teleconsultation services. Physicians will expand the use of teleconsultation.
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- 2002
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68. Real applications of patient-related telemedical services.
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Zahlmann G, Obermaier M, and Mertz M
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- Humans, Information Services, Marketing of Health Services, Monitoring, Physiologic, Organizational Objectives, Patient Education as Topic, User-Computer Interface, Medical Informatics Applications, Patient-Centered Care organization & administration, Telemedicine organization & administration
- Published
- 2000
69. [Teleconsultation network for ophthalmology--experiences and results].
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Zahlmann G, Walther HD, Liesenfeld B, Kaatz H, Kluthe S, Fabian E, Klaas D, Schnarr KD, Neubauer L, Obermaier M, Wegner A, Mertz M, and Mann G
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- Computer Security legislation & jurisprudence, Computer Systems, Germany, Humans, Patient Care Team, Computer Communication Networks instrumentation, Ophthalmology instrumentation, Remote Consultation instrumentation
- Abstract
Motivation: Telemedical services for ophthalmology are developed within the OPHTEL project, which has been funded by the European Union and by the Bavarian government in the Bavaria-online initiative., Methods: Seven private ophthalmologists, one university eye clinic, one clinical Diabetes center and an informatics research institute are connected within a teleconsultation network. Asynchronous (based on Internet E-Mail) and synchronous (based on ISDN-mediated videoconferencing tools) types of teleconsultations are realized., Results: 86 teleconsultations (62 asynchronous, 23 synchronous) took place within the first 10 months. Complex and rare eye diseases as well as interdisciplinary questions (ophthalmology--diabetology) are the main area of medical communication interest. Legal and security problems are discussed., Conclusions: Telemedical services must be understood as a complete process of medical care on the basis of modern communication technologies, which influences also the management of this process.
- Published
- 1998
- Full Text
- View/download PDF
70. [Scientific role of German ophthalmology in the European telecommunication project OPHTEL].
- Author
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Mertz M, Mann G, Zahlmann G, and Obermaier M
- Subjects
- Europe, Germany, Humans, Medical Records Systems, Computerized instrumentation, Patient Care Team, Quality Control, Computer Communication Networks instrumentation, Ophthalmology instrumentation, Remote Consultation instrumentation
- Abstract
Background: In Denmark, France, Germany, Great Britain and Italy, the OPHTEL project combines clinical centers of ophthalmology and internal medicine, an institute for medical informatics and health services research, a publishing company and different industrial partners in the EDP market., Aims: With the aid of visual telecommunication and rapid data transfer, methods and conditions will be developed and proved so that any physician can very easily obtain sufficient information for treating his patient. Thus, the regional differences in the quality of structured health service (e.g., urban/ rural) will be overcome throughout Europe. SCIENTIFIC TASKS: A multilingual diagnostic and therapeutic thesaurus has to be worked out in order to create standards for communication and quality control. Based on literature, images and image analysis in a knowledge-based data bank, a monitoring system (containing watch-dog functions) and the basic aspects of an ophthalmological patient/disease register will be investigated. (In parallel, a technical development of synchronous and asynchronous telecommunication between eye physicians is taking place in close cooperation with the regional Bavarian project Teleopathalmology in Bavaria on-line)., Results: State of the art 6 months after starting the project:the knowledge-based image data bank has been founded and also an ophthalmological 8 language thesaurus and definition standard. All data transfer lines are installed., Discussion: The project is taking place amid diverging sections of medicine: ophthalmology and internal medicine, health politics and data protection, individual treatment and common interest (health care), product management and office organization. Thus, the scientific quality of the transferred ophthalmological content must undergo sophisticated controls. FUTURE STEPS: Intense cooperation with the big German associations for ophthalmology (DOG, BVA) and the European ophthalmological societies concerning EDP, classification and quality control.
- Published
- 1997
- Full Text
- View/download PDF
71. DIABETEX--a decision support system for therapy of type I diabetic patients.
- Author
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Zahlmann G, Franczykova M, Henning G, Strube M, Hüttl I, Hummel I, and Bruns W
- Subjects
- Adolescent, Child, Decision Support Techniques, Diabetes Mellitus, Type 1 metabolism, Drug Administration Schedule, Female, Glycated Hemoglobin metabolism, Humans, Insulin administration & dosage, Male, Middle Aged, Retrospective Studies, Software Design, Diabetes Mellitus, Type 1 therapy, Expert Systems, Software, Therapy, Computer-Assisted
- Abstract
DIABETEX is a knowledge-based, computer-supported consultation system for the therapy of type I diabetic out-patients. Three knowledge bases contain the medical and technical knowledge for treating either adults, adolescents or children by means of injections or by pumps. For the evaluation of the quality of the decision proposals three groups of patients were studied. The results obtained in test phase 1, i.e. the retrospective evaluation of DIABETEX decision proposals by the experts, and in test phase 2, i.e. the parallel work of DIABETEX and of an expert and the subsequent evaluation by experts, provide the basis for the further development and application of the system by non-expert diabetologists.
- Published
- 1990
- Full Text
- View/download PDF
72. [Application of information technology in orthodontics. 6. Knowledge based systems in orthodontics].
- Author
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Reinhardt H, Haffner T, Ifert F, Malsch J, Schneider P, and Zahlmann G
- Subjects
- Diagnosis, Computer-Assisted, Humans, Microcomputers, Therapy, Computer-Assisted, Databases, Factual, Expert Systems, Orthodontics
- Abstract
The increase of quality and efficiency in orthodontic treatment is characterized by the development of knowledge based consultations systems. These systems support the dentist to optimate treatment planing. Basis configuration and technical background of those systems are presented.
- Published
- 1990
73. [Galvanic primary cell as a basic sensor for the GOD-glucose electrode].
- Author
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Zahlmann G and Lemke K
- Subjects
- Cell Membrane Permeability, Electrodes, Electrolytes metabolism, Glucose Oxidase metabolism, Humans, Oxygen metabolism, Blood Glucose analysis
- Published
- 1986
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