The Experts below are selected from a list of 20013 Experts worldwide ranked by ideXlab platform

Juanita Crook - One of the best experts on this subject based on the ideXlab platform.

  • establishing a simulation based education program for radiation oncology learners in permanent seed implant brachytherapy building validation evidence
    Brachytherapy, 2020
    Co-Authors: Michael Roumeliotis, Michelle Hilts, Juanita Crook, Sarah Quirk, Siraj Husain, Elizabeth Watt, Alexandra Guebert, Amy Frederick, Kevin Martell, Deidre Batchelar
    Abstract:

    Abstract Purpose The purpose of this study was to establish a simulation-based education program for radiation oncology learners in permanent seed implant brachytherapy. The first step in formalizing any education program is a validation process that builds evidence-based verification that the learning environment is appropriate. Methods and Materials The primary education task allowed practitioners to use an anthropomorphic breast phantom to simulate a permanent seed implant brachytherapy delivery. Validation evidence is built by generating data to assess learner and expert cohorts according to their proficiency. Each practitioner's performance during the simulation was evaluated by seed Placement Accuracy, procedural time-to-complete, and two qualitative evaluation tools—a global rating scale and procedural checklist. Results The average seed Placement Accuracy (±SD) was 8.1 ± 3.5 mm compared to 6.1 ± 2.6 mm for the learner and expert cohort, respectively. The median (range) procedural time-to-complete was 64 (60–77) minutes and 43 (41–50) minutes for the learner and expert cohort, respectively. Seed Placement Accuracy (student t-test, p  Conclusions This validation evidence supports the utilization of this simulation environment toward appropriately capturing the delivery experience of practitioners. The results demonstrate that, in all areas of evaluation, expert cohort proficiency was superior to learner cohort proficiency. This methodology will be used to establish a simulation-based education program for radiation oncology learners in permanent seed implant brachytherapy.

  • seroma visualization and implant Accuracy in permanent breast seed implant brachytherapy
    Practical radiation oncology, 2019
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Juanita Crook
    Abstract:

    Abstract Purpose This study aimed to evaluate the relationship between seroma visualization and seed Placement Accuracy in permanent breast seed implant brachytherapy (PBSI). Methods and materials At the time of planning computed tomography (CT), 10 patients receiving PBSI were imaged with spatially co-registered 3-dimensional ultrasound (US). Seromas were independently contoured by 3 radiation oncologists on CT and US scans. Intra- and interuser conformity indices (CIs) were used as a surrogate for seroma visualization. Intermodality visualization differences were assessed by defining consensus contours, clinical target volume (CTV)CT and CTVUS, and evaluating the CI and the centroid position and volume differences. Seed Placement Accuracy was represented by the differences between the planned and implanted seed positions (disPlacements). Correlations among total, systematic, and random seed disPlacements and seroma visualization metrics were assessed. Results The median (range) intra-user CI of CT seroma contouring was 0.60 (0.46-0.72), and the median interuser CIs were 0.46 (0.38-0.58) and 0.50 (0.29-0.67) on CT and US, respectively. The CTVUS was a mean 68% ± 12% smaller than CTVCT and differed in centroid position by 8 ± 3 mm. Seeds were placed, on average, 10 ± 5 mm from their planned positions, and intrapatient systematic disPlacements were observed. The mean seed disPlacements for the implants were shown to correlate with interuser CI on CT (r = .74; P = .01) and volume differences between CTVCT and CTVUS (r = .65; P = .04), but not with intrauser CI, intermodality CI or centroid differences. Systematic disPlacements were correlated with interuser CT CI (r = .67; P = .03) and intermodality volume difference (r = .64; P = .04), but random seed disPlacements were independent of all evaluated metrics. Conclusions Consistency in seroma delineation in treatment planning and differences between seroma visualized on CT and US scans are associated with seed Placement Accuracy in PBSI. Efforts to enhance seroma visualization in treatment planning and implant guidance may have a positive impact on treatment quality and should be pursued to facilitate the widespread implementation of this technique.

  • sci thur pm brachytherapy 03 identifying the impact of seroma visualization on permanent breast seed implant brachytherapy
    Medical Physics, 2016
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Sarah Lucas, Juanita Crook
    Abstract:

    Purpose: Uncertainties in target identification can reduce treatment Accuracy in permanent breast seed implant (PBSI) brachytherapy. This study evaluates the relationship between seroma visualization and seed Placement Accuracy. Methods: Spatially co-registered CT and 3D ultrasound (US) images were acquired for 10 patients receiving PBSI. Seromas were retrospectively contoured independently by 3 radiation oncologists on both CT and US and respective consensus volumes were defined, CTVCT and CTVUS. The seroma clarity and inter-user conformity index (CI), as well as inter-modality CI, volume, and positional differences were evaluated. Correlations with seed Placement Accuracy were then assessed. CTVs were expanded by 1.25cm to create PTVCT and PTVUS and evaluate the conformity with PTVClinical (CTVClinical+1.25cm) used in treatment planning. The change in PTV coincidence by expanding PTVClinical by 0.25cm was determined. Results: CTVUS were a mean 68 ± 12% smaller than CTVCT and generally had improved clarity and inter-user conformity. No correlations between seed disPlacement and CTVUS-CTVCT positional difference or CI were observed. Greater seed disPlacements were associated with larger CTVUS-CTVCT volume differences (r=−0.65) and inter-user CT CI (r=−0.74). A median (range) 88% (71–99%) of PTVCT and 83% (69–100%) of PTVUS were contained within PTVClinical. Expanding treatment margins to 1.5cm increased coincidence to 98% (86–100%) and 94% (82–100%), respectively. Conclusions: Differences in seroma visualization impacts seed disPlacement in PBSI. Reducing dependence on CT by incorporating 3DUS into target identification, or expanding CT-based treatment margins to 1.5cm may reduce or mitigate uncertainties related to seroma visualization.

Michelle Hilts - One of the best experts on this subject based on the ideXlab platform.

  • establishing a simulation based education program for radiation oncology learners in permanent seed implant brachytherapy building validation evidence
    Brachytherapy, 2020
    Co-Authors: Michael Roumeliotis, Michelle Hilts, Juanita Crook, Sarah Quirk, Siraj Husain, Elizabeth Watt, Alexandra Guebert, Amy Frederick, Kevin Martell, Deidre Batchelar
    Abstract:

    Abstract Purpose The purpose of this study was to establish a simulation-based education program for radiation oncology learners in permanent seed implant brachytherapy. The first step in formalizing any education program is a validation process that builds evidence-based verification that the learning environment is appropriate. Methods and Materials The primary education task allowed practitioners to use an anthropomorphic breast phantom to simulate a permanent seed implant brachytherapy delivery. Validation evidence is built by generating data to assess learner and expert cohorts according to their proficiency. Each practitioner's performance during the simulation was evaluated by seed Placement Accuracy, procedural time-to-complete, and two qualitative evaluation tools—a global rating scale and procedural checklist. Results The average seed Placement Accuracy (±SD) was 8.1 ± 3.5 mm compared to 6.1 ± 2.6 mm for the learner and expert cohort, respectively. The median (range) procedural time-to-complete was 64 (60–77) minutes and 43 (41–50) minutes for the learner and expert cohort, respectively. Seed Placement Accuracy (student t-test, p  Conclusions This validation evidence supports the utilization of this simulation environment toward appropriately capturing the delivery experience of practitioners. The results demonstrate that, in all areas of evaluation, expert cohort proficiency was superior to learner cohort proficiency. This methodology will be used to establish a simulation-based education program for radiation oncology learners in permanent seed implant brachytherapy.

  • seroma visualization and implant Accuracy in permanent breast seed implant brachytherapy
    Practical radiation oncology, 2019
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Juanita Crook
    Abstract:

    Abstract Purpose This study aimed to evaluate the relationship between seroma visualization and seed Placement Accuracy in permanent breast seed implant brachytherapy (PBSI). Methods and materials At the time of planning computed tomography (CT), 10 patients receiving PBSI were imaged with spatially co-registered 3-dimensional ultrasound (US). Seromas were independently contoured by 3 radiation oncologists on CT and US scans. Intra- and interuser conformity indices (CIs) were used as a surrogate for seroma visualization. Intermodality visualization differences were assessed by defining consensus contours, clinical target volume (CTV)CT and CTVUS, and evaluating the CI and the centroid position and volume differences. Seed Placement Accuracy was represented by the differences between the planned and implanted seed positions (disPlacements). Correlations among total, systematic, and random seed disPlacements and seroma visualization metrics were assessed. Results The median (range) intra-user CI of CT seroma contouring was 0.60 (0.46-0.72), and the median interuser CIs were 0.46 (0.38-0.58) and 0.50 (0.29-0.67) on CT and US, respectively. The CTVUS was a mean 68% ± 12% smaller than CTVCT and differed in centroid position by 8 ± 3 mm. Seeds were placed, on average, 10 ± 5 mm from their planned positions, and intrapatient systematic disPlacements were observed. The mean seed disPlacements for the implants were shown to correlate with interuser CI on CT (r = .74; P = .01) and volume differences between CTVCT and CTVUS (r = .65; P = .04), but not with intrauser CI, intermodality CI or centroid differences. Systematic disPlacements were correlated with interuser CT CI (r = .67; P = .03) and intermodality volume difference (r = .64; P = .04), but random seed disPlacements were independent of all evaluated metrics. Conclusions Consistency in seroma delineation in treatment planning and differences between seroma visualized on CT and US scans are associated with seed Placement Accuracy in PBSI. Efforts to enhance seroma visualization in treatment planning and implant guidance may have a positive impact on treatment quality and should be pursued to facilitate the widespread implementation of this technique.

  • sci thur pm brachytherapy 03 identifying the impact of seroma visualization on permanent breast seed implant brachytherapy
    Medical Physics, 2016
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Sarah Lucas, Juanita Crook
    Abstract:

    Purpose: Uncertainties in target identification can reduce treatment Accuracy in permanent breast seed implant (PBSI) brachytherapy. This study evaluates the relationship between seroma visualization and seed Placement Accuracy. Methods: Spatially co-registered CT and 3D ultrasound (US) images were acquired for 10 patients receiving PBSI. Seromas were retrospectively contoured independently by 3 radiation oncologists on both CT and US and respective consensus volumes were defined, CTVCT and CTVUS. The seroma clarity and inter-user conformity index (CI), as well as inter-modality CI, volume, and positional differences were evaluated. Correlations with seed Placement Accuracy were then assessed. CTVs were expanded by 1.25cm to create PTVCT and PTVUS and evaluate the conformity with PTVClinical (CTVClinical+1.25cm) used in treatment planning. The change in PTV coincidence by expanding PTVClinical by 0.25cm was determined. Results: CTVUS were a mean 68 ± 12% smaller than CTVCT and generally had improved clarity and inter-user conformity. No correlations between seed disPlacement and CTVUS-CTVCT positional difference or CI were observed. Greater seed disPlacements were associated with larger CTVUS-CTVCT volume differences (r=−0.65) and inter-user CT CI (r=−0.74). A median (range) 88% (71–99%) of PTVCT and 83% (69–100%) of PTVUS were contained within PTVClinical. Expanding treatment margins to 1.5cm increased coincidence to 98% (86–100%) and 94% (82–100%), respectively. Conclusions: Differences in seroma visualization impacts seed disPlacement in PBSI. Reducing dependence on CT by incorporating 3DUS into target identification, or expanding CT-based treatment margins to 1.5cm may reduce or mitigate uncertainties related to seroma visualization.

Deidre Batchelar - One of the best experts on this subject based on the ideXlab platform.

  • establishing a simulation based education program for radiation oncology learners in permanent seed implant brachytherapy building validation evidence
    Brachytherapy, 2020
    Co-Authors: Michael Roumeliotis, Michelle Hilts, Juanita Crook, Sarah Quirk, Siraj Husain, Elizabeth Watt, Alexandra Guebert, Amy Frederick, Kevin Martell, Deidre Batchelar
    Abstract:

    Abstract Purpose The purpose of this study was to establish a simulation-based education program for radiation oncology learners in permanent seed implant brachytherapy. The first step in formalizing any education program is a validation process that builds evidence-based verification that the learning environment is appropriate. Methods and Materials The primary education task allowed practitioners to use an anthropomorphic breast phantom to simulate a permanent seed implant brachytherapy delivery. Validation evidence is built by generating data to assess learner and expert cohorts according to their proficiency. Each practitioner's performance during the simulation was evaluated by seed Placement Accuracy, procedural time-to-complete, and two qualitative evaluation tools—a global rating scale and procedural checklist. Results The average seed Placement Accuracy (±SD) was 8.1 ± 3.5 mm compared to 6.1 ± 2.6 mm for the learner and expert cohort, respectively. The median (range) procedural time-to-complete was 64 (60–77) minutes and 43 (41–50) minutes for the learner and expert cohort, respectively. Seed Placement Accuracy (student t-test, p  Conclusions This validation evidence supports the utilization of this simulation environment toward appropriately capturing the delivery experience of practitioners. The results demonstrate that, in all areas of evaluation, expert cohort proficiency was superior to learner cohort proficiency. This methodology will be used to establish a simulation-based education program for radiation oncology learners in permanent seed implant brachytherapy.

  • seroma visualization and implant Accuracy in permanent breast seed implant brachytherapy
    Practical radiation oncology, 2019
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Juanita Crook
    Abstract:

    Abstract Purpose This study aimed to evaluate the relationship between seroma visualization and seed Placement Accuracy in permanent breast seed implant brachytherapy (PBSI). Methods and materials At the time of planning computed tomography (CT), 10 patients receiving PBSI were imaged with spatially co-registered 3-dimensional ultrasound (US). Seromas were independently contoured by 3 radiation oncologists on CT and US scans. Intra- and interuser conformity indices (CIs) were used as a surrogate for seroma visualization. Intermodality visualization differences were assessed by defining consensus contours, clinical target volume (CTV)CT and CTVUS, and evaluating the CI and the centroid position and volume differences. Seed Placement Accuracy was represented by the differences between the planned and implanted seed positions (disPlacements). Correlations among total, systematic, and random seed disPlacements and seroma visualization metrics were assessed. Results The median (range) intra-user CI of CT seroma contouring was 0.60 (0.46-0.72), and the median interuser CIs were 0.46 (0.38-0.58) and 0.50 (0.29-0.67) on CT and US, respectively. The CTVUS was a mean 68% ± 12% smaller than CTVCT and differed in centroid position by 8 ± 3 mm. Seeds were placed, on average, 10 ± 5 mm from their planned positions, and intrapatient systematic disPlacements were observed. The mean seed disPlacements for the implants were shown to correlate with interuser CI on CT (r = .74; P = .01) and volume differences between CTVCT and CTVUS (r = .65; P = .04), but not with intrauser CI, intermodality CI or centroid differences. Systematic disPlacements were correlated with interuser CT CI (r = .67; P = .03) and intermodality volume difference (r = .64; P = .04), but random seed disPlacements were independent of all evaluated metrics. Conclusions Consistency in seroma delineation in treatment planning and differences between seroma visualized on CT and US scans are associated with seed Placement Accuracy in PBSI. Efforts to enhance seroma visualization in treatment planning and implant guidance may have a positive impact on treatment quality and should be pursued to facilitate the widespread implementation of this technique.

  • sci thur pm brachytherapy 03 identifying the impact of seroma visualization on permanent breast seed implant brachytherapy
    Medical Physics, 2016
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Sarah Lucas, Juanita Crook
    Abstract:

    Purpose: Uncertainties in target identification can reduce treatment Accuracy in permanent breast seed implant (PBSI) brachytherapy. This study evaluates the relationship between seroma visualization and seed Placement Accuracy. Methods: Spatially co-registered CT and 3D ultrasound (US) images were acquired for 10 patients receiving PBSI. Seromas were retrospectively contoured independently by 3 radiation oncologists on both CT and US and respective consensus volumes were defined, CTVCT and CTVUS. The seroma clarity and inter-user conformity index (CI), as well as inter-modality CI, volume, and positional differences were evaluated. Correlations with seed Placement Accuracy were then assessed. CTVs were expanded by 1.25cm to create PTVCT and PTVUS and evaluate the conformity with PTVClinical (CTVClinical+1.25cm) used in treatment planning. The change in PTV coincidence by expanding PTVClinical by 0.25cm was determined. Results: CTVUS were a mean 68 ± 12% smaller than CTVCT and generally had improved clarity and inter-user conformity. No correlations between seed disPlacement and CTVUS-CTVCT positional difference or CI were observed. Greater seed disPlacements were associated with larger CTVUS-CTVCT volume differences (r=−0.65) and inter-user CT CI (r=−0.74). A median (range) 88% (71–99%) of PTVCT and 83% (69–100%) of PTVUS were contained within PTVClinical. Expanding treatment margins to 1.5cm increased coincidence to 98% (86–100%) and 94% (82–100%), respectively. Conclusions: Differences in seroma visualization impacts seed disPlacement in PBSI. Reducing dependence on CT by incorporating 3DUS into target identification, or expanding CT-based treatment margins to 1.5cm may reduce or mitigate uncertainties related to seroma visualization.

Daniel Morton - One of the best experts on this subject based on the ideXlab platform.

  • seroma visualization and implant Accuracy in permanent breast seed implant brachytherapy
    Practical radiation oncology, 2019
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Juanita Crook
    Abstract:

    Abstract Purpose This study aimed to evaluate the relationship between seroma visualization and seed Placement Accuracy in permanent breast seed implant brachytherapy (PBSI). Methods and materials At the time of planning computed tomography (CT), 10 patients receiving PBSI were imaged with spatially co-registered 3-dimensional ultrasound (US). Seromas were independently contoured by 3 radiation oncologists on CT and US scans. Intra- and interuser conformity indices (CIs) were used as a surrogate for seroma visualization. Intermodality visualization differences were assessed by defining consensus contours, clinical target volume (CTV)CT and CTVUS, and evaluating the CI and the centroid position and volume differences. Seed Placement Accuracy was represented by the differences between the planned and implanted seed positions (disPlacements). Correlations among total, systematic, and random seed disPlacements and seroma visualization metrics were assessed. Results The median (range) intra-user CI of CT seroma contouring was 0.60 (0.46-0.72), and the median interuser CIs were 0.46 (0.38-0.58) and 0.50 (0.29-0.67) on CT and US, respectively. The CTVUS was a mean 68% ± 12% smaller than CTVCT and differed in centroid position by 8 ± 3 mm. Seeds were placed, on average, 10 ± 5 mm from their planned positions, and intrapatient systematic disPlacements were observed. The mean seed disPlacements for the implants were shown to correlate with interuser CI on CT (r = .74; P = .01) and volume differences between CTVCT and CTVUS (r = .65; P = .04), but not with intrauser CI, intermodality CI or centroid differences. Systematic disPlacements were correlated with interuser CT CI (r = .67; P = .03) and intermodality volume difference (r = .64; P = .04), but random seed disPlacements were independent of all evaluated metrics. Conclusions Consistency in seroma delineation in treatment planning and differences between seroma visualized on CT and US scans are associated with seed Placement Accuracy in PBSI. Efforts to enhance seroma visualization in treatment planning and implant guidance may have a positive impact on treatment quality and should be pursued to facilitate the widespread implementation of this technique.

  • sci thur pm brachytherapy 03 identifying the impact of seroma visualization on permanent breast seed implant brachytherapy
    Medical Physics, 2016
    Co-Authors: Daniel Morton, Michelle Hilts, Deidre Batchelar, Audrey Tetreaultlaflamme, Benjamin Mou, Sarah Lucas, Juanita Crook
    Abstract:

    Purpose: Uncertainties in target identification can reduce treatment Accuracy in permanent breast seed implant (PBSI) brachytherapy. This study evaluates the relationship between seroma visualization and seed Placement Accuracy. Methods: Spatially co-registered CT and 3D ultrasound (US) images were acquired for 10 patients receiving PBSI. Seromas were retrospectively contoured independently by 3 radiation oncologists on both CT and US and respective consensus volumes were defined, CTVCT and CTVUS. The seroma clarity and inter-user conformity index (CI), as well as inter-modality CI, volume, and positional differences were evaluated. Correlations with seed Placement Accuracy were then assessed. CTVs were expanded by 1.25cm to create PTVCT and PTVUS and evaluate the conformity with PTVClinical (CTVClinical+1.25cm) used in treatment planning. The change in PTV coincidence by expanding PTVClinical by 0.25cm was determined. Results: CTVUS were a mean 68 ± 12% smaller than CTVCT and generally had improved clarity and inter-user conformity. No correlations between seed disPlacement and CTVUS-CTVCT positional difference or CI were observed. Greater seed disPlacements were associated with larger CTVUS-CTVCT volume differences (r=−0.65) and inter-user CT CI (r=−0.74). A median (range) 88% (71–99%) of PTVCT and 83% (69–100%) of PTVUS were contained within PTVClinical. Expanding treatment margins to 1.5cm increased coincidence to 98% (86–100%) and 94% (82–100%), respectively. Conclusions: Differences in seroma visualization impacts seed disPlacement in PBSI. Reducing dependence on CT by incorporating 3DUS into target identification, or expanding CT-based treatment margins to 1.5cm may reduce or mitigate uncertainties related to seroma visualization.

Alexander Opitz - One of the best experts on this subject based on the ideXlab platform.

  • on the importance of precise electrode Placement for targeted transcranial electric stimulation
    NeuroImage, 2018
    Co-Authors: Alexander Opitz, Erin M Yeagle, Axel Thielscher, Charles E Schroeder, Ashesh D Mehta, Michael P Milham
    Abstract:

    Abstract Transcranial electric stimulation (TES) is an increasingly popular method for non-invasive modulation of brain activity and a potential treatment for neuropsychiatric disorders. However, there are concerns about the reliability of its application because of variability in TES-induced intracranial electric fields across individuals. While realistic computational models offer can help to alleviate these concerns, their direct empirical validation is sparse, and their practical implications are not always clear. In this study, we combine direct intracranial measurements of electric fields generated by TES in surgical epilepsy patients with computational modeling. First, we directly validate the computational models and identify key parameters needed for accurate model predictions. Second, we derive practical guidelines for a reliable application of TES in terms of the precision of electrode Placement needed to achieve a desired electric field distribution. Based on our results, we recommend electrode Placement Accuracy to be