We have located links that may give you full text access.
Seroma visualization and implant accuracy in permanent breast seed implant brachytherapy.
Practical Radiation Oncology 2019 January 12
PURPOSE: To evaluate the relationship between seroma visualization and seed placement accuracy in permanent breast seed implant brachytherapy (PBSI).
MATERIALS AND METHODS: At the time of planning CT, 10 patients receiving PBSI were imaged with spatially co-registered 3D ultrasound (US). Seromas were independently contoured by 3 radiation oncologists on CT and US. Intra- and inter-user conformity indices (CI) were used as a surrogate for seroma visualization. Inter-modality visualization differences were assessed by defining consensus contours, CTVCT and CTVUS , and evaluating the CI as well as centroid position and volume differences. Seed placement accuracy was represented by differences between the planned and implanted seed positions (displacements). Correlations between total, systematic, and random seed displacements and seroma visualization metrics were assessed.
RESULTS: Median (range) intra-user CI of CT seroma contouring was 0.60 (0.46-0.72), and median inter-user CI were 0.46 (0.38-0.58) and 0.50 (0.29-0.67) on CT and US, respectively. CTVUS were a mean 68±12% smaller than CTVCT , and differed in centroid position by 8±3mm. Seeds were placed, on average, 10±5mm from their planned positions, and intra-patient systematic displacements were observed. The mean seed displacements for the implants were shown to correlate with inter-user CI on CT (r=0.74, p=0.01), and volume differences between CTVCT and CTVUS (r=0.65, p=0.04), but not with intra-user CI, inter-modality CI or centroid differences. Systematic displacements were correlated with the inter-user CT CI (r=0.67, p=0.03) and inter-modality volume difference (r=0.64, p=0.04), 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 are associated with seed placement accuracy in PBSI. Efforts to enhance seroma visualization in treatment planning and implant guidance may have positive impact on treatment quality and should be pursued to facilitate widespread implementation of this technique.
MATERIALS AND METHODS: At the time of planning CT, 10 patients receiving PBSI were imaged with spatially co-registered 3D ultrasound (US). Seromas were independently contoured by 3 radiation oncologists on CT and US. Intra- and inter-user conformity indices (CI) were used as a surrogate for seroma visualization. Inter-modality visualization differences were assessed by defining consensus contours, CTVCT and CTVUS , and evaluating the CI as well as centroid position and volume differences. Seed placement accuracy was represented by differences between the planned and implanted seed positions (displacements). Correlations between total, systematic, and random seed displacements and seroma visualization metrics were assessed.
RESULTS: Median (range) intra-user CI of CT seroma contouring was 0.60 (0.46-0.72), and median inter-user CI were 0.46 (0.38-0.58) and 0.50 (0.29-0.67) on CT and US, respectively. CTVUS were a mean 68±12% smaller than CTVCT , and differed in centroid position by 8±3mm. Seeds were placed, on average, 10±5mm from their planned positions, and intra-patient systematic displacements were observed. The mean seed displacements for the implants were shown to correlate with inter-user CI on CT (r=0.74, p=0.01), and volume differences between CTVCT and CTVUS (r=0.65, p=0.04), but not with intra-user CI, inter-modality CI or centroid differences. Systematic displacements were correlated with the inter-user CT CI (r=0.67, p=0.03) and inter-modality volume difference (r=0.64, p=0.04), 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 are associated with seed placement accuracy in PBSI. Efforts to enhance seroma visualization in treatment planning and implant guidance may have positive impact on treatment quality and should be pursued to facilitate widespread implementation of this technique.
Full text links
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app