Robustness and precision of an automatic marker detection algorithm for online prostate daily targeting using a standard V-EPID
| Autor: | Eric Vigneault, Jean Pouliot, Jacques Laverdière, N. Martel-Brisson, Sylviane Aubin, René Roy, L.M. Girouard, S. Pouliot, Luc Beaulieu |
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| Rok vydání: | 2003 |
| Předmět: |
Male
Computer science medicine.medical_treatment Movement Iterative reconstruction Sensitivity and Specificity Pattern Recognition Automated Prostate medicine Medical imaging Dosimetry Humans Computed radiography Radiometry Image-guided radiation therapy Radiotherapy Planning Computer-Assisted Prostatic Neoplasms Radiotherapy Dosage General Medicine Radiation therapy medicine.anatomical_structure Radiographic Image Interpretation Computer-Assisted Tomography Tomography X-Ray Computed Algorithm Algorithms |
| Zdroj: | Medical physics. 30(7) |
| ISSN: | 0094-2405 |
| Popis: | An algorithm for the daily localization of the prostate using implanted markers and a standard video-based electronic portal imaging device (V-EPID) has been tested. Prior to planning, three gold markers were implanted in the prostate of seven patients. The clinical images were acquired with a BeamView Plus 2.1 V-EPID for each field during the normal course radiotherapy treatment and are used off-line to determine the ability of the automatic marker detection algorithm to adequately and consistently detect the markers. Clinical images were obtained with various dose levels from ranging 2.5 to 75 MU. The algorithm is based on marker attenuation characterization in the portal image and spatial distribution. A total of 1182 clinical images were taken. The results show an average efficiency of 93% for the markers detected individually and 85% for the group of markers. This algorithm accomplishes the detection and validation in 0.20–0.40 s. When the center of mass of the group of implanted markers is used, then all displacements can be corrected to within 1.0 mm in 84% of the cases and within 1.5 mm in 97% of cases. The standard video-based EPID tested provides excellent marker detection capability even with low dose levels. The V-EPID can be used successfully with radiopaque markers and the automatic detection algorithm to track and correct the daily setup deviations due to organ motions. |
| Databáze: | OpenAIRE |
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