MRI-Related Geometric Distortions in Stereotactic Radiotherapy Treatment Planning: Evaluation and Dosimetric Impact
| العنوان: | MRI-Related Geometric Distortions in Stereotactic Radiotherapy Treatment Planning: Evaluation and Dosimetric Impact |
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| المؤلفون: | Eleftherios P. Pappas, Evangelos Georgiou, A. Moutsatsos, Hani Lababidi, K. Alsafi, Konstantinos Georgiou, Mukhtar Alshanqity, Pantelis Karaiskos |
| المصدر: | Technology in Cancer Research & Treatment |
| بيانات النشر: | SAGE Publications, 2017. |
| سنة النشر: | 2017 |
| مصطلحات موضوعية: | Cancer Research, Computer science, medicine.medical_treatment, stereotactic radiosurgery, geometric distortion, Radiosurgery, Imaging phantom, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Neuroimaging, Neoplasms, Distortion, medicine, Humans, spatial accuracy, Radiation treatment planning, medicine.diagnostic_test, Phantoms, Imaging, business.industry, Brain, Isocenter, DVH, Radiotherapy Dosage, Magnetic resonance imaging, Original Articles, Magnetic Resonance Imaging, Radiation therapy, spatial uncertainty, Oncology, 030220 oncology & carcinogenesis, stereotactic radiotherapy, Tomography, X-Ray Computed, Nuclear medicine, business, MRI |
| الوصف: | In view of their superior soft tissue contrast compared to computed tomography, magnetic resonance images are commonly involved in stereotactic radiosurgery/radiotherapy applications for target delineation purposes. It is known, however, that magnetic resonance images are geometrically distorted, thus deteriorating dose delivery accuracy. The present work focuses on the assessment of geometric distortion inherent in magnetic resonance images used in stereotactic radiosurgery/radiotherapy treatment planning and attempts to quantitively evaluate the consequent impact on dose delivery. The geometric distortions for 3 clinical magnetic resonance protocols (at both 1.5 and 3.0 T) used for stereotactic radiosurgery/radiotherapy treatment planning were evaluated using a recently proposed phantom and methodology. Areas of increased distortion were identified at the edges of the imaged volume which was comparable to a brain scan. Although mean absolute distortion did not exceed 0.5 mm on any spatial axis, maximum detected control point disposition reached 2 mm. In an effort to establish what could be considered as acceptable geometric uncertainty, highly conformal plans were utilized to irradiate targets of different diameters (5-50 mm). The targets were mispositioned by 0.5 up to 3 mm, and dose–volume histograms and plan quality indices clinically used for plan evaluation and acceptance were derived and used to investigate the effect of geometrical uncertainty (distortion) on dose delivery accuracy and plan quality. The latter was found to be strongly dependent on target size. For targets less than 20 mm in diameter, a spatial disposition of the order of 1 mm could significantly affect (>5%) plan acceptance/quality indices. For targets with diameter greater than 2 cm, the corresponding disposition was found greater than 1.5 mm. Overall results of this work suggest that efficacy of stereotactic radiosurgery/radiotherapy applications could be compromised in case of very small targets lying distant from the scanner’s isocenter (eg, the periphery of the brain). |
| تدمد: | 1533-0338 1533-0346 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a6e195135897808b2ea20d12e0c87e4bTest https://doi.org/10.1177/1533034617735454Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....a6e195135897808b2ea20d12e0c87e4b |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15330338 15330346 |
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