Objective The aim of the study was to compare the dose to lung volume in the supine and prone posi- tion while designing CyberKnife treatment plans to treat metastatic tumors in the spinous processes of the thoracic v...Objective The aim of the study was to compare the dose to lung volume in the supine and prone posi- tion while designing CyberKnife treatment plans to treat metastatic tumors in the spinous processes of the thoracic vertebrae, and offer a reference for reducing damage to normal tissues. Methods Nine cases of metastatic tumors in the spinous processes of the thoracic vertebrae were selected, and then we designed treatment plans based on the supine and prone positions and compared the results. Results In contrast with the treatment plan based on the prone position, the one for the supine position required 14862-36337 MU more; the lung D5% was 5.20-7.90 Gy higher; and the lung D20% was 2.61-5.73 Gy higher. The difference of dose to spine volume between the two plans was -2.21-2.67 Gy; to the skin volume was -3.93-7.85 Gy; and to the esophagus was 0.28-6.39 Gy. Conclusion The treatment plan based on the prone position of patients can better protect lung tissues than the one based on the supine position, and can also improve the avaUabilitv of beams.展开更多
基金Supported by a grant of 2013 the General Logistics Department Military Logistic Research Project Key Programs(No.BWS13J031)
文摘Objective The aim of the study was to compare the dose to lung volume in the supine and prone posi- tion while designing CyberKnife treatment plans to treat metastatic tumors in the spinous processes of the thoracic vertebrae, and offer a reference for reducing damage to normal tissues. Methods Nine cases of metastatic tumors in the spinous processes of the thoracic vertebrae were selected, and then we designed treatment plans based on the supine and prone positions and compared the results. Results In contrast with the treatment plan based on the prone position, the one for the supine position required 14862-36337 MU more; the lung D5% was 5.20-7.90 Gy higher; and the lung D20% was 2.61-5.73 Gy higher. The difference of dose to spine volume between the two plans was -2.21-2.67 Gy; to the skin volume was -3.93-7.85 Gy; and to the esophagus was 0.28-6.39 Gy. Conclusion The treatment plan based on the prone position of patients can better protect lung tissues than the one based on the supine position, and can also improve the avaUabilitv of beams.
