RTHP-17. APPLICATION OF EXACTRAC X-RAY IMAGE GUIDE SYSTEM IN STEREOTACTIC RADIOSURGERY FOR INTRACRANIAL NEURAL TUMORS IN PATIENTS AGED 3–14 YEARS

Abstract

Abstract OBJECTIVES To investigate the setup accuracy in stereotactic radiosurgery based on Exactrac Xray image guide system for intracranial neural tumors in patients aged between 3 and 14 years, and to discuss the related influence factors. METHODS Thirty seven patients with intracranial neural tumors, at the age of 314 years old, who were admitted to Guangdong Sanjiu Brain Hospital between March 2017 to January 2019 were enrolled in this study. After automatic setup with infrared markers, Exactrac Xray image guide system was applied to obtain the image of bilateral oblique intersection field, which were then registered with the field image digitally reconstructed with planning system, so as to obtain the translational errors in LAT (X), LNG (Y), VRT (Z) directions and the corresponding rotational errors. RESULTS After the positioning with Exactrac Xray image guide system and sixdimensional couch, the translational errors of all 37 patients in LAT, LNG, VRT directions were (0.26±0.13), (0.17±0.13), (0.15±0.11) mm, respectively, and the corresponding rotational errors were 0.21°±0.15°, 0.18°±0.15°, 0.18°±0.14°, respectively. The space vector error was (0.32±0.16) mm; translational errors were all less than 0.5 mm; rotational errors were all less than 0.5°. All of these errors were less than specified values and in accordance with the requirements of SRS. CONCLUSION Using Exactrac Xray image guide system and sixdimensional couch can remarkably improve the accuracy of SRS for intracranial neural tumors in patients aged 314 years. Exactrac Xray image guide system is worthy of application in the clinic.