Study On Tumor Volume In Nasopharyngeal Carcinoma And Recurrence Of Nasopharyngeal Carcinoma By Image Fusion

Abstract Objective:To evaluate the influence of CT, MRI image fusion technology for delineation of volumes and dose distribution of nasopharyngeal carcinoma(NPC). Methods:Ten case of nasopharyngeal carcinoma, histologically diagnosed and received enhenced CT and MRI scans nasopharynx were enrolled in this study. Two Images transmitted to planning systems. Make image fusion on the use of the image fusion software on workstation, and use LandMark as the registration methods. senior radiotherapy doctors and Deputy Director physician of radiology in our hospital will make evaluation and sketching for registration. Three radiotherapy doctors who have enough experience respectively outlined the gross target volume in every layer in CT and MRI image. Compare the three groups, which were outlined by doctor A B C, we selected the people who outlined the smallest difference between GTVCT and GTVMRI. Make the radiotherapy plan, to evaluate the radiation dosimetry, target volume and critical organ at risk were outlined in en cases according to CT nd MRI image. Conelusions:(1) MRI was superior to CT in demonstrating lesions in the base of the skull, brain, sinus, parapharyngeal space, carotid sheath region, wing and outside muscle, museulus long us capitis. (2) CT/MRI image fusion is helpful to improve the accuracy of Sketching. (3) MRI was superior to CT in radition plan.Sometimes the target is closed to the normal tissue, while meeting the target dose may lead to increased dose on normal organ.In order to protect normal organs,we make radiotherapy plan again. Abstract Objective:We compared the tumor volumes and tumor regression rate which delineated based on CT and on fusion image that combined CT and MRI image When the case of nasopharyngeal carcinoma were treated by Intensity Modulated Radiation Therapy(IMRT) on 5th week (about 50Gy).Methods:We collected 20 cases of nasopharyngeal carcinoma who were treated by IMRT on 5th week, patients underwent enhenced CT and MRI scans nasoPharynx again,two images transmitted to planning systems. Make image fusion on the use of the image fusion software on workstation,and use LandMark as the registration methods. Senior radiotherapy doctors respectively delineated the volumes in every layer on CT and CT/MRI image. We compared the tumor volumes and tumor regression rate which delineated the volumes that based on CT and on fusion image that combined CT and MRI image When the case of nasopharyngeal carcinoma were treated by Intensity Modulated Radiation Therapy(IMRT) on 5th week (about 50Gy). Result:The tumor volumes which delineated on CT and CT/MRI image is 39.07±11.15 cm3, 29.81±10.42 cm3, p＜0.05, there were Significant difference in early and advanced patients, we calculate the rate of tumor regression for the tumor volumes which were delineated basing on CT and CT/MRI, The results show that the tumor regression rate based on CT/MRI wasgreater than the tumor regression rate based on CT. We analysised the result betweentthe tumor volumes respectively under CTand CT/MRI. Conelusions:As the role of evaluating the tumor regression rate, CT/MRI image is superior to CT alone.