Journal of Medical Physics
 Home | Search | Ahead of print | Current Issue | Archives | Instructions | Subscription | Login  The official journal of Association of Medical Physicists of India      
 Users online: 64  Home  EMail this page Print this page Decrease font size Default font size Increase font size 
ORIGINAL ARTICLE
Year : 2014  |  Volume : 39  |  Issue : 3  |  Page : 150-155

A dosimetric evaluation of flattening filter-free volumetric modulated arc therapy in nasopharyngeal carcinoma


Department of Radiotherapy, Cancer Hospital and Institution, Chinese Academy of Medical Sciences, Panjiayuan NaiLi 17#, Chaoyang Dist, Beijing, China

Correspondence Address:
Jianrong Dai
Department of Radiotherapy, Cancer Hospital and Institution, Chinese Academy of Medical Sciences, Panjiayuan NaiLi 17#, Chaoyang Dist, Beijing
China
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0971-6203.139003

Rights and Permissions

Purpose: To explore the dosimetric effects of flattening filter-free (FFF) beams in volumetric modulated arc therapy (VMAT) of nasopharyngeal carcinoma via a retrospective planning study. Materials and Methods: A linear accelerator (LINAC) was prepared to operate in FFF mode and the beam data were collected and used to build a model in TPS. For 10 nasopharyngeal carcinoma (NPC) cases, VMAT plans of FFF beams and normal flattened (FF) beams were designed. Differences of plan quality and delivery efficiency between FFF-VMAT plans and filter filtered VMAT (FF-VMAT) plans were analyzed using two-tailed paired t-tests. Results: Removal of the flattening filter increased the dose rate. Averaged beam on time (BOT) of FFF-VMAT plans was decreased by 24.2%. Differences of target dose coverage between plans with flattened and unflattened beams were statistically insignificant. For dose to normal organs, up to 4.9% decrease in V35 of parotid grand and 4.5% decrease in averaged normal tissue (NT) dose was observed. Conclusions: The TPS used in our study was able to handle FFF beams. The FFF beam prone to improve the normal tissue sparing while achieving similar target dose distribution. Decreasing of BOT in NPC cases was valuable in terms of patient's comfort.


[FULL TEXT] [PDF]*
Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)
 

 Article Access Statistics
    Viewed1895    
    Printed72    
    Emailed0    
    PDF Downloaded118    
    Comments [Add]    

Recommend this journal