Journal of Medical Physics
 Home | Search | Ahead of print | Current Issue | Archives | Instructions | Subscription | Login  The official journal of AMPI, IOMP and AFOMP      
 Users online: 513  Home  EMail this page Print this page Decrease font size Default font size Increase font size 
TECHNICAL NOTE
Year : 2022  |  Volume : 47  |  Issue : 2  |  Page : 206-211

Significance of Dosimetric Parameters in Patients Undergoing Gamma Knife Radiosurgery for Vestibular Schwannoma


1 Department of Neurosurgery and Gamma Knife Radiosurgery, P.D. Hinduja Hospital and MRC, Mumbai, Maharashtra, India
2 Department of Radiation Oncology, P.D. Hinduja Hospital and MRC, Mumbai, Maharashtra, India

Correspondence Address:
Dr. Shobha Jayaprakash
Department of Neurosurgery and Gamma Knife Radiosurgery, P.D. Hinduja Hospital and MRC, Veer Savarkar Marg, Mahim, Mumbai - 400 016, Maharashtra
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jmp.jmp_5_22

Rights and Permissions

Vestibular schwannoma (VS) is a benign, encapsulated, and slow-growing tumor of the myelin-forming cells of the 8th cranial nerve. Gamma Knife radiosurgery (GKRS) has become a widely accepted primary treatment modality for small- to medium-sized VSs. In the case of VS, highly conformal, precisely focused radiation is delivered to the acoustic tumor in a single session under the direct supervision of a radiosurgery team. Aim: This study aims to determine the significance of Conformity Index and Gradient Index (GI) in patients undergoing GKRS for VS, retrospectively, and re-assess the plans. Materials and Methods: A dosimetric study of 112 patients of VS (both operated and nonoperated) treated on Gamma Knife Perfexion unit at our hospital, over a 3-year period, was carried out retrospectively. The patients' mean age at the time of GKRS was 48 years and the mean dose to the tumor margin was 13 Gy. The conformality of the treatment plan was determined by Conformity Index. GI determines fall off dose outside the target. Results: The dosimetric parameters such as Conformity Index and GI were calculated using the dose-volume histograms and the volume analysis tools available in the Leksell Gamma Plan using TMR 10 algorithm. The mean Paddick Conformity Index was found to be around 0.80 ± 0.085 and the mean GI was 2.67 ± 0.22. Conclusions: The dosimetric parameters can be used to evaluate the dose coverage and conformity and dose fall off outside the target.


[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
    Viewed58    
    Printed0    
    Emailed0    
    PDF Downloaded16    
    Comments [Add]    

Recommend this journal