A new approach to quantifying lung damage after stereotactic body radiation therapy

Authors: Palma, David A.; van Söörnsen de Koste, John R.; Verbakel, Wilko F. A. R.; Senan, Suresh

Source: Acta Oncologica, Volume 50, Number 4, May 2011 , pp. 509-517(9)

Publisher: Informa Healthcare

Buy & download fulltext article:


Price: $55.00 plus tax (Refund Policy)



Radiological pneumonitis and fibrosis are common after stereotactic body radiotherapy (SBRT) but current scoring systems are qualitative and subjective. We evaluated the use of CT density measurements and a deformable registration tool to quantitatively measure lung changes post-SBRT. Material and methods. Four-dimensional CT datasets from 25 patients were imported into an image analysis program. Deformable registration was done using a B-spline algorithm (VelocityAI) and evaluated by landmark matching. The effects of respiration, contrast, and CT scanner on density measurements were evaluated. The relationship between density and clinician-scored radiological pneumonitis was assessed. Results. Deformable registration resulted in more accurate image matching than rigid registration. CT lung density was maximal at end-expiration, and most deformation with breathing occurred in the lower thorax. Use of contrast increased mean lung density by 18 HU (range 16––20 HU; p == 0.004). Diagnostic scans had a lower mean lung density than planning scans (mean difference 57 HU in lung contralateral to tumor; p == 0.048). Post-treatment CT density measurements correlated strongly with clinician-scored radiological pneumonitis (r == 0.75; p < 0.001). Conclusions. Quantitative analysis of changes in lung density correlated strongly with physician-assigned radiologic pneumonitis scores. Deformable registration and CT density measurements permit objective assessment of treatment toxicity.

Document Type: Research Article

DOI: http://dx.doi.org/10.3109/0284186X.2010.541934

Affiliations: Department of Radiation Oncology, VU University Medical Center, Amsterdam, The Netherlands

Publication date: May 1, 2011

More about this publication?
Related content


Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content

Text size:

A | A | A | A
Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages. print icon Print this page