Keywords:
Lung, Thorax, CT, CT-Quantitative, Image manipulation / Reconstruction, Computer Applications-Detection, diagnosis, Radiation therapy / Oncology, Radiation oncology in Developing Nations
Authors:
X. Hu1, X. Fang2, H. Chen3, C. Hu4; 1Wuxi, Ji/CN, 2wuxi city, ji/CN, 3Wuxi,Jiangsu/CN, 4Suzhou/CN
DOI:
10.1594/ecr2013/C-0021
Purpose
Radiation-induced lung injury (RILI) is one of the important common complications occurring during or after the thoracic radiotherapy,
and it is a major limiting factor for radiation therapy demanding increased awareness and early clinical recognition of this entity (1-3).
The acute RILI (ARILI) is defined by the US Radiation Therapy Oncology Group (RTOG) as RILI occurring within 90 days after commencement of radiotherapy(4).
Manifestations of ARILI on HRCT images are considered to be the most objective and reliable evidence for diagnosis of this entity(5-8).
However,
major challenges exist in using serial CT scanning for assessing pulmonary changes after radiation(7).
In most cases when ARILI is detected by HRCT,
the radiotherapy course is in its final stages or has been completed.
It is frequently too late to modify or readjust the therapeutic schedule,
and consequently irreversible changes in lung tissue are already present incurred.
It has been recently noted that morphological change usually occurs later than functional alteration or metabolic response in this entity(9,10).
Furthermore,
it is often difficult to predict the true extent of pneumonitis after completion of therapy in individual patients,
and this may limit reliability of CT in early diagnosis of ARILI for treatment planning(11).
Hence,
early detection of ARILI is instrumental for early intervention or therapy modification.
Our clinical research has found that functional imaging,
especially CT perfusion metrics such as pulmonary vascular permeability,
allow for earlier and more accurate RILI diagnosis.
To date,
there are no reports of early diagnosis of RILI using CT perfusion in the literature.
The purpose of this study is to evaluate the feasibility of early detection of ARILI with CT perfusion imaging (CTPI).