[Diagnostic methods for the quantification of radiation injuries of the lungs].
OBJECTIVE
The aim of this paper is to find techniques for quantifying radiation lung injury after irradiation with lung involvement to improve an early diagnosis.


METHODS
The case of a patient with NSCLC was used to demonstrate different methods in order to quantify a developing pneumopathy after radiation treatment. By means of HRCT studies in the follow-up, a procedure was developed by defining a test-ROI in high-dose areas of the lung and evaluating the corresponding HU-histogramm for the parameters of the lung peak. Changes during the follow-up can be derived from the differential HU-histogram by the determination of a parameter called delta HUrel, which quantifies the shift to higher HU values. Alternatively, a Fourier analysis of the lung pattern within the test-ROI results in a Fourier amplitude distribution, which reacts sensitively to changes during the follow-up. Furthermore, a Fourier-frequency histogram can be derived which is independent of the spatial orientation of the density pattern.


RESULTS
From the HRCT follow-up study, values for delta HUrel can be derived to be 0.24, 0.44, and 0.50 (56, 100 and 422 days after beginning the treatment). The differential Fourier frequency-histogram presentations demonstrate pronounced pattern changes.


CONCLUSIONS
The presented methods demonstrate possibilities to quantify radiation lung injury. The proven sensitivity can possibly be improved after the introduction of a breath triggered HRCT technique.
Bogner
L
L
Klinik und Poliklinik für Strahlentherapie und Radioonkologie, Universität Regensburg. ludwig.bogner@klinik.uni-regensburg.de
Schiessl
I
I
Spiegler
W
W
Meyer
B
B
Herbst
M
M
D002289:Carcinoma, Non-Small-Cell Lung / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008168:Lung / Q000000981:diagnostic imaging / Q000528:radiation effects*; D008175:Lung Neoplasms / Q000532:radiotherapy*; D011832:Radiation Injuries / Q000000981:diagnostic imaging* / Q000209:etiology; D011878:Radiotherapy / Q000009:adverse effects*; D011879:Radiotherapy Dosage; D014057:Tomography, X-Ray Computed
Diagnostische Methoden zur Erkennung radiogener Spätschäden der Lunge.