Computed tomography monitoring of radiation-induced lung fibrosis in mice.
OBJECTIVE
To identify characteristics of lung fibrosis in a mouse model after radiotherapy (RT) using thin-section computed tomography (CT), histology and clinical parameters.


METHODS
Using a multislice CT-scanner, follow-up chest CT scans of 10 out of 72 included mice (C57BL/6J, 36 control mice, 36 mice (20Gy)) were performed every 2 weeks until week 26 after RT. Hounsfield units (HU) and cardiothoracic ratio (CTR) were measured, and a multireader analysis on characteristic lung changes was performed and correlated with histology and clinical parameters.


RESULTS
From weeks 4 to 8 after RT changes in histology (leukocyte count, extraalveolar edema, P < 0.01) and from week 12 changes in CT were detected (increase in HU, intralobular opacity and fibrotic strandings, P < 0.05). From week 14 clinical manifestations occurred (loss of weight, mobility, breathing, increased mortality, P < 0.01). CTR showed no significant changes. Three readers showed excellent interobserver agreement (kappa >0.84).


CONCLUSIONS
Thin-section CT in a mouse model is capable of detecting the development of lung fibrosis after RT prior to the onset of clinical deterioration.
Plathow
Christian
C
Department of Radiology, Deutsches Krebsforschungszentrum Heidelberg, Germany. c.plathow@dkfz.de
Li
Minglun
M
Gong
Ping
P
Zieher
Heike
H
Kiessling
Fabian
F
Peschke
Peter
P
Kauczor
Hans-Ulrich
HU
Abdollahi
Amir
A
Huber
Peter E
PE
D000818:Animals; D004487:Edema; D005260:Female; D006652:Histological Techniques; D007958:Leukocyte Count; D051379:Mice; D008810:Mice, Inbred C57BL; D023421:Models, Animal; D008991:Monitoring, Physiologic; D011658:Pulmonary Fibrosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D011833:Radiation Injuries, Experimental / Q000503:physiopathology*; D013909:Thorax / Q000528:radiation effects; D014057:Tomography, X-Ray Computed