Emphysema quantification in inflation-fixed lungs using low-dose computed tomography and 3He magnetic resonance imaging.
OBJECTIVE
To evaluate the use of inflation-fixed lung tissue for emphysema quantification with computed tomography (CT) and He magnetic resonance (MR) diffusion imaging.


METHODS
Fourteen subjects representing a range of chronic obstructive pulmonary disease severity who underwent complete or lobar lung resection were studied. Computed tomographic measurements of lung attenuation and MR measurements of the hyperpolarized 3He apparent diffusion coefficient (ADC) in resected specimens fixed in inflation with heated formalin vapor were compared with measurements obtained before fixation.


RESULTS
The mean (SD) CT emphysema indices were 56% (17%) before and 58% (19%) after fixation (P = 0.77; R = 0.76). Index differences correlated with differences in lung volume (R = 0.47). The mean (SD) 3He ADCs were 0.40 (0.15) cm/s before and 0.39 (0.14) cm/s after fixation (P = 0.03, R = 0.98). The CT emphysema index and the 3He ADC were correlated before (R = 0.89) and after fixation (R = 0.79).


CONCLUSIONS
Concordance of CT and 3He MR imaging measurements in unfixed and inflation-fixed lungs supports the use of inflation-fixed lungs for quantitative imaging studies in emphysema.
Gierada
David S
DS
Mallinckrodt Institute of Radiology, Washington University, St Louis, MO 63105, USA. gieradad@wustl.edu
Woods
Jason C
JC
Jacob
Richard E
RE
Bierhals
Andrew J
AJ
Choong
Cliff K
CK
Bartel
Seth T
ST
Chang
Yulin V
YV
Das
Nitin A
NA
Hong
Cheng
C
Lutey
Barbara A
BA
Ritter
Jon H
JH
Pilgram
Thomas K
TK
Cooper
Joel D
JD
Patterson
G Alexander
GA
Battafarano
Richard J
RJ
Meyers
Bryan F
BF
Yablonskiy
Dmitriy A
DA
Conradi
Mark S
MS
D000368:Aged; D004646:Emphysema / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D005260:Female; D006371:Helium; D006801:Humans; D066298:In Vitro Techniques; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011013:Pneumonectomy; D011829:Radiation Dosage; D014057:Tomography, X-Ray Computed / Q000379:methods*
D006371:Helium