Comparison of hyperpolarized (3)He MRI rat lung volume measurement with micro-computed tomography.
In this study, the upper-limit volume (gas plus partial tissue volume) as well as absolute volume (gas only) of lungs measured with hyperpolarized (3)He-MR imaging is compared with that determined by micro-computed tomography (CT) under similar ventilation conditions in normal rats. Five Brown Norway rats (210-259 g) were ventilated with O(2), alternately with (3)He, using a computer-controlled ventilator, and 3D density-weighted images of the lungs were acquired during a breath hold after six wash-in breaths of (3)He. The rats were then transferred to a micro-CT scanner, and a similar experimental setup was used to obtain images of the lungs during a breath hold of air with an airway pressure equal to that of the MR imaging breath hold. The upper-limit and absolute volumes obtained from (3)He-MR and micro-CT methods were not significantly different (p > 0.05). The good agreement between the lung volumes measured with the two imaging methods suggests that (3)He-MR imaging can be used for quantitative analysis of lung volume changes in longitudinal studies without the exposure to the ionizing radiation which accompanies micro-CT imaging.
Akhavan Sharif
M Reza
MR
Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, USA.
Lam
Wilfred W
WW
Ouriadov
Alexei V
AV
Holdsworth
David W
DW
Santyr
Giles E
GE
D000818:Animals; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008168:Lung / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D008176:Lung Volume Measurements / Q000295:instrumentation / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D051381:Rats; D055114:X-Ray Microtomography / Q000295:instrumentation / Q000379:methods*