Comparison between acetazolamide challenge and 10% carbon dioxide challenge perfusion CT in rat C6 glioma.
OBJECTIVE
The aim of this study was to investigate the effect of perfusion computed tomography (PCT) with acetazolamide (ACZ) challenge and compare it to 10% carbon dioxide (CO(2)) challenge in rat C6 glioma.


METHODS
PCT was performed on 32 rats, including 20 with orthotopically implanted C6 gliomas and 12 serving as controls. Ten rats with gliomas and six normal rats underwent PCT with ACZ challenge. The other 10 rats with gliomas and six normal rats underwent PCT with 10% CO(2) challenge. The raw data were processed using Philips computed tomographic brain perfusion software. Perfusion parameters before and after the challenge were recorded. Percentage changes due to ACZ administration and 10% CO(2) challenge were calculated. Pearson's correlation coefficients were used to investigate relationships between percentage changes in perfusion parameters and vascular endothelial growth factor and microvessel density.


RESULTS
In C6 gliomas, percentage change in cerebral blood flow was significantly different between ACZ (72.73%) and 10% CO(2) (28.47%) challenge (P < .01). Percentage change in cerebral blood volume was 37.85% with ACZ and 24.69% with 10% CO(2) challenge (P = .02). In controls, percentage change in cerebral blood flow was significantly different between ACZ (117.42%) and 10% CO(2) (65.86%) challenge (P < .01). For percentage change in cerebral blood volume, there was no significant difference between ACZ (107.51%) and 10% CO(2) (92.95%) challenge. Significant correlations were observed among percentage changes in vascular endothelial growth factor, microvessel density, and cerebral blood volume (P < .01). Percentage change in cerebral blood flow correlated well with vascular endothelial growth factor.


CONCLUSIONS
The results of this study indicate that PCT with ACZ challenge is a more reliable technique compared to 10% CO(2) challenge for the quantitative evaluation of microcirculation in gliomas.
Department of Radiology, Huashan Hospital, Fudan University, Shanghai, China.
Na
N
Lu
Yue
Y
Di
Xiao-Yuan
XY
Feng
Jin-Wei
JW
Qiang
Jia-Wen
JW
Zhang
Yong-Gang
YG
Wang
Qi-Yong
QY
Guo
D000086:Acetazolamide / Q000494:pharmacology*; D000818:Animals; D001783:Blood Flow Velocity; D001932:Brain Neoplasms / Q000000981:diagnostic imaging*; D002245:Carbon Dioxide / Q000494:pharmacology*; D045744:Cell Line, Tumor / Q000637:transplantation; D002560:Cerebrovascular Circulation; D005910:Glioma / Q000000981:diagnostic imaging*; D008297:Male; D008833:Microcirculation; D009368:Neoplasm Transplantation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014057:Tomography, X-Ray Computed / Q000379:methods*
D002245:Carbon Dioxide; D000086:Acetazolamide