Differentiating Hemodynamic Compromise by the OEF Response to Acetazolamide in Occlusive Vascular Disease
- 1.4k Downloads
Identification of increased stroke risk in a population of symptomatic patients with occlusive vascular disease (OVD) is presently accomplished by measurement of oxygen extraction fraction (OEF) or cerebrovascular reserve (CVR). However, many regions identified by compromised CVR are not identified by OEF. Our aim was to determine whether the response of OEF to acetazolamide, namely, oxygen extraction fraction response (OEFR) would identify those hemispheres in hemodynamic compromise with normal OEF. Nine patients symptomatic with transient ischemic attacks and strokes, and with occlusive vascular disease were studied. Anatomical MRI scans and T2-weighted images were used to identify and grade subcortical white matter infarcts. PET cerebral blood flow (CBF) and OEF were measured after acetazolamide. The relationship between CVR and oxygen extraction fraction response (OEFR) showed that positive OEFR occurred after acetazolamide despite normal baseline OEF values. The two hemispheres with positive OEFR were also associated with severe (> 3 cm) subcortical white matter infarcts. We found that the OEFR was highly correlated with CVR and identified hemispheres that were hemodynamically compromised despite normal baseline OEF.
KeywordsPositron Emission Tomography Positron Emission Tomography Study Oxygen Extraction Fraction Hemodynamic Compromise Dynamic Positron Emission Tomography
Unable to display preview. Download preview PDF.
- 1.E. M. Nemoto, H. Yonas, H. Kuwabara, R. Pindzola, D. Sashin, C. C. Meltzer, J. C. Price, and Y. F. Change, Detection of stage II compromised cerebrovascular reserve by Xenon-CT cerebral blood flow with acetazolamide and oxygen extraction fraction by positron emission tomography, in: Brain Imaging Using PET, edited by M. Senda, Y. Kimura, and P. Herscovitch (Academic Press, New York, 2002), pp. 259–267.Google Scholar
- 3.S. Ohta, E. Meyer, H. Fujita, D. C. Reutens, A. Evans, and A. Gjedde, Cerebral [15O] water clearance in humans determined by PET: I. Theory and normal values, J. Cereb. Blood Flow Metab. 16, 765–780 (1966).Google Scholar
- 4.H. Iida, I. Kanno, S. Miura, M. Murakami, K. Takahashi, and K. Uemura, Error analysis of a quantitative cerebral blood flow measurement using H2 15O autoradiography and positron emission tomography with respect to the dispersion of the input function, J. Cereb. Blood Flow Metab. 6, 536–545 (1986).PubMedGoogle Scholar
- 5.M. A. Mintun, M. E. Raichle, W. R. Martin, and P. Herscovitch, Brain oxygen utilization measured with O-15 radiotracers and positron emission tomography, J. Nucl. Med. 25, 177–187 (1983).Google Scholar
- 7.E. M. Nemoto, H. Yonas, H. Kuwabara, R. R. Pindzola, D. Sashin, C. C. Meltzer, J. C. Price, Y. Chang, and D. W. Johnson, Identification of hemodynamic compromise by CVR and OEF in occlusive vascular disease, J. Cereb. Blood Flow Metab. (In press, October 2004).Google Scholar
- 8.I. Kanno, K. Uemura, S. Higano, M. Murakami, H. Iida, S. Miura, F. Shishido, A. Inugami, and I. Sayama, Oxygen extraction fraction at maximally vasodilated tissue in the ischemic brain estimated from the regional CO2 responsiveness measured by positron emission tomography, J. Cereb. Blood Flow Metab. 8(2), 227–235 (1988).PubMedGoogle Scholar
- 10.M. Imaizumi, K. Kitagawa, K. Hashikawa, N. Oku, T. Teratani, M. Takasawa, T. Yoshikawa, P. Rishu, T. Ohtsuki, M. Hori, M. Matsumoto, and T. Nishimura, Detection of misery perfusion with split-dose 123I-iodoamphetamine single-photon emission computed tomography in patients with carotid occlusive diseases, Stroke 33(9), 2217–2223 (2002).PubMedCrossRefGoogle Scholar