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RT Journal Article
SR Electronic
T1 Correlative Assessment of Hemodynamic Parameters Obtained with T2<sup>*</sup>-weighted Perfusion MR Imaging and SPECT in Symptomatic Carotid Artery Occlusion
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1450
OP 1456
VO 21
IS 8
A1 Hyoung Kim, Jae
A1 Joo Lee, Sun
A1 Shin, Taemin
A1 Hun Kang, Kyeong
A1 Youb Choi, Pil
A1 Hee Kim, Jung
A1 Chul Gong, Jae
A1 Choi, Nack-Cheon
A1 Hoon Lim, Byeong
YR 2000
UL http://www.ajnr.org/content/21/8/1450.abstract
AB BACKGROUND AND PURPOSE: Perfusion MR imaging and single-photon emission CT (SPECT) are commonly used to evaluate hemodynamic status in patients with symptomatic occlusive cerebrovascular disease. These techniques rely on different underlying physiological mechanisms, and the data may not correspond. We studied the relationship between hemodynamic parameters obtained with these two methods.METHODS: We performed perfusion MR imaging and SPECT in 10 patients with symptomatic unilateral internal carotid artery occlusion. Relative cerebral blood volume (rCBV) and uncorrected mean transit time (uMTT) were obtained with dynamic contrast-enhanced T2*-weighted MR imaging. Relative cerebral blood flow (rCBF) and vascular reserve capacity were measured with 99mTc-HMPAO SPECT; vascular reserve capacity was calculated by the difference in CBF before and after acetazolamide challenge. Ratios of these hemodynamic parameters between the affected and contralateral vascular territories were calculated and compared.RESULTS: Normal-to-increased CBV, prolonged uMTT, decreased CBF, and normal-to-diminished vascular reserve capacity were observed in the affected vascular territories. Reduction of vascular reserve capacity corresponded well with uMTT but not with CBF and CBV. CBF, CBV, and uMTT did not correspond to one another.CONCLUSION: uMTT is more sensitive than the other parameters in estimating vascular reserve capacity. The relationship between parameters obtained with perfusion MR imaging and SPECT should be considered in assessing the hemodynamic status of patients with symptomatic occlusive cerebrovascular disease.