Hemodynamic parameter assessment with dynamic susceptibility contrast magnetic resonance imaging in unilateral symptomatic internal carotid artery occlusion.

BACKGROUND AND PURPOSE: Hemodynamic parameters such as regional cerebral blood volume (rCBV), mean transit time (MTT), and regional cerebral blood flow (rCBF) can be assessed by dynamic susceptibility contrast MRI. The aim of the present study was to apply this method in patients who had symptomatic unilateral internal carotid artery occlusion.

METHODS: Relative hemodynamic parameters (rCBV, MTT, and rCBF) were evaluated on the occluded side and thus compared with contralateral hemispheric values. We also attempted to detect any relationship between collateral flow and the hemodynamic parameters.

RESULTS: Although rCBV was clearly increased in five patients over the whole hemisphere, we did not observe a statistically significant difference regarding the whole sample between sides (mean rCBV, 14.1 +/- 4.58 on the occluded side versus 11.8 +/- 2.99 on the contralateral side, P>.10). MTT was clearly increased on the occluded side (mean MTT, 4.29 +/- 0.83 on the lesion side versus 3.14 +/- 0.81 on the contralateral side, P<.010). A statistically significant decrease of rCBF on the occluded side was observed (mean rCBF, 3.27 +/- 0.73 versus 3.93 +/- 1.03 on the contralateral side; P<.01).

CONCLUSIONS: A significant hemodynamic compromise in patients who had unilateral symptomatic carotid occlusion was observed according to CBF and MTT values. This approach might be promising in the understanding of cerebral hemodynamics in patients with vascular disorders.