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PT  - JOURNAL ARTICLE
AU  - Kim, H.S.
AU  - Kim, S.Y.
AU  - Kim, J.M.
TI  - Underestimation of Cerebral Perfusion on Flow-Sensitive Alternating Inversion Recovery Image: Semiquantitative Evaluation with Time-to-Peak Values
AID  - 10.3174/ajnr.A0720
DP  - 2007 Nov 01
TA  - American Journal of Neuroradiology
PG  - 2008--2013
VI  - 28
IP  - 10
4099  - http://www.ajnr.org/content/28/10/2008.short
4100  - http://www.ajnr.org/content/28/10/2008.full
SO  - Am. J. Neuroradiol.2007 Nov 01; 28
AB  - BACKGROUND AND PURPOSE: We assessed the underestimation of cerebral perfusion measured by the flow-sensitive alternating inversion recovery (FAIR) technique in patients with carotid stenosis and compared the technique with dynamic susceptibility contrast (DSC) MR images.MATERIALS AND METHODS: We studied 42 areas of decreased cerebral blood flow (CBF) using 3 FAIR images with different inversion times (TIs) in 42 consecutive patients with unilateral carotid stenosis of more than 50%. The width of decreased CBF area (wCBF) was qualitatively assessed. We analyzed the ratio of CBF (rCBF) and the time-to-peak (TTP) difference (dTTP) between the ipsilateral hemisphere to carotid stenosis and contralateral normal area using regions of interest (ROIs) at the same location.RESULTS: In the areas with more prolonged TTP (dTTP ≥3.2 s), the wCBF obtained from the FAIR images with TI of 1600 ms was smaller than those from the FAIR images with a TI of 800 ms and 1200 ms in all cases. The mean rCBF obtained from the FAIR images with a TI of 1200 ms was significantly lower than that obtained from the FAIR images with a TI of 1600 ms (P &amp;lt; .01) in the areas with more prolonged TTP. In the areas with less prolonged TTP (dTTP &amp;lt;3.2 s), the wCBF and mean rCBF were not significantly different between the 2 FAIR images (TI, 1200 and 1600 ms).CONCLUSION: If TTP is delayed significantly (dTTP ≥3.2 s), the FAIR with intermediate or short TI showed underestimation of perfusion in the same area with delay in TTP.