Brain perfusion measured by flow-sensitive alternating inversion recovery (FAIR) and dynamic susceptibility contrast-enhanced magnetic resonance imaging: comparison with nuclear medicine technique

Abstract

The aim of this study was to compare cerebral perfusion images and regional cerebral blood flow (rCBF) of SPECT study with the images and regional intensity of relative cerebral blood flow (CBF) images acquired by contrast-enhanced perfusion MR imaging (pMRI) and flow-sensitive alternating inversion recovery (FAIR). Twelve patients with various cerebral diseases were underwent I-123-IMP SPECT, pMRI, and FAIR studies to measure rCBF. A total of 12 regions of interest (ROI) were created over cerebrum and cerebellum to acquire the corresponding rCBF from I-123-IMP study and regional average signal intensity from CBF images of pMRI and FAIR studies. Left-to-right (L/R) and cerebral-to-cerebellar (CCR) ratios were created from the rCBF of I-123-IMP and signal intensity of CBF images of pMRI and FAIR. Image quality of FAIR was the poorest among all; however, CBF images of pMRI and FAIR images show comparatively decreased intensity at the corresponding site of decreased perfusion on I-123-IMP images. Both FAIR and pMRI images showed high intensity along the sinuses, choroid plexus, and large vessels in sulci. No significant correlation was found among all imaging modalities. But L/R ratio of I-123-IMP showed significant correlation with those of pMRI and FAIR, but for CCR, significant correlation was observed only between I-123-IMP and FAIR. Perfusion images of both pMRI and FAIR may produce images comparable to SPECT study. But to calculate absolute CBF more easy-to-apply and accurate algorithms are needed to overcome the artifacts from large vessels.

Perfusion MRI of brain tumours: a comparative study of pseudo-continuous arterial spin labelling and dynamic susceptibility contrast imaging

“…Some DSC-MRI, positron emission tomography (PET), and single photon emission computed tomography studies have used the cerebellum as a reference region when analysing perfusion and tracer uptake in brain tumours [29, 30], but normalisation of TBF to contralateral GM and in particular contralateral WM has most often been performed in MRI studies[6, 7, 26, 31–33]. However, because cerebellar perfusion usually is unaffected by pathology in the brain and is higher than WM CBF (Table 3) and thereby is easier to measure with the ASL technique, we have consequently chosen to focus on the normalisation to cerebellum in this study.…”

Underestimation of Cerebral Perfusion on Flow-Sensitive Alternating Inversion Recovery Image: Semiquantitative Evaluation with Time-to-Peak Values

“…This MR perfusion technique has been validated in several experimental studies [17][18][19] and has been used to examine patients with ischemic cerebrovascular disease. [20][21] Compared with continuous ASL (CASL), which uses relatively long width radio-frequency (RF) pulses, PASL techniques use nearly instant pulses with comparatively low levels of RF deposition for spin labeling and are particularly advantageous in circumstances in which the specific absorption rate (SAR) imposes a limitation, such as a high magnetic field and pediatric imaging. 22 However, the short half-life of spin-labeled arterial water can complicate the quantification of perfusion on PASL.…”

“…Arbab et al 21 reported a correlation between the singlesection FAIR perfusion images and contrast-enhanced dynamic perfusion MR images and found a good correlation between FAIR and relative CBF. In our study, we used the TTP method to quantify the blood flow transit delay and to assess errors in CBF measurement from PASL imaging.…”

Operator-bias-free Comparison of Quantitative Perfusion Maps Acquired with Pulsed-continuous Arterial Spin Labeling and Single-photon-emission Computed Tomography

“…Most studies comparing ASL and other brain perfusion methods have set ROIs manually on the CBF map, 12,[16][17][18] but the manual setting of ROIs introduces inter-rater variability, which is avoided using 3DSRT because the software automatically draws the segmented ROI after registration to an anatomically standardized brain image. In our study, use of 3DSRT allowed detailed comparison in each region of the brain.…”

“…Good agreement has been reported between ASL and nuclear medicine studies. 12,[16][17][18] However, these studies have usually involved the manual setting of regions of interest (ROI) on the CBF map, introducing inter-rater variability and making detailed comparisons of brain regions difficult.…”