3D Fluid-Attenuated Inversion Recovery Imaging: Reduced CSF Artifacts and Enhanced Sensitivity and Specificity for Subarachnoid Hemorrhage

Abstract

BACKGROUND AND PURPOSE: FLAIR images are highly sensitive for SAH. However, CSF flow artifacts caused by conventional FLAIR can produce false-positive results. Here, we compare 3D and 3D FLAIR sequences, focusing on their potential for containing these artifacts and their sensitivity and specificity for detection of SAHs.

Comparison of 3D Cube FLAIR with 2D FLAIR for Multiple Sclerosis Imaging at 3 Tesla

“…These findings are confirmed by our measurements, which showed higher values for all calculated ratios except for the CNR lesion GM. Another reason for the improved lesion detection with Cube FLAIR could be the superior CSF suppression and absence of CSF flow artifacts, which has been demonstrated before [12]. This is because no inflow of unsuppressed CSF from outside the imaging volume can occur due to the large volume excited using 3 D techniques.…”

“…Cube has already been evaluated for imaging of the knee and ankle, yielding positive results [10,11]. Moreover, Cube FLAIR was shown to produce almost no CSF flow artifacts when applied in brain imaging [12]. We sought to test the Cube FLAIR sequence for parenchymal brain imaging in the field of multiple sclerosis at 3 Tesla.…”

The Technical and Clinical Features of 3D-FLAIR in Neuroimaging

“…9). 9 Lack of visualization for intra-arterial signal in the patients with acute ischemic stroke in 3D-FLAIR is one of the drawbacks. 13 Cortical microinfarcts (CMIs) are detected as small foci restricted to the cerebral cortex in autopsy brains.…”

“…18 High sensitivity to subtle T 1 changes in fluid FLAIR is reported to be more sensitive to subtle T 1 changes in fluid than conventional T 1 -weighted images. [21][22][23][24][25][26][27][28][29][30] A FLAIR image allows the detection of subtle subarachnoid hemorrhage in the CSF space, 9 signal increases in CSF after the inhalation of oxygen, 31 and subtle compositional changes of the labyrinthine fluid (Figs. 6 and 7), 26,27,30,[32][33][34] which can be difficult to recognize on T 1 -weighted images.…”

Double Inversion Recovery MR Sequence for the Detection of Subacute Subarachnoid Hemorrhage

“…3D FLAIR is even more specific than 2D FLAIR by reducing flow-related artifacts, which are known to provide falsepositive findings on 2D FLAIR. 11 Nevertheless, SAH can still be misdiagnosed by using FLAIR imaging due to the time interval after onset 12 or artifacts. 13,14 T2* gradient-echo sequences are useful for subacute or chronic SAH depiction.…”