Evaluating the Effect of Arterial Pulsation on Cerebrospinal Fluid Motion in the Sylvian Fissure of Patients with Middle Cerebral Artery Occlusion Using Low b-value Diffusion-weighted Imaging

Abstract

Purpose Decrease in signal of the cerebrospinal fluid (CSF) on low b-value diffusion weighted image (DWI) due to non-uniform flow can provide additional information regarding CSF motion. The purpose of the current study was to evaluate whether arterial pulsations constitute the driving force of CSF motion. Methods We evaluated the CSF signals within the Sylvian fissure on low b-value DWI in 19 patients with unilateral middle cerebral artery (MCA) occlusion. DWI with b-value of 500 s/mm 2 was evaluated for a decrease in CSF signal within the Sylvian fissure including the Sylvian vallecula and lower, middle, and higher Sylvian fissures and graded as follows: the same as contralateral side; smaller signal decrease than that on contralateral side; and no signal decrease. MR angiography (MRA) findings of MCA were graded as follows: the same as contralateral, lower signal than contralateral signal, and no signal. In 15 patients, regional cerebral blood flow (rCBF) was evaluated using single-photon emission computed tomography (SPECT) studies and graded as > 90%, 90%–70%, and < 70% rCBF compared to contralateral. The correlations between the gradings were evaluated using G likelihood-ratio test. Results There was no statistically significant correlation between the MRA and low b-value DWI gradings of CSF in all areas. There were statistically significant correlations between the decreases in CBF on SPECT and CSF signals in the middle Sylvian fissure. Conclusion The driving force of CSF pulsation in the Sylvian sinus may be related to the pulsations of the cerebral hemisphere rather than direct arterial pulsations.

Cerebrovascular Responses in a Patient with Lundberg B Waves Following Subarachnoid Haemorrhage Assessed with a Novel Non-Invasive Brain Pulse Monitor: A Case Report

“…47,48 Other potential factors include sub-arachnoid blood overlying the lobes and dynamic movement of CSF over the lobes in response to cerebral blood flow and respiration. 49,50 Other NIRS technologies, such as the NIRO 200, found similar slow oscillations in phase with Lundberg B waves. However, the direction of change was the same for both hemispheres.…”

Diffusion Tensor Image Analysis ALong the Perivascular Space (DTI-ALPS): Revisiting the Meaning and Significance of the Method

“…138 Subsequently, reports have been published on the evaluation of CSF dynamics using multiple b-values, as well as reports evaluating the relationship between CSF pulsation and arterial pulse rate, and more detailed evaluation of spinal fluid pulsation with the addition of tensor information. [139][140][141] Assessment by measuring flow in the SAS along the middle cerebral artery by ultra-long echo time and low-b diffusion tensor imaging (DTIlow-b) has also been attempted; DTIlow-b has been proposed to reflect flow characteristics in one of the major CSF inflow pathways to the brain parenchyma (Fig. 5).…”

Clinical magnetic resonance imaging evaluation of glymphatic function

“…Some studies have correlated the diffusion coefficient measured by low b-value DWI to the velocity of the spins bulk flow. 71,[100][101][102][103][104][105][106][107][108][109][110] A low b-value diffusion gradient (5-150 s/mm 2 ) can be used to assess bulk flow velocities, 71,100,111 perfusion imaging, 112 and functional MRI. 101 Apparent diffusion coefficient (ADC) measurements using low b-values (short diffusion time) show restricted diffusion of CSF in choroid plexus cysts.…”

“…Low b-value DWI measurements of the Sylvian sinus reveal that the driving force behind CSF flow pulsation is independent of direct artery pulsations and may be connected to cerebral hemisphere pulsations. 105 A comprehensive animal investigation 106 demonstrated that the directional CSF flow has a distinct effect on diffusion signals by examining the influence of CSF flow on the diffusion signals at low b values of the ventricle in live and sacrificed rat brains. Additionally, it was demonstrated that the ADC may be used to evaluate both the pathological condition of the brain and the flow of CSF.…”