Ultrafast Perfusion-Weighted MRI of Functional Brain Activation in Rats During Forepaw Stimulation: Comparison withT*2-Weighted MRI

Abstract

A fast version of the arterial spin tagging technique for the detection of cerebral perfusion is presented. Based on adiabatic spin inversion in combination with snapshot FLASH imaging, our technique allows the recording of perfusion changes with a temporal resolution of about 3 s. Differences of cerebral perfusion dependent on the choice of anesthesia were observed in rat brain. Furthermore, with this arterial spin tagging method we demonstrated perfusion increases in the somatosensory cortex of anaesthetized rats during forepaw stimulation. Comparison of the activated areas in the T*2‐weighted BOLD images and the perfusion‐weighted images showed good spatial correspondence, but the sensitivity to the functional activation was more than ten times higher in the perfusion technique.

Time course of circulatory and metabolic recovery of cat brain after cardiac arrest assessed by perfusion- and diffusion-weighted imaging and MR-spectroscopy

“…The spin tagging method has been shown to be sensitive to fast perfusion changes in rat brain occuring after functional activation of cerebral cortex [8] or during hypercapnia [9]. In the present study, the feasibility of serial measurements of regional cerebral perfusion with arterial spin labeling was demonstrated in a feline model of prolonged CA and CPR.…”

“…PWI was performed using the ultrafast arterial spin tagging technique as previously described in detail [8]. The PWI sequence consisted of two similar image acquisition phases separated by a recovery period.…”

“…In the present study, perfusion-weighted imaging (PWI) was performed, for the first time, in a feline model of prolonged CA and cardiopulmonary resuscitation (CPR) by an ultrafast version of the arterial spin tagging method based on snapshot FLASH imaging. This method allows recording of fast cerebral perfusion changes in rats [8,9], and has not been employed before to describe the post-ischaemic CBF variations in experimental models of global cerebral ischaemia. Diffusionweighted imaging (DWI) was used to calculate the apparent diffusion coefficient of water (ADC).…”

The age-related deficit in LTP is associated with changes in perfusion and blood-brain barrier permeability

“…The ASL sequence consisted of a 5-second preparation interval containing the inversion pulse, followed by a snapshot fast low-angle shot (FLASH) image acquisition (echo time [TE] [Kerskens et al, 1996]). Flow-induced fast adiabatic passage of inflowing inverted arterial spins was performed using a rectangular pulse, inverting arterial spins that then travel to the imaging plane (Dixon et al, 1986;Kelly et al, 2009).…”

“…A fast T1-weighted fast low-angle shot sequence (TE ϭ 2.5 ms, TR ϭ 4.5 ms, FA ϭ 30°, BW ϭ 100 kHz, NR ϭ 60, slice thickness ϭ 1.5 mm, number of slices ϭ 11, FOV ϭ 3.0 ϫ 3.0 cm, matrix ϭ 128 ϫ 128, acquisition time ϭ 15 minutes [Kerskens et al, 1996]) with T2*-crusher gradients was developed to assess blood brain barrier permeability to the contrast agent meglumine gadopentate. The tail vein catheter was flushed with saline, and the cannula and tubing were loaded with the contrast agent.…”