Technical NoteImproved selective visualization of internal and external carotid artery in 4D-MR angiography based on super-selective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK)
Introduction
Digital subtraction angiography (DSA) is the current standard diagnostic modality for neurovascular disease. It provides anatomical and flow dynamic information of vessels with high spatial and temporal resolution. However, this method carries risks of neurological complications, adverse reactions associated with contrast agents and radiation exposure [1].
As a non-invasive approach, arterial spin labeling (ASL) demonstrated the ability of non-contrast enhanced intracranial magnetic resonance angiography (MRA) with three dimensional (3D) spatial and dynamic acquisition (4D) in such neurovascular diseases as steno-occlusive disease, moyamoya disease, arteriovenous malformations (AVM) and dural arteriovenous fistula (dAVF) [[2], [3], [4], [5], [6], [7]].
Furthermore, there are reports of 4D-MRA techniques aimed at vessel-selective flow visualization, which is another clinically important feature of DSA [[8], [9], [10], [11]]. Understanding territorial flow of each vessel is important in determining the treatment strategy, such as identification of feeding arteries, detailed preoperative evaluations, and planning of interventional or surgical procedures. One vessel-selective 4D-MRA approach that has already been clinically validated is contrast inherent inflow-enhanced multi-phase angiography combined with vessel-selective arterial spin labeling technique (CINEMA-select) [9]. This approach has been shown to have clinical usefulness in the evaluation of intracranial AVMs by detecting the feeding arteries and in the estimation of detailed information about the nidus.
However, as a Look-Locker sampling strategy is used in CINEMA-select to acquire multiple time point data, signal saturation due to consecutive radiofrequency (RF) pulses can lead to insufficient vessel visualization, particularly at later time points. Moreover, CINEMA-select is limited in terms of vessel selectivity. For example, it is difficult for CINEMA-select to separately visualize territorial flow of the internal carotid artery (ICA) and the external carotid artery (ECA), as a spatially non-selective label pulse is used in the foot-to-head direction and the label slab typically includes the common carotid artery [9]. This could be clinically significant in understanding the vessel responsible for extracranial-intracranial bypass flow, the feeding artery, the nidus and the draining vein circulation in AVM or the shunt flow in dAVF.
Four dimensional (4D) MR angiography based on pseudo-continuous arterial spin labeling (pCASL) combined with CENTRA-keyhole and view-sharing, named 4D-PACK, has been proposed as a 4D-MRA technique [2,12]. With this technique, acquisition times were accelerated by using keyhole and view-sharing and better peripheral artery visualization with longer transit times compared to CINEMA was achieved [2,12]. However, this technique does not have vessel selectivity.
Recently, the super-selective technique, a pCASL-based technique, was introduced as a vessel-selective labeling technique [13]. In this study, we propose combining 4D-PACK with super-selective labelling, referred to as 4D-S-PACK (4D-MRA based on super-selective pCASL with CENTRA-keyhole) hereafter. The aim of this study is to investigate 4D-S-PACK label selectivity for ICA and ECA, as well as its capability to visualize individual territorial flow, especially focusing on peripheral flow in patients with delayed or long-transit time flow circulation.
Section snippets
4D-S-PACK
The 4D-S-PACK scheme is visualized in Fig. 1. The concept and scheme of 4D-S-PACK is the same as of 4D-PACK except that the super-selective pulse is used in the pCASL module in the case of 4D-S-PACK [12,13]. In addition to the non-selective pCASL that uses gradient Gz in the direction of the blood flow, gradients perpendicular to the flow direction (Gx, Gy) are added in 4D-S-PACK (Fig. 1a). By dynamically changing the direction of the additional gradients, a circular or elliptical label spot
Results
Representative 4D-MRA images in the right ICA circulation generated from 4D-S-PACK and CINEMA-select are shown in coronal and axial orientations in Fig. 3. The images obtained by 4D-S-PACK exhibited high-flow visualization in peripheral areas (yellow arrows) for MCA. The ICA circulation was visualized without visualization of ECA territorial flow in 4D-S-PACK; ECA territorial flow was visualized in CINEMA-select (blue arrows), as it utilizes common carotid artery labels.
Representative right ECA
Discussion
In this study, we propose a new vessel-selective 4D-MRA approach called 4D-S-PACK, a 4D-MRA technique with super-selective combined pCASL, accelerated using keyhole and view-sharing techniques.
In the examination of the healthy volunteers, 4D-S-PACK showed better artery visualization in the MCA and STA peripheral regions compared to CINEMA-select. In a previous study comparing 4D-PACK and CINEMA, similar results were reported [12]. Though there is a difference between vessel-selective and
Acknowledgements
We thank Tetsuo Ogino, Yuta Akamine and Yu Ueda for valuable help with the imaging sequence development or for giving advice about study design.
References (16)
- et al.
A novel application of four-dimensional magnetic resonance angiography using an arterial spin labeling technique for noninvasive diagnosis of Moyamoya disease
Clin Neurol Neurosurg
(2015) - et al.
Collateral circulation via the circle of Willis in patients with carotid artery steno-occlusive disease: evaluation on 3-T 4D MRA using arterial spin labelling
Clin Radiol
(2015) - et al.
3D time-resolved vessel-selective angiography based on pseudo-continuous arterial spin labeling
Magn Reson Imaging
(2015) - et al.
Complications of diagnostic cerebral angiography: evaluation of 19,826 consecutive patients
Radiology
(2007) - et al.
4D ASL-based MR angiography for visualization of distal arteries and leptomeningeal collateral vessels in moyamoya disease: a comparison of techniques
Eur Radiol
(2018) - et al.
Non-gadolinium dynamic angiography of the neurovasculature using arterial spin labeling MRI: preliminary experience in children
MAGMA
(2017) - et al.
Evaluation of intracranial arteriovenous malformations with four-dimensional arterial-spin labeling-based 3-T magnetic resonance angiography
J Comput Assist Tomogr
(2016) - et al.
Intracranial dural arteriovenous fistulas: evaluation with 3-T four-dimensional MR angiography using arterial spin labeling
Radiology
(2014)
Cited by (5)
Optimization of 4D-MR angiography based on superselective pseudo-continuous arterial spin labeling combined with CENTRA-keyhole and view-sharing (4D-S-PACK) for vessel-selective visualization of the internal carotid artery and vertebrobasilar artery systems
2022, Magnetic Resonance ImagingCitation Excerpt :This study was approved by the Institutional Review Board of Kyushu University Hospital (No. 20192029), and written informed consent was obtained from all subjects. [R2.1]: This study used a new approach for vessel-selective 4D-MRA as identical superselective sequence and 4D-S-PACK scheme reported by Obara et al. [18]. In 4D-S-PACK, superselective 4D-MRA images are acquired by dynamically changing the labeling duration and, after the application of a control or label pulse, implementing a shot post-labeling delay (PLD) and then acquiring images using RF and gradient-spoiled T1-enhanced turbo field echo (T1-TFE) acquisition.
Arterial Spin Labeling-Based MR Angiography for Cerebrovascular Diseases: Principles and Clinical Applications
2023, Journal of Magnetic Resonance ImagingVessel-Selective 4D-MRA Using Superselective Pseudocontinuous Arterial Spin-Labeling with Keyhole and View-Sharing for Visualizing Intracranial Dural AVFs
2022, American Journal of Neuroradiology