# Quantitative ASL MR angiography and perfusion imaging for cerebral revascularization

> **NIH NIH R01** · UNIVERSITY OF SOUTHERN CALIFORNIA · 2022 · $1

## Abstract

PROJECT SUMMARY/ABSTRACT
Cerebrovascular disease is one of the leading causes of death and disability worldwide. Cerebral
revascularization, especially surgical revascularization, has evolved as an effective surgical therapy for the
management of chronic cerebrovascular diseases such as moyamoya disease, complex aneurysms, and
selected carotid steno-occlusive disease to improve the cerebral hemodynamics and reduce the risk of stroke.
Nonetheless, optimal surgical planning is still unclear as a variety of revascularization techniques can be
considered. To date, the choice of revascularization strategy is primarily based on the subjective interpretation
of flow demands in the at-risk territory. This results in a variable, subjective clinical practice that places patients
at risk for hemodynamics-related postoperative complications, significantly impacting the clinical outcomes. A
segmented and quantitative characterization of cerebral hemodynamics pre- and post-revascularization is
necessary to objectify flow requirements, standardize and improve patient care. However, none of the existing
clinical imaging modalities are able to provide high spatiotemporal resolution angiographic images with
quantitative hemodynamic information from individual arterial segments without contrast agents. Arterial spin
labeling (ASL) possesses appealing features that allow for the assessment of both perfusion and angiography
quantitatively. Building upon our successful track record on the development of ASL 4D MRA as well as ASL
perfusion imaging, the goal of the present project is to develop and evaluate an easily-carry-out noninvasive ASL
suite consisting of advanced 4D MRA and perfusion territorial mapping to quantitively assess cerebral
hemodynamics from individual arteries and downstream tissue pre and post-cerebral revascularization. In Aim
1, we will develop and optimize a novel rapid high spatiotemporal resolution 4D MRA technique (<5minutes). In
Aim2, we will develop and validate post-processing algorithms for cerebral hemodynamic quantification and
vascular territories with 4D MRA and random vessel-encoded ASL. By leveraging the rich clinical resource from
the USC Revascularization Center, in Aim 3, we will quantitively evaluate perioperative hemodynamics on
patients who undergo cerebral revascularization and study the association of revascularization-related
hemodynamic change with clinical outcomes. The successful completion of this project will lead to a robust,
noninvasive, flexible, and quantitative ASL MRI suite within 10 min scan time that is ready to be incorporated
into clinical MRI settings. The proposed technique can be highly valuable as a potential imaging tool for the
quantitative evaluation of flow demands in cerebral revascularization.

## Key facts

- **NIH application ID:** 10401955
- **Project number:** 5R01NS118019-03
- **Recipient organization:** UNIVERSITY OF SOUTHERN CALIFORNIA
- **Principal Investigator:** Lirong Yan
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $1
- **Award type:** 5
- **Project period:** 2020-07-15 → 2022-05-02

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10401955

## Citation

> US National Institutes of Health, RePORTER application 10401955, Quantitative ASL MR angiography and perfusion imaging for cerebral revascularization (5R01NS118019-03). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10401955. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*