# Contrast Free MRI for Imaging Vascular Calcification in Diabetic Lower Extremity

> **NIH NIH R03** · WASHINGTON UNIVERSITY · 2020 · $78,729

## Abstract

Diabetes is an important independent risk factor for peripheral arterial disease (PAD) and
patients with both PAD and diabetes are more likely to have wound formation, infection, and
higher risk of limb loss. A hallmark of PAD in the setting of diabetes, is the accumulation of densely
calcified, recalcitrant, occlusive disease of the tibial and pedal arteries. However, it is difficult to
non-invasively assess patency of tibial and pedal outflow arteries accurately in the lower
extremities of the patients with diabetes, due to multi-segment, diffuse, and calcified plaques. In
addition, the contrast media used in current clinical diagnostic tools, such as digital subtraction
angiography (DSA), computerized tomographic angiography (CTA), or contrast-enhanced
magnetic resonance angiography, are contraindicated to patients with diabetes who have renal
insufficiency.
 The contrast free magnetic resonance angiography (CF-MRA) becomes a favorable
imaging method in these patients. Current CF-MRA techniques demonstrated good sensitivity
and specificity for the detection of arterial stenosis in lower extremities, but relies on the
electrocardiography (ECG) triggering. Irregular ECG signals in patients with diabetes who are
more likely to be overweight and/or obese results in suboptimal or useless angiographic findings.
More importantly, current CF-MRA techniques have no robust methods to assess the extent of
arterial wall calcification. The objective of this study is to develop and validate a new CF-MRA
technique, without using any ECG signal, to assess both arterial stenosis and calcification.
 Two specific aims will be addressed. In Specific Aim 1, a new CF-MRA technique for
quantitative measurements of arterial outflow vessel stenosis and calcification will be developed
and validated in a 3D printed calcified vascular phantom. In Specific Aim 2, sensitivity and
specificity of vascular calcification and stenosis detection will be determined in the lower
extremities of 25 patients with symptomatic PAD and diabetes using the new CF-MRA technique,
in comparison with CTA and DSA, respectively. It is hypothesized that the extent of calcification
and stenosis degree measured by the new CF-MRA will be strongly correlated with the actual
size of calcification and stenosis in the phantom (r > 0.9). High sensitivity and specificity (> 90%)
will be achieved for the detection of calcification and stenosis with the new CF-MRA. The
completion of this study will build a foundation to comprehensively assess the vasculature in the
lower extremities of patients with PAD and diabetes, which is essential to effective treatment plans
for revascularization and limb salvage.

## Key facts

- **NIH application ID:** 9978782
- **Project number:** 5R03EB028415-02
- **Recipient organization:** WASHINGTON UNIVERSITY
- **Principal Investigator:** JIE ZHENG
- **Activity code:** R03 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $78,729
- **Award type:** 5
- **Project period:** 2019-07-16 → 2022-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9978782

## Citation

> US National Institutes of Health, RePORTER application 9978782, Contrast Free MRI for Imaging Vascular Calcification in Diabetic Lower Extremity (5R03EB028415-02). Retrieved via AI Analytics 2026-05-28 from https://api.ai-analytics.org/grant/nih/9978782. Licensed CC0.

---

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