Simultaneous 18-FDG PET and MR imaging in lower extremity arterial disease

Area of Science:

• Medical Imaging
• Cardiovascular Disease
• Nuclear Medicine

Background:

• Simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) is a novel hybrid imaging modality.
• This technique combines MRI's morphological detail with PET's pathophysiological insights.

Purpose of the Study:

• To evaluate simultaneous 18-Fluorodeoxyglucose (18-FDG) PET/MR imaging for characterizing atherosclerotic lesions.
• To assess the utility of this hybrid imaging in lower extremity arterial disease (LEAD).

Main Methods:

• Eight patients with symptomatic superficial femoral artery (SFA) stenosis underwent simultaneous 18-FDG PET and contrast-enhanced MRI.
• Invasive plaque characterization was performed using optical coherence tomography (OCT).
• Histological analysis of plaque specimens was conducted post-atherectomy.

Main Results:

• MRI demonstrated significant contrast enhancement in stenotic SFA segments compared to controls.
• 18-FDG uptake was observed in most symptomatic stenoses (TBR > 1).
• FDG uptake correlated with plaque composition: higher in active fibroatheroma, lower in fibrocalcified lesions.

Conclusions:

• Simultaneous 18-FDG PET/MR imaging is feasible for evaluating LEAD.
• This multimodal approach may offer new insights for risk estimation in LEAD patients.
• Challenges and potential benefits of this technique were highlighted.