Magnetic Resonance Imaging Techniques in Peripheral Arterial Disease

Area of Science:

• Biomedical Imaging
• Vascular Medicine
• Metabolic Research

Background:

• Peripheral arterial disease (PAD) poses a global health burden, with diabetes exacerbating its progression and leading to severe complications like limb loss.
• Current diagnostic methods for PAD, including conventional MRI, primarily focus on macrovascular assessment and have limitations in capturing the disease's complex mechanisms.
• There is a critical need for imaging modalities that can evaluate the interplay between impaired blood flow, microvascular perfusion, and skeletal muscle metabolism in PAD.

Purpose of the Study:

• To review recent advances in magnetic resonance imaging (MRI) for assessing peripheral arterial disease (PAD).
• To highlight novel noncontrast MRI techniques for evaluating skeletal muscle perfusion and metabolism in PAD.
• To discuss the critical issues and future directions in advanced MRI for PAD management.

Main Methods:

• Review of conventional MRI techniques (contrast-enhanced MRA, noncontrast TOF MRA, phase contrast MRI) and their limitations.
• Introduction of novel noncontrast MRI methods including arterial spin labeling (ASL), blood-oxygen-level dependent (BOLD) imaging, and chemical exchange saturation transfer (CEST).
• Discussion of the necessity for modalities assessing macrovasculature, microvasculature, and muscle metabolism in PAD.

Main Results:

• Conventional MRI techniques for macrovascular assessment have significant limitations in fully characterizing PAD.
• Emerging noncontrast MRI techniques like ASL, BOLD, and CEST show promise in assessing skeletal muscle perfusion and metabolism.
• These advanced methods address the limitations of conventional imaging by evaluating complex interactions within PAD.

Conclusions:

• Novel noncontrast MRI techniques are crucial for a comprehensive understanding of PAD pathophysiology.
• Further development and clinical validation of ASL, BOLD, CEST, and other advanced MRI methods are essential.
• These advanced modalities hold potential for improved prognostic data and outcome surveillance in PAD patients.