Novel Applications of Radionuclide Imaging in Peripheral Vascular Disease

Abstract

Peripheral vascular disease (PVD) is a progressive atherosclerotic disease that leads to stenosis or occlusion of blood vessels supplying the lower extremities. Current diagnostic imaging techniques commonly focus on evaluation of anatomy or blood flow at the macrovascular level and do not permit assessment of the underlying pathophysiology associated with disease progression or treatment response. Molecular imaging with radionuclide-based approaches can offer novel insight into PVD by providing noninvasive assessment of biological processes such as angiogenesis and atherosclerosis. This article discusses emerging radionuclide-based imaging approaches that have potential clinical applications in the evaluation of PVD progression and treatment.

Keywords: Angiogenesis; Atherosclerosis; Molecular imaging; PET; Perfusion; Peripheral vascular disease; SPECT.

Figure 1

Sagittal view of ^99mTc-tetrofosmin SPECT imaging in a patient with non-healing heel ulcer before (A) and after (B) lower extremity revascularization and wound debridement demonstrates increased tracer uptake in the heel and distal foot. Pre-revascularization regions of ischemia are identified by white arrows and improvements in post-revascularization perfusion are denoted by yellow arrows.

Figure 2

Trasverse (A), coronal (B), and sagittal (C) views of angiogenesis targeted imaging in a pig model of unilateral hind limb ischemia using ^99mTc-NC100692 SPECT/CT demonstrates marked tracer uptake in ischemic tissue 2 weeks following femoral artery occlusion.

Figure 3

Targeted imaging of atherosclerosis in the common iliac arteries using CT (A), ¹⁸F-NaF PET (B), and fused ¹⁸F-NaF PET/CT imaging (C). Fused imaging demonstrates ¹⁸F-NaF accumulation in atherosclerotic lesion of iliac artery that is co-localized with calcification. Arrows indicate region of calcified lesion. From Derlin et al. Feasibility of 18F-Sodium Fluoride PET/CT for Imaging of Atherosclerotic Plaque. J Nucl Med 2010;51:862-5; with permission.

Figure 4

A) Volume rendering of ¹⁸F-FDG PET/CT demonstrates focal uptake of tracer in regions of mitral valve (arrowhead), L4 to L5 discus (thin arrow), and right femoral artery stent (thick arrow) in a patient found to have mitral endocarditits, peridural abscess, and stent dislocation and fracture. Transverse images further reveal focal ¹⁸F-FDG uptake in the infected (B) mitral valve and (C) femoral artery stent. From Berard X, Pinaquy J-B, Stecken L, et al. Use of 18F-fluorodeoxyglucose positron emission tomography-computed tomography and sonication for detection of infection after peripheral stent fracture. Circulation 2014;129:2437-9; with permission.