Radiotracer-Based Perfusion Imaging of Patients With Peripheral Arterial Disease

Radiotracer-Based Imaging for Quantitative Assessment of Angiosome Perfusion Following Lower Extremity Revascularization

The aim of this clinical study is to assess the prognostic value of radiotracer-based perfusion imaging for predicting clinical outcomes in diabetic patients with peripheral arterial disease (PAD) who are undergoing lower extremity revascularization procedures. We hypothesize that radiotracer imaging of the lower extremities will provide a sensitive non-invasive imaging tool for assessing regional abnormalities in foot/calf muscle perfusion and evaluating treatment responses.

PAD patients (n=200) with peripheral arterial disease (PAD) who are scheduled to undergo lower extremity revascularization procedures will be recruited. Patients will be screened using a standard medical history questionnaire and a physical activity questionnaire. Once their questionnaires are reviewed, individuals who meet inclusion criteria will proceed with standard PAD screening, which will include Ankle-Brachial Indices (ABIs) and Toe-Brachial Indices (TBIs) of both lower extremities. Patients will undergo SPECT/CT or PET/CT perfusion imaging prior to their revascularization procedure and 1-14 days following revascularization. Subjects will receive an intravenous injection of a standard clinical dose of radiotracer for both imaging sessions. A low-dose CT scan will be performed immediately after each SPECT and PET image acquisition for the purposes of attenuation correction and regional analysis of radiotracer uptake. Clinical outcomes will be evaluated for up to 12 months after the imaging study to assess the prognostic value of perfusion imaging for predicting subsequent outcomes.

Patients with peripheral arterial disease will have already been scheduled for clinically indicated revascularization procedures of the lower extremity and undergo SPECT/CT imaging as part of the research protocol.

Patients with peripheral arterial disease will have already been scheduled for clinically indicated revascularization procedures of the lower extremity and undergo PET/CT imaging as part of the research protocol.

Subjects will receive a standard clinical dose of a radionuclide for perfusion imaging of the lower extremities before and after revascularization procedures.

Subjects will receive a standard clinical dose of a radionuclide for perfusion imaging of the lower extremities before and after revascularization procedures.

The percent or absolute change in perfusion from baseline to post-revascularization will be evaluated.

Inclusion Criteria: At least 18 years of age Evidence of significant obstructive disease for one or multiple lower extremity arteries, as identified by prior ABI, TBI, CT angiography, ultrasound, or MR imaging. Exclusion Criteria: Unable to give informed consent or follow-up Pregnant or nursing Under the age of 18 No history of peripheral arterial disease

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