Tissue-Muscle Perfusion Scintigraphy of the Lower Limbs in a Patient with Type 2 Diabetes Mellitus and Peripheral Arterial Disease

Abstract

The estimation of tissue perfusion as a hemodynamic consequence of peripheral arterial disease (PAD) in diabetic patients is of great importance in the management of these patients.We present a noninvasive, functional method of 99mTc-MIBI (methoxy-isobutyl-isonitrile) tissue-muscle perfusion scintigraphy (TMPS) of the lower limbs, which assesses tissue perfusion in basal conditions ("rest" study) and exercise conditions ("stress" study). Emphasis is given on perfusion reserve (PR) as an important indicator of preservation of microcirculation and its local autoregulatory mechanisms in PAD. We present a case of a 71-year-old male diabetic patient with skin ulcers of the right foot and an ankle-brachial index >1.2 (0.9-1.1). Dynamic phase TMPS of the lower limbs showed decreased and late arterial vascularization of the right calf (RC) with lower percentage of radioactivity in the 1st minute: RC 66%, left calf (LC) 84%. PR was borderline with a value of 57% for LC and decreased for RC (42%). Functional assessment of hemodynamic consequences of PAD is important in evaluating both advanced and early PAD, especially the asymptomatic form. The method used to determine the TMPS of the lower limbs, can differentiate subtle changes in microcirculation and tissue perfusion.