Nikolaos Galanakis1, Thomas G Maris2, Nikolaos Kontopodis3, Christos V Ioannou3, Konstantinos Tsetis1, Apostolos Karantanas1, Dimitrios Tsetis4. 1. Department of Medical Imaging, University Hospital Heraklion, University of Crete Medical School, Voutes, 71110 Heraklion, Greece. 2. Department of Medical Physics, University Hospital Heraklion, University of Crete Medical School, Voutes, 71110 Heraklion, Greece. 3. Vascular Surgery Unit, Department of Cardiothoracic and Vascular Surgery, University Hospital Heraklion, University of Crete Medical School, Voutes, 71110 Heraklion, Greece. 4. Department of Medical Imaging, University Hospital Heraklion, University of Crete Medical School, Voutes, 71110 Heraklion, Greece. Electronic address: tsetisd@uoc.gr.
Abstract
PURPOSE: Imaging modalities such as CTA and MRA provide significant information about the distribution of macrovascular lesions of the limbs in patients with peripheral arterial disease but not for the local microvascular perfusion of the feet. The purpose of this study is to evaluate foot perfusion in patients with critical limb ischemia (CLI) and estimate percutaneous transluminal angioplasty (PTA) results, using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). METHODS: Ten patients (6 male, median age 68 years) with CLI were examined. All patients underwent DCE-MRI of the lower limb before and within first month after PTA. Perfusion parameters such as blood flow (BF), Ktrans, Kep were analyzed and applied for statistical comparisons. The studies were also examined by a second observer to determine inter-observer reproducibility. RESULTS: Revascularization was technically successful in all patients and mean ankle brachial index (ABI) increased from 0.37 ± 0.18 to 0.76 ± 0.23, p < 0.05. After PTA, mean BF increased from 6.232 ± 2.867-9.867 ± 2.965 mL/min/100 g, Ktrans increased from 0.060 ± 0.022 to 0.107 ± 0.041 min-1 and Kep increased from 0.103 ± 0.024 to 0.148 ± 0.024 min-1, p < 0.05. All measurements demonstrated very good inter-observer reliability with an ICC > 0.85 for all perfusion parameters. CONCLUSIONS: DCE-MRI is a safe and reproducible modality for the diagnosis of foot hypo-perfusion. It seems also to be a promising tool for evaluation of PTA outcome, as significant restitution of perfusion parameters was observed after successful revascularization.
PURPOSE: Imaging modalities such as CTA and MRA provide significant information about the distribution of macrovascular lesions of the limbs in patients with peripheral arterial disease but not for the local microvascular perfusion of the feet. The purpose of this study is to evaluate foot perfusion in patients with critical limb ischemia (CLI) and estimate percutaneous transluminal angioplasty (PTA) results, using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). METHODS: Ten patients (6 male, median age 68 years) with CLI were examined. All patients underwent DCE-MRI of the lower limb before and within first month after PTA. Perfusion parameters such as blood flow (BF), Ktrans, Kep were analyzed and applied for statistical comparisons. The studies were also examined by a second observer to determine inter-observer reproducibility. RESULTS: Revascularization was technically successful in all patients and mean ankle brachial index (ABI) increased from 0.37 ± 0.18 to 0.76 ± 0.23, p < 0.05. After PTA, mean BF increased from 6.232 ± 2.867-9.867 ± 2.965 mL/min/100 g, Ktrans increased from 0.060 ± 0.022 to 0.107 ± 0.041 min-1 and Kep increased from 0.103 ± 0.024 to 0.148 ± 0.024 min-1, p < 0.05. All measurements demonstrated very good inter-observer reliability with an ICC > 0.85 for all perfusion parameters. CONCLUSIONS:DCE-MRI is a safe and reproducible modality for the diagnosis of foot hypo-perfusion. It seems also to be a promising tool for evaluation of PTA outcome, as significant restitution of perfusion parameters was observed after successful revascularization.