Intima Versus Adventitia Drug Delivery to Elucidate Mechanisms of Restenosis: Magnetic Resonance Imaging

Inclusion Criteria: Screening: 1. Male or non-pregnant female ≥ 35 years of age 2. Atherosclerotic, infrainguinal PAD 3. Rutherford Clinical Category 2-6 4. Stenosis detected by radiology that in the clinician's opinion is the reason for the PAD symptoms 5. Patient is willing to provide informed consent and comply with the required follow up visits, testing schedule, and medication regimen 6. Estimated Glomerular Filtration Rate (eGFR) ≥ 30 and/or threshold established by the local Institutional Review Board or Committee of Human Research Procedural Criteria: 1. De novo atherosclerotic lesion qualifying for angioplasty 2. A patent artery proximal to the index lesion. Concomitant inflow procedures, including open femoral artery endarterectomy and/or stenting of the iliac arteries, are permissible. 3. \>50% diameter stenosis of the superficial femoral artery and/or popliteal artery (between the profunda and tibioperoneal trunk) 4. Reference vessel diameter ≥3 mm and ≤ 8mm 5. Successful wire crossing of lesion 6. Successful angioplasty of the index lesion or part of the index lesion, defined as ≤30% residual lumen stenosis compared with adjacent non-diseased lumen diameter, without flow-limiting dissection Exclusion Criteria: Screening Criteria: 1. Any contraindication to receiving an MRI 2. Pregnant, nursing, or planning on becoming pregnant in \< 2yrs 3. Life expectancy of \< 1 yr 4. History of solid organ transplantation 5. Patient actively participating in another investigational device or drug study 6. History of hemorrhagic stroke within 3 months of index procedure 7. Previous or planned surgical or interventional procedure within 30 days of index procedure 8. Chronic renal insufficiency with eGFR \< 30 9. Prior bypass surgery, stenting, atherectomy or angioplasty of the index lesion 10. Inability to take required study medications 11. Contra-indication or known hypersensitivity to dexamethasone sodium phosphate, contrast media, gadolinium, aspirin or Plavix 12. Systemic fungal infection 13. Acute limb ischemia 14. Prior participation of the index limb in the current study (contralateral treatment is allowed) 15. Patient is being treated with long-term steroids (not including treatment of a bronchial condition with inhaled steroids) Procedural Criteria: 1. Index lesions extending into the tibial trifurcation or above the profunda. Note: the outflow tibial artery can be treated concomitantly. Similarly, the common femoral artery can be treated concomitantly, either with open endarterectomy and patch angioplasty or with endovascular methods. However, the index lesion cannot be contiguous with either the common femoral artery or the tibial trifurcation. 2. Circumferential calcification at index lesion, which in the judgment of the investigator would prevent penetration of the Micro-Infusion catheter needle through the vessel wall 3. Inadequate distal outflow defined as no patent tibial arteries (\>50% stenosis). The outflow vessel can be established at the time of primary treatment 4. Use of adjunctive therapies other than angioplasty. Chocolate balloons and/or scoring balloons are allowed, if used below reference diameter.