Purpose: A high dose rate (HDR) afterloading technique for prevention of vascular stenosis or occlusion after percutaneous transluminal arteriography and subsequent stent implantation caused by intimal hyperplasia is presented.
Methods and materials: The frequency of recurrent stenosis or occlusion following implantation of stents into peripheral arteries is relatively high. The cause of relapse is rapid intimal hyperplasia. To prevent proliferation of the intimal layer, intravascular brachytherapy was performed in cases of recurrent vascular occlusion or severe stenosis. After recanalization by percutaneous transluminal angioplasty and stent implantation, a 9-French-ReKa catheter was placed within the lumen of the stent. This catheter served as a guide for a 5-French flexible applicator. Then after individual calculation of the isodose, 12 Gy were applied to the vessel wall. This procedure was followed by 72 h of heparinization. Follow-up by Doppler digital subtraction angiography and magnetic resonance imaging was done 3, 6, and 12 months after the procedure and later on once a year.
Results: Intraluminal irradiation was performed in 13 patients (nine male and four female). All patients had a clinically relevant restenosis or reocclusion in the superficial femoral artery (clinical stage according to Fontaine IIb-III). Follow-up time ranged from 3-27 months. After irradiation the stented area remained patent in all cases and there were no signs of recurrent stenosis in the treated arterial segment.
Conclusion: With high dose rate 192Ir afterloading after percutaneous transluminal angioplasty and subsequent stent implantation restenosis or reocclusion caused by intimal hyperplasia can be prevented.