Background Sirolimus-eluting stent (SES) is often used for the treatment of paclitaxel-eluting stent (PES) restenosis.The aim of the study was to investigate the neointimal coverage of SES following treatment of PES restenosis using optical coherence tomography (OCT).Methods A total of 9 patients with PES restenosis were treated with SES (Group P).All 9 patients underwent a follow up OCT after 6 months.The OCT findings were compared with those from 8 patients who had a 6 month follow up OCT after SES implantation for de novo lesion (Group S).