OBJECTIVE To describe the visual and refractive outcomes in three eyes (two keratoconic patients) with previous intrastromal corneal ring segments (INTACS, Addition Technology Inc) that underwent adjuvant single KeraRing (Mediphacos) intrastromal corneal ring segment implantation. METHODS Two keratoconic patients (three eyes) with implanted INTACS segments underwent an additional (without explanting previous INTACS) single KeraRing segment implantation. RESULTS No intraoperative complications occurred. Six months postoperatively, uncorrected distance visual acuity improved from 20/100 and 20/200 to 20/32 and 20/40 in the right and left eyes, respectively, of patient 1, and from 20/400 to 20/50 in the treated right eye of patient 2. Corrected distance visual acuity improved from 20/50 and 20/100 to 20/30 and 20/32 in the right and left eyes, respectively, of patient 1 and from 20/200 to 20/40 in patient 2. Keratometric measurements improved from 51.00/45.70 to 47.00/44.60 diopters (D) and from 50.80/48.80 to 42.70/40.30 D in the right and left eyes, respectively, of patient 1, and from 49.30/45.70 to 45.60/44.10 D in patient 2. CONCLUSIONS In keratoconic patients with INTACS in place, adjuvant single intrastromal corneal ring segment (KeraRing) implantation could improve visual and refractive outcome.