To report the clinical results after the implantation of intrastromal corneal ring segments (Intacs®) by manual tunnel creation for the correction of keratoconus.

This retrospective case series was comprised of 10 eyes of 8 consecutive keratoconic patients. Visual acuity, refractive outcome, keratometric values, anterior chamber depth, central corneal thickness, and endothelial cell density were evaluated before and at 1 month, 3 months, and 6 months postoperatively. In addition, the implanted ring segment depth was measured by anterior segment optical coherence tomography at postoperative 6 months. Any postoperative complications were also recorded.

Visual acuity was improved in 9 out of 10 eyes. Spherical equivalent and keratometric values were decreased in all eyes. There was no significant difference in central corneal thickness, but endothelial cell density and anterior chamber depth were slightly decreased. The depth of ring segments was almost constant at superior, middle, and inferior. There was a single case of descented implanted ring segments and 6 cases of stromal infiltration around ring segments, but visual acuity was unaffected. In addition, 1 case showed implanted ring exposure, thus the superior ring segment was removed at postoperative 4 months.

Intrastromal corneal ring segment implantation (Intacs®) by manual tunnel creation appears to be effective in improving the visual acuity and stabilizing corneal refractive power in keratoconic patients.