Gibbons A, et al. - The indications, long-term clinical and visual outcomes, and complications of the aphakic snap-on type I Boston keratoprosthesis (KPro) were determined by the experts. After the implantation of the aphakic, snap-on type I KPro, most subjects experienced improved visual acuity. However, correlating with the onset of postoperative complications, the visual gains were not sustained over time.