Need for explantation of an intrastromal titan ring after penetrating keratoplasty in two patients

The most severe complications after penetrating keratoplasty (PKP) include high astigmatism and immunological graft reaction. The introduction of the corneal intrastromal titan ring by Krumeich intended to reduce the incidence of both complications. We present two patients with keratoconus who referred to our department after a PKP combined with the implantation of an intrastromal ring. The first patient suffered from bulbar pain and headaches. The second patient suffered from postoperative high myopia, irregular astigmatism and was contact lens intolerant. In the first patient we recognized anterior movement of the ring inside the stroma and decided to remove it. The second patient was found to have extreme bulging of the transplant. We removed the ring and sequentially performed a repeat-PKP. In both patients the implantation of the ring failed to decrease the postoperative astigmatism and caused symptoms that affected the patients' everyday life. Therefore, we recommend not to use this titan ring.

Keywords: Keratoconus; astigmatism; immune reaction; intrastromal titan ring explantation.