Subconjunctival dexamethasone implant lowers risk of graft rejection after penetrating keratoplasty

Single-centre, phase II non-randomised tolerance and safety pilot study (NCT02834260). Designed to analyse the risk of elevated intraocular pressure (IOP), discomfort and resorption time. Fourteen patients with a low rejection risk indication of PK were enrolled between January 2017 and August 2018. The implant was injected in the 12 o'clock position, 5 mm from the limbus, at the end of PK. A steroid eye-drop treatment was planned when implant resorption was complete. Patients were monitored regularly for 12 months: IOP (main outcome measure at 1 month), discomfort and redness scores, implant status, rejection episode and central corneal thickness by optical coherence tomography. An independent data safety monitoring committee verified safety aspects.

Results:

No increase in IOP or other adverse event related to the implant was observed. Average resorption time was 6 weeks. The switch to steroid eye-drops was uneventful. One patient, included despite preoperative corneal neovascularisation (unintended protocol deviation) experienced a rejection.

This is the first proof of concept that dropless immunosuppression is possible after low rejection risk PK.

Reference:

Trone MC, Poinard S, Crouzet E, Garcin T, Mentek M, Forest F, Matray M, Thuret G, Gain P. Dropless penetrating keratoplasty using a subconjunctival dexamethasone implant: safety pilot study. Br J Ophthalmol. 2023 Feb;107(2):181-186. doi: 10.1136/bjophthalmol-2021-319376. Epub 2021 Aug 23. PMID: 34426402.

Keywords:

British Journal of Ophthalmology, Subconjunctival, dexamethasone, implant, safe, well-tolerated immunosuppressive, therapy, patients, low-rejection, risk, PK, Trone MC, Poinard S, Crouzet E, Garcin T, Mentek M, Forest F, Matray M, Thuret G, Gain P.