Long-term functional and anatomical results of osteo- and osteoodonto-keratoprosthesis.
OBJECTIVE
To analyse the functional and anatomical results of keratoprosthesis using tooth and tibial autograft.


METHODS
We reviewed 227 charts of patients that underwent osteo-keratoprosthesis (OKP) (n = 82) or osteo-odonto-keratoprosthesis (OOKP) (n = 145) at the Centro de Oftalmología Barraquer. Mean follow-up time was 8.4 years for OOKP and 3.5 years for OKP. Kaplan-Meier survival curves with 95% confidence interval (CI) were calculated for functional success, defined as BCVA >0.05. Anatomical success was defined as retention of the keratoprosthesis lamina. Visual Acuity by Time (VAT) Index with 95% CI was calculated for up to 2 years post-OKP and up to 6 years post-OOKP. Maximum visual acuity ever reached after the last step of the implantation of the keratoprosthesis was used as an indicator for the potential of the retina.


RESULTS
Based on Kaplan-Meier analyses, 10-year anatomical survival was 66% (CI 57-76) for OOKP and 47% (CI 27-67) for OKP. Two-year functional survival was 63% (CI 55-71) for OOKP and 49% (CI 37-60) for OKP, and 10-year functional survival was 38% (CI 29-48) for OOKP and 17% (CI 5-28) for OKP. Multivariate analysis showed that neither surgical technique (OOKP or OKP), primary diagnosis nor age had a significant influence on the functional survival. However, a high maximum visual acuity ever reached post-op decreased the risk for functional failure. According to the VAT Index calculations, mean BCVA 2 years after OOKP was 0.33 (CI 0.28-0.41) and after OKP was 0.28 (CI 0.20-0.36).


CONCLUSIONS
Although we found a tendency that OOKP had better anatomical results than OKP, this difference was not statistically significant up to 10 years post-op. Functional results for both techniques were not significantly different at the 2-year follow-up, but at 10 years they were. However, this difference was influenced by the retinal potential and not by the technique itself.
Michael
Ralph
R
Institut Universitari Barraquer, Laforja 88, E-08021, Barcelona, Spain. ralphm@barraquer.com
Charoenrook
Victor
V
de la Paz
Maria Fideliz
MF
Hitzl
Wolfgang
W
Temprano
Jose
J
Barraquer
Rafael I
RI
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003316:Corneal Diseases / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006085:Graft Survival / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D013508:Ophthalmologic Surgical Procedures; D019919:Prosthesis Implantation; D012189:Retrospective Studies; D013977:Tibia / Q000637:transplantation*; D014092:Tooth Root / Q000637:transplantation*; D014182:Transplantation, Autologous; D014792:Visual Acuity / Q000502:physiology*