Is there evidence for a surgeon learning curve for endothelial keratoplasty in Australia?
OBJECTIVE
Expected outcomes from endokeratoplasty may vary with surgeon experience.


BACKGROUND
It was explored whether a surgeon learning curve exists for Descemet stripping endothelial keratoplasties (manual or automated) performed in Australia.


METHODS
This is a prospective cohort study, with various clinical settings.


METHODS
There were 2139 recipients of 2615 endothelial grafts, registered by 85 surgeons between January 2006 and December 2013.


METHODS
Kaplan-Meier survival analyses and Cox proportional hazards regression were used to examine longitudinal graft survival. Manual and automated Descemet stripping endothelial keratoplasties were analysed together. Pearson chi-squared analyses were performed to examine differences amongst groups. Continuity correction was used for 2 × 2 tests, and statistical significance was set at P < 0.05 (two-sided).


METHODS
The main parameter measured was endothelial graft survival.


RESULTS
Survival of the first 56 registered grafts was significantly poorer than survival of subsequent grafts (χ2= 8.83, df = 1, P = 0.003), when data were combined for all surgeons. Surgeon workload influenced graft survival significantly (P < 0.001). This variable was retained in multivariate analysis designed to investigate independent factors influencing graft survival. Primary non-functioning grafts were significantly less likely to be reported for endokeratoplasties performed by surgeons with more than 56 registered grafts, compared with those registering 56 or fewer grafts (4.3% vs. 8.5%; χ2= 18.38, df = 1, P < 0.001).


CONCLUSIONS
Our findings suggest that for less experienced or low-volume surgeons, longitudinal graft survival improved once 56 or more endokeratoplasties had been performed, indicative of a learning curve. The learning curve was less apparent for surgeons with 57 or more Descemet stripping endothelial keratoplasties and/or Descemet stripping automated endothelial keratoplasties registered during the 8-year study period. Different learning curves may be anticipated for these two groups of surgeons.
Department of Ophthalmology, Flinders University, Adelaide, Australia.
Miriam C
MC
Keane
Department of Ophthalmology, Flinders University, Adelaide, Australia.
Richard Ad
RA
Mills
Department of Ophthalmology, Flinders University, Adelaide, Australia.
Douglas J
DJ
Coster
Department of Ophthalmology, Flinders University, Adelaide, Australia.
Keryn A
KA
Williams
D001315:Australia / Q000453:epidemiology; D002983:Clinical Competence; D003316:Corneal Diseases / Q000601:surgery*; D057111:Descemet Stripping Endothelial Keratoplasty / Q000193:education*; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000453:epidemiology*; D006085:Graft Survival; D006801:Humans; D015994:Incidence; D059032:Learning Curve; D011446:Prospective Studies; D066231:Surgeons / Q000592:standards*; D016526:Workload / Q000706:statistics & numerical data*
DSAEK; DSEK; endokeratoplasty; graft survival; surgeon learning curve