Efficiency in Skill Development of Pterygium Excision with Amniotic Membrane Transplantation among the 1st Year Ophthalmology Residents

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kittichai akrapipatkul



Purpose: To evaluate the learning curve of pterygium excision with amniotic membrane transplantation among the first year ophthalmology residents.

Methods: Prospective comparative study. Four first year ophthalmology residents were monitored for operating times and recurrence rates on all their cases of pterygium excision with amniotic membrane transplantation throughout one year. Data for baseline characteristics of patients with continuous data were analyzed for differences among residents using one-way ANOVA. Proportional data such as gender and recurrence rates, were analyzed for differences among residents using fisher’s exact test. Average predicted operating times with consecutive cases were analyzed using linear regression. Operating time stabilization with consecutive cases is visualized by a Locally Weighted Scatterplot Smoothing (LOWESS) and quadratic best fit lines.  


Results: A total of 159 eyes (159 patients) with primary pterygium excision was performed with sutured amniotic membrane transplantation. All cases were attributed to four ophthalmology residents composed of 40, 41, 42 and 36 patients. The average operating time was 50.38 ± 13.92 minutes, with a range of 28 to 100 minutes. The operating time declined in proportion to the number of patients and stabilized after 38 cases, averaging 43.33 ± 18.93 minutes. The pterygium recurrence rate found in this study was 11.94% 


Conclusions: Pterygium excision with sutured amniotic membrane transplantation is considered an appropriate training procedure for ophthalmology residency training due to the duration needed to reach the learning curve. Additionally, the rate of recurrence among residents is comparable to that of other similar studies. 

Keywords: learning curve, operating time, pterygium excision, amniotic membrane transplantation, recurrent pterygium

Ethics: This study was approved for ethical research in human with the human research ethics committee of Thammasat university, Thailand (Research ID: MTU-EC-OP-0-105/56)



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