Enhancement of refractive outcomes of small-incision lenticule extraction via tear-film control

Il Hwan Koh, Kyoung Yul Seo, Seong Bae Park, Hun Yang, In Sik Kim, Sang Min Nam

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


Purpose: To suggest that tear film is a refractive outcome predictor in small-incision lenticule extraction (SMILE) for myopia and describe methods of controlling the tear film and its effects on refractive outcomes. Methods: In this retrospective case–control study, the tear film was kept clear and appropriate in amount during tear-film-controlled SMILE (TFC-SMILE). In contrast, no special care to the tear film was given in direct-docking SMILE (DD-SMILE). Both procedures were performed by the same experienced surgeon, using the same surgical parameters, over defined periods. In select cases, scanning electron microscopy (SEM) of the lenticule and surgical videos of opaque bubble layers (OBLs) were obtained and compared. Results: Forty-one eyes had DD-SMILE and 55 eyes had TFC-SMILE. Multivariate analysis showed that TFC-SMILE and the patient’s age were significant predictors of refractive outcomes. The refractive predictability of TFC-SMILE was better than that of DD-SMILE, and under-correction of high myopia was evident in the latter patients. The predictive errors of DD-SMILE became more myopic and variable during 1 year than those of TFC-SMILE. The lenticular surface on SEM was more serrated in DD-SMILE. Severe OBLs were evident in four cases of DD-SMILE and the OBL pattern was sporadic at the anterior surface of the lenticule. Conclusions: The presence of a clear and appropriate tear film in SMILE enhanced predictability, minimized variability, and ensured stability of refractive outcomes. An uncontrolled tear film might render cutting imprecise and trigger severe OBL formation. TFC-SMILE had more predictable results than DD-SMILE.

Original languageEnglish
JournalGraefe's Archive for Clinical and Experimental Ophthalmology
Publication statusAccepted/In press - 2018

Bibliographical note

Publisher Copyright:
© 2018, Springer-Verlag GmbH Germany, part of Springer Nature.

All Science Journal Classification (ASJC) codes

  • Ophthalmology
  • Sensory Systems
  • Cellular and Molecular Neuroscience


Dive into the research topics of 'Enhancement of refractive outcomes of small-incision lenticule extraction via tear-film control'. Together they form a unique fingerprint.

Cite this