Ocular Surface Analysis After Small-Incision Lenticule Extraction
Narrative Responses:
Purpose
Dry eye is the most common complication after refractive surgery and can affect quality of vision and quality of life. LASIK inherently causes the transection of afferent sensory nerve fibers and decrease of corneal sensitivity. Our purpose was to investigate ocular surface modifications after flap-less refractive surgery with lenticule extraction (SMILE).
Methods
Sixteen eyes of eight patients treated with SMILE, were examined one month after surgery. Patients completed the Ocular Surface Disease Index (OSDI) questionnaire and underwent Schirmer test, corneal staining, tear break-up time (BUT), tear osmolarity, corneal esthesiometry, in vivo confocal microscopy and anterior segment spectral domain OCT imaging.
Results
Mean values were: OSDI score: 17.2, tear osmolarity :301.5 mOsm/L (286-311), Schirmer test 13.83 mm (7-30), BUT 5.75 seconds (4-8) showing a moderate dry eye syndrome one month after surgery. Mean esthesiometric result was 1.625 . All patients stopped dry eye treatment after one month. OCT spectralis showed normal corneal structures and a high degree of predictability of the incision. Confocal microscopy showed keratocytes high reflectivity that could be the expression of keratocyte activation and presence of subbasal nerve fibers early after surgery.
Conclusion
As dry eye is the most important reason of dissatisfaction after refractive surgery, SMILE technique appears as an interesting alternative to LASIK to prevent from post operative dry eye.