Non Invasive Tear Film Break-Up Time Evaluation by Real-Time Wavefront Aberrometry After LASIK Surgery

Abstract

Purpose: : To evaluate tear break-up time (BUT) with real-time (RT) higher order wavefront aberrations (HOA) measurements in myopic patients after Laser-Assisted In Situ Keratomileusis (LASIK) surgery.

Methods: : Wavefront aberrations up to the sixth order for a 4-mm pupil were measured in 20 normal subjects (Group 1) and in 20 myopic patients, with no history of dry eye (DE), before and after LASIK surgery (Group 2), using the IRX3 (Imagine Eyes, Orsay, France) Hartmann-Shack (H-S) aberrometer. The HOA measurements were performed (in triplicate) with a new dedicated software, once every second for up to 20 seconds. HOA variations were compared with the BUT by the conventional fluorescein method (CFM).

Results: : Twenty percent of the patients from Group 2 were complaining from DE symptoms. There was an excellent correlation between the HOA variation and the BUT recorded by the CFM in both groups. There was also an excellent reproducibility of the HOA measurements in all subjects and patients. BUT was significantly decreased (P<0.005) in 30% of the patients in Group 2 when compared to the normal tests subjects (Group 1).

Conclusions: : The IRX3 H-S aberrometer can be used for an objective and reproducible assessment of the BUT in the follow-up of patients after LASIK surgery.

Keywords: refractive surgery: LASIK • cornea: tears/tear film/dry eye • aberrations