Abstract
Purpose: :
To evaluate the clinical effectiveness of the SCREENING in prediction of post-LASIK OS complication (Secondary Dry Eye (SDE), neurotrophic epitheliopathy (NE) or their combination (SDE+NE)) in CL wears.
Methods: :
158 myopic soft CL wears (316 eyes, mean SE -6.78±1.12 D, mean CL wearing 6.31±0.92 years) were examined with SCREENING which included: the confocal microscopy (CM) of cornea and biochemical analysis of lachrymal fluid with calculation of the previously elaborated Coefficient (C=M/A×1000, M - urea concentration [mmol/l], A- α-amylase activity [Un/l], C>30 means CL intolerance, 15>C>30 - OS sub-compensation, C<15 - CL tolerance) before LASIK. As a Control Group: 161 myopic CL wears (322 eyes, mean SE -6.51±1.09 D, mean CL wearing 5.91±0.88 years) were operated with LASIK after standard examination.
Results: :
In 10.1% CM and C were normal or subnormal (Group1); in 60.8% - C revealed the OS sub-compensation, CM: epithelial pseudokeranization, stromal "active cells", sub-bowmen plexus nerves activation, endothelial polymorphism (Group2); in 29.1% - C revealed the CL intolerance, in the CM a lot of dendritic cells at the bowmen’s membrane level as well as the extensive extracellular matrix oedema were added (Group3). LASIK in Groups 1 and 2 were uneventful, in Group 3 - epithelial defects in 4.3%. Post-op: in Group1 - SDE - 6.2%, 93.8% - no OS complications; in Group2: SDE - 7.3%, NE - 18.8%, NE+SDE - 16.7%, 57.2% - no complications; in Group3: SDE - 33.7%, NE - 22.8%, SDE+NE - 41.3%, 2.2% - no complications; in the Control Group: SDE - 18.3%, NE - 9.6%, SDE+NE - 19.9%, 52.2% - no complications.
Conclusions: :
The SCREENING is an effective tool for the preoperative prediction of post-LASIK OS complication, such as SDE, NE or SDE+NE and could be useful for the electing the high risk patients among the CL wears who are going to have LASIK.
Keywords: contact lens • microscopy: confocal/tunneling • refractive surgery: complications