by LasikExpert » Mon Mar 31, 2008 4:50 pm
There would be two primary reasons why vision would suddenly improve after eye drops, but quickly dissipate.
The surface of the cornea is a bit rough. The epithelium is the soft pliable outermost layer of the cornea. Corneal epithelial cells are the fastest reproducing cells in the human body, but if they have not fully healed, thickened, and smoothed, then vision quality may be diminished. When you apply an eye drop, all the microscopic cracks and crevasses are filled in by the artificial tears and this creates a smooth surface. This is a sign of dry eyes and/or incomplete healing.
Another change with eye drops is a very small change in the thickness of the cornea (including the tears with eye drops). A full diopter of refractive error is only about 12 microns of thickness - that is about 1/5th the width of a human hair. When you apply artificial tears the thickness of the cornea increases a small amount for a brief period. It may be that you are very slightly over-corrected into hyperopia and the extra thickness brings you back to plano (no refractive error).
Your doctor can advise you on the condition of your epithelium and your current refractive error.