Analysis of The Outcomes of Therapeutic Photorefractive Keratectomy Combined With Prophylactic Accelerated Cross-Linking (PRK-Plus), for Treatment of Thin Suspicious Cornea

Inclusion criteria

• CCT less than 490 microns
• K mean more than 46 and/or K max more than 47.
• Astigmatism cylinder >1.5 D.
• D value of Belin/Ambrósio Module > 1.6
• inferior- superior asymmetry or bow-tie pattern with skewed radial axes on tangential maps and abnormal changes on (BAD).
• Asymmetry topography between 2 eyes, even if neither eye"s topographic pattern is in itself decidedly abnormal.
• Any significant skewed radial axis with or without inferior steepening, or one diopter or more of inferior steepening in some areas but an I-S value of ,1.4,7.
• young patients with against-the-rule astigmatic patterns.
• a PTA value 40% if calculated.
• Abnormal Topographic Patterns
• K2 reading of corneal back surface less than [-7].
• D Value of CSTP > 2.5 in Belin/Ambrósio curve
• We look at values within the central 5 mm circle; the map should be displayed in the BFTE float mode with an estimated area of 8 mm of diameter:

• Elevation values on the front surface values > +12 μ
• Elevation values on the back surface values >+15 μ.
• If there is any isolated island on either front or back surfaces (in the BFS float mode)

Exclusion criteria

• Eyes diagnosed with KC.
• CCT less than 450 microns