Corneal collagen cross-linking for ectasia after excimer laser refractive surgery: 1-year results.
OBJECTIVE
To evaluate the 1-year results of corneal collagen cross-linking (CXL) in eyes with postoperative excimer laser refractive surgery corneal ectasia.


METHODS
Thirteen eyes of 9 consecutive patients who had undergone excimer laser refractive surgery (photorefractive keratectomy [n = 3], LASIK [n = 10]) with resultant unstable corneal ectasia underwent CXL with photosensitizing riboflavin 0.1% solution and subsequent exposure to ultraviolet radiation. Study eyes underwent complete ophthalmologic examination, endothelial specular microscopy, corneal topography, and aberrometry as well as central pachymetry and Scheimpflug-based topo/tomography preoperatively and at 3-, 6-, and 12-month intervals.


RESULTS
Best spectacle-corrected visual acuity (BSCVA) improvement was statistically significant (P < .05) beyond 6 months after surgery (improvement of 0.1 logMAR at 1 year). Mean spherical equivalent refraction and mean refractive sphere reduction (improvement of 1.40 and 1.44 diopters [D], respectively) were statistically significant (P < .05) at 6 months postoperatively. At 1 year after CXL, mean endothelial cell count and keratometry (average SimK decrease of 2.02 D) as well as Klyce and Ambrósio indices did not deteriorate. Coma and spherical aberration did not change significantly. Mean pupil center pachymetry and corneal thickness at 0 and 2 mm from the thinnest corneal point decreased significantly.


CONCLUSIONS
One year after surgery, CXL appears to stabilize eyes with ectasia consequent to excimer laser refractive surgery and improve BSCVA.
Vinciguerra
Paolo
P
Department of Ophthalmology, Istituto Clinico Humanitas, Rozzano, Milan, Italy. info@vincieye.it
Camesasca
Fabrizio I
FI
Albè
Elena
E
Trazza
Silvia
S
D000328:Adult; D002452:Cell Count; D003094:Collagen / Q000378:metabolism*; D003316:Corneal Diseases / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D003319:Corneal Stroma / Q000378:metabolism*; D019781:Corneal Topography; D057108:Corneal Wavefront Aberration; D003432:Cross-Linking Reagents / Q000378:metabolism / Q000627:therapeutic use*; D004108:Dilatation, Pathologic / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism; D004728:Endothelium, Corneal / Q000473:pathology; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D054018:Lasers, Excimer / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy; D018903:Photorefractive Keratectomy; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011183:Postoperative Complications; D011446:Prospective Studies; D012256:Riboflavin / Q000008:administration & dosage; D014466:Ultraviolet Rays; D014792:Visual Acuity / Q000502:physiology
D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin