[Corneal Cross-linking for the treatment of keratoconus: preliminary results].
OBJECTIVE
To present early visual and keratometric results for corneal cross-linking with riboflavin and UV irradiation in patients with progressive keratoconus.


METHODS
Twenty-five eyes of twenty patients (15 males and 5 females) with a progressive keratoconus in the previous 6 months were followed. Unaided visual acuity (UVA), best spectacle corrected visual acuity (BSCVA), spherical equivalent (SEQ), manifest cylinder, and maximal corneal curvature (max K) values were followed at 1, 3 and 6 months. All patients were submitted to corneal cross-linking using riboflavin (vitamin B2) as the photosensitizer and ultraviolet light (UV, wavelength 370 nm). Epithelium was removed with 20% alcohol, cornea was soaked with vitamin B2 for 15 min, and then irradiated with UV light for 30 min, after which a bandage contact lens (BCL) was placed.


RESULTS
UVA increased after one month (from 0.15 +/- 0.15 to 0.23 +/- 0.20), and went on increasing at 3 and 6 months, reaching statistical significance (p=0.025 e p=0.037, respectively). BSCVA increased from 0.41 +/- 0.27 to 0.49 +/- 0.29 at month six, without reaching statistical significance at any time point. Progression of keratoconus stopped in all patients, in contrast with progression in all of them in the six-month period prior to the surgery. Max K decreased by more than 2 D (from 53.02 +/- 8.42 to 50.88 +/- 6.05 D), SEQ less that 1 D (from -3.27 +/- 4.08 to -2.68 +/- 3.02 D), while refractive cylinder decreased less than 0.5 D (from -2.29 +/- 1.77 to -1.86 +/- 0.92 D), without reaching a statistically significant difference. None of the eyes lost any line of BSCVA, 12 maintained the preoperative BSCVA, 7 gained one line, 5 gained two lines, and 1 patient gained three lines of BSCVA.


CONCLUSIONS
Corneal cross-linking with riboflavin and UV light seems to be a safe (no loss of BSCVA) and effective (anatomical and optical properties maintained) procedure, which has shown to stop the progression of the keratoconus: a reduction, although not statistically significant, of the corneal curvature, spherical equivalent and refractive cylinder took place in patients where previous progression of keratoconus had been described.
Jankov
Mirko R
MR
Laser Focus, Belgrado, Sérvia. visioncare@mac.com
Hafezi
Farhad
F
Beko
Maja
M
Ignjatovic
Zora
Z
Djurovic
Branislav
B
Markovic
Vujica
V
Schor
Paulo
P
D000328:Adult; D003094:Collagen / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D003319:Corneal Stroma / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000188:drug therapy / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D012029:Refraction, Ocular / Q000187:drug effects / Q000528:radiation effects; D012256:Riboflavin / Q000627:therapeutic use*; D016896:Treatment Outcome; D014467:Ultraviolet Therapy; D014792:Visual Acuity / Q000187:drug effects / Q000528:radiation effects
D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin