Transepithelial iontophoresis corneal collagen cross-linking for progressive keratoconus: initial clinical outcomes.
OBJECTIVE
To report initial clinical results of transepithelial corneal collagen cross-linking with iontophoresis (I-CXL).


METHODS
Twenty eyes of 20 patients diagnosed as having progressive keratoconus who underwent I-CXL were included in this prospective non-randomized clinical study. Corrected distance visual acuity (CDVA), spherical equivalent and cylinder refraction, various corneal topography and Scheimpflug tomography parameters, aberrometry, anterior segment optical coherence tomography, and endothelial cell count were assessed at baseline and at 1, 3, 6, and 12 months postoperatively.


RESULTS
CDVA improved significantly at 3, 6, and 12 months postoperatively (logMAR difference of -0.07 ± 0.01, -0.09 ± 0.03, and -0.12 ± 0.06, respectively; P < .05). Aberrometry remained stable during follow-up and a trend toward improvement was noted. All topographic parameters (including maximum keratometry) were stable during the follow-up, but exhibited a positive non-significant trend toward improvement. Minimum corneal thickness values were stable for up to 12 months postoperatively. None of the patients showed a progression of keratoconus. Endothelial cell counts did not change significantly (P > .05).


CONCLUSIONS
Preliminary results up to 1 year postoperatively indicate the efficacy of I-CXL in stabilizing the progression of this degenerative disease combined with significant improvement of CDVA. I-CXL, which spares the corneal epithelium, has the potential to become a valid alternative for halting the progression of keratoconus while reducing postoperative patient pain, risk of infection, and treatment time in select patients; however, the relative efficacy of this technique compared to standard epithelium-off techniques remains to be determined.
Paolo
P
Vinciguerra
J Bradley
JB
Randleman
Vito
V
Romano
Emanuela F
EF
Legrottaglie
Pietro
P
Rosetta
Fabrizio I
FI
Camesasca
Raffaele
R
Piscopo
Claudio
C
Azzolini
Riccardo
R
Vinciguerra
D000328:Adult; D000869:Anterior Eye Segment / Q000473:pathology; D002452:Cell Count; D003094:Collagen / Q000378:metabolism*; D003319:Corneal Stroma / Q000378:metabolism*; D019781:Corneal Topography; D003432:Cross-Linking Reagents / Q000627:therapeutic use*; D004728:Endothelium, Corneal / Q000473:pathology; D019573:Epithelium, Corneal; D005260:Female; D006801:Humans; D007478:Iontophoresis / Q000379:methods*; D007640:Keratoconus / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D017319:Photosensitizing Agents / Q000627:therapeutic use; D011446:Prospective Studies; D012256:Riboflavin / Q000627:therapeutic use; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology
D003432:Cross-Linking Reagents; D017319:Photosensitizing Agents; D003094:Collagen; D012256:Riboflavin