Topographic and biomechanical comparison of diluted alcohol and iontophoresis-assisted versus accelerated corneal crosslinking in keratoconus

PurposeTo compare the corneal biomechanical characteristics following accelerated cross-linking (A-CXL) and diluted alcohol and iontophoresis-assisted corneal cross-linking (DAI-CXL).MethodsForty-nine eyes from 41 patients who underwent DAI-CXL or A-CXL for progressive keratoconus were included. Visual acuity, topographic, and biomechanical data were analyzed preoperatively and 12 months postoperatively.ResultsA significant decrease in flat keratometry (K1) and thinnest corneal thickness (TCT) was observed in the A-CXL group between baseline and postoperatively (K1, <i>p</i> = 0.001; TCT: <i>p</i> = 0.007). Both groups showed a significant decrease in steep keratometry (K2) and maximum keratometry (Kmax) compared to baseline (K2: <i>p</i> = 0.03, <i>p</i> < 0.001, respectively; Kmax: <i>p</i> < 0.001 for both groups). Postoperatively, highest concavity time (HCT) was significantly lower (<i>p</i> = 0.007), and highest concavity peak distance (HCPD) was significantly higher (<i>p</i> = 0.034) in the DAI-CXL group compared to the A-CXL group. A significant increase in applanation 1 velocity (A1V), HCPD, and deformation amplitude (DA) (<i>p</i> = 0.03, 0.007, 0.02, respectively) and a decrease in Ambrósio relational thickness to the horizontal profile (ARTh) (<i>p</i> < 0.001) were noted in the A-CXL group at 12 months. The DAI-CXL group showed a significant decrease in HCT, integrated radius (IR), and ARTh (<i>p</i> = 0.006, 0.011, 0.009, respectively) between baseline and postoperative assessments. Corvis Biomechanical Factor (CBiF) and E-stage remained stable in both groups.ConclusionDAI-CXL and A-CXL demonstrate comparable efficacy in achieving visual, topographic, and biomechanical stabilization in progressive keratoconus over a 12-month period.