Quantifying contact lens-related changes in keratoconus corneal topographic indices: an updated Pentacam Scheimpflug imaging analysis.

Slowing ectasia progression is critical for maintaining visual potential in keratoconus (KC), for which various therapeutic approaches have been implemented. A Pentacam Scheimpflug imaging device was used to quantify contact lens (CL)-related changes in keratoconus corneal topographic indices. Thirty KC patients (group 1; 60 eyes) were using one of the three CL (rigid gas-permeable CL (RGPCL)-10, hybrid CL (HCL)-10, and scleral CL (SCL)-10 patients). A control group included 30 KC patients (group 2; 60 eyes) not using CLs due to intolerance or inappropriateness. The Pentacam® HR Scheimpflug imaging device was used to measure topographic indices such as Km anterior, Km posterior, K max, corneal thickness (CT, corneal central, apex, and thinnest), corneal volume (CV), anterior chamber volume (ACV), and anterior chamber depth (ACD) at baseline, 3rd, 6th, and 12th months. The mean ages for groups 1 and 2 were 32±10 and 31±09 years, respectively. Group 1 had a lower but statistically significant change in K max than group 2 (<0.038). Also, group 1 had a minor but non-significant decrease in anterior and posterior keratometry values compared to group 2 (pKm ant. right/ left eye = 0.063/ 0.065 and 0.087/ 0.094, respectively). RGPCL users had significant changes in central CT, thinnest CT and ACD (<0.041). SCL users had more stable changes than other CLs for the thinnest CT along with significant changes in K max, pachy apex and ACV (<0.036). HCL users had significantly higher K max stability (<0.039). Regular use of appropriate therapeutic CLs may help to stabilize corneal deformity, thereby slowing changes in corneal topographic indices in KC.