Tomographic and biomechanical corneal characteristics of patients with angioid streaks

To evaluate the corneal biomechanical properties in patients with angioid streaks (AS), and to compare these parameters with those of healthy subjects.

A retrospective study was conducted, enrolling AS patients and healthy participants as controls. The collected corneal tomographic parameters included flat keratometry, steep keratometry, mean keratometry, maximum keratometry, topographic cylinder value, central corneal thickness, and the total deviation value of the Belin-Ambrósio enhanced ectasia display measured with Pentacam tomography. Corvis ST was used to measure corneal biomechanical parameters, non-contact tonometry intraocular pressure (IOPnct), and biomechanically corrected intraocular pressure (bIOP).

The study comprised 18 eyes from 10 male and 8 female AS patients with a mean age of 48.83±10.66y, and the controls included 31 eyes from 12 male and 19 female healthy participants with a mean age of 47.87±10.69y. All corneal tomographic parameters were comparable between the two groups (all P>0.05), and no corneal ectasia was observed in any AS patient. Compared with the controls, AS patients exhibited statistically significant increases in applanation 1 (A1) time and stiffness parameter A1 (SP-A1), along with significant decreases in applanation 2 (A2) velocity, deformation amplitude (DA), DA ratio (2 mm), and Corvis biomechanical index (CBI; all P<0.05), which indicated higher corneal stiffness in AS. The IOPnct value in AS was significantly elevated, while no significant difference was found in the bIOP value compared to controls (P=0.031 and P=0.095, respectively).

Eyes with AS exhibit normal corneal tomographic characteristics and increased corneal stiffness.