Comparison of RiboflavinUltraviolet-A Cross-Linking in Porcine, Rabbit, and Human Sclera

Abstract EN

Purpose.

To compare the biomechanical properties of porcine, rabbit, and human sclera before and after riboflavin/ultraviolet-A (UVA) collagen cross-linking (CXL).

Methods.

Eight rabbits, 8 porcine eyeballs, and 8 human eyeballs were included.

One rabbit eye and half of each bisected human and porcine eyeball were treated with riboflavin/UVA CXL.

Untreated fellow rabbit eyes and eyeball halves served as controls.

A 10 mm × 20 mm scleral band was harvested from each specimen.

From this band, two 3.5 mm × 15.0 mm strips were prepared for biomechanical testing.

The biomechanical parameters were ultimate stress, stress and Young’s modulus.

Results.

Values of stress, and Young’s modulus showed that human sclera was 4 times stiffer than porcine sclera and 3 times stiffer than rabbit sclera.

In rabbit sclera, both the stress and Young’s modulus were significantly increased by CXL (P<0.05).

In porcine sclera, only the ultimate stress was significantly increased by CXL (P<0.05).

The biomechanical properties of human sclera were not statistically affected by CXL (P>0.05).

Conclusions.

Human sclera has higher biomechanical stiffness than porcine and rabbit sclera.

With the same irradiation dose, riboflavin/UVA CXL increases the biomechanical stiffness of rabbit sclera but not porcine or human sclera.