The response of porcine eyes to air puff at well controlled levels of intraocular pressure (IOP) was visualized and quantified using air-puff combined with Swept-Source OCT instrument. The viscoelastic properties of the corneas of model animals appeared as a hysteresis of the deformation amplitude vs. applied air pressure. The corneal apex displacement amplitude was strongly correlated to the hysteresis loop area. The cornea became stiffer after CXL treatment but the parameters were statistically significant for higher levels of IOP.