TABLE 2.
A summary of characterization techniques used to evaluate decellularized corneal scaffolds.
| Mechanical techniques | Application | Advantages | Disadvantages |
|---|---|---|---|
| Compression testing Stammen et al. (2001) | The tissue is placed under two plates and compressed | It can measure the mechanical behavior of the tissue and ductile fracture limits of the tissue | It flattens the tissue and damages the structural architecture |
| The test is used to determine the mechanical behavior of the tissue under the crushing load | It also gives you a detailed assessment of the tissue’s load-bearing capacity and elasticity properties | Due to the corneal curvature shape, the test may not distribute the pressure equally | |
| Holographic interferometry Calkins et al. (1981) | Is a tool that uses a laser to trace the changes in the tissue and perform interferometric measurements | It is a precise method that can detect residual stresses and cracks on the tissue without mechanical contact | There is no fixed distance so the location of the structure cannot be obtained |
| Bulge and inflation testing Stammen et al. (2001) | Is a tool that is used to biomechanical test corneal tissue by inflating the tissue and measuring the displacement | It is a reliable tool that demonstrates the intrinsic properties of the cornea layers and resembles Intraocular pressure | The inflation capacity is difficult to control and it could affect viscoelasticity |
| Corvis STL Tonometer/Pachymeter Wang et al. (2022c) | Corvis ST is a device that uses a high-speed Scheimpflug camera to record the cornea movement | Corvis ST device evaluates the central cornea thickness, corneal stiffness, and intraocular pressure | Very expensive |
| Ultrasound | It is a device that uses sound waves to get a very detailed image of structures | It is a non-invasive technique that shows detailed surface imaging of the cornea | It depends on the user’s skill |
| Ocular Response Analyzer Kaushik and Pandav (2012) | Is a non-invasive device that uses rapid air pulse to make an indentation in the cornea | It measures the cornea biomechanical properties such as corneal hysteresis, intraocular pressure, and corneal resistance factor | Very expensive |
| Indentation testing Wilson et al. (2013) | Is a test that measures the indentation left behind in the cornea after it was compressed | Determine the hardness of the cornea with minimal destruction | Doesn’t assess tensile strength |