Optical clearing is an effective method to reduce light scattering of biological tissues that provides significant enhancement of light penetration into the biological tissues making non-invasive diagnosis more feasible. In current report Optical Coherence Tomography (OCT) in conjunction with optical clearing is applied for assessment of deep cartilage layers and cartilage-bone interface. The solution of Iohexol in water has been used as an optical clearing agent. The cartilage-bone boundary becomes visible after 15 min of optical clearing that enabling non-invasive estimation of its roughness: Sa = 10 ± 1 μm. The results show that for 0.9 mm thick cartilage optical clearing is stopped after 50 min with an increase of refractive index from 1.386 ± 0.008 to 1.510 ± 0.009. Current approach enables more reliable detection of arthroscopically inaccessible regions, including cartilage-bone boundary and subchondral bone, and potentially improves accuracy of the osteoarthritis diagnosis.
- Articular cartilage
- Optical clearing
- Optical Coherence Tomography (OCT)
- Subchondral bone