Label-free and non-invasive detection of ultrastructural morphology, classification of different types of spheroids and tissues, interaction of biomaterials with tissues, and osseointegration of living bones with implants at different stages, using nanosensitive optical coherence tomography (nsOCT) technique, are beneficial for the treatment planning in oncology, cardiology, dentistry and surgery, without the need for invasive biopsy procedures, requirement of contrast agents or ionizing radiation. In this work, OCT images were acquired from different ex vivo bovine biological tissues such as bone, muscle, fat, and skin using the SD-OCT system (GAN 611C1, Thorlabs), with a 930 nm superluminescent light emitting diode, with a bandwidth of 102 nm, and an axial resolution of 5.5 μm. Compared to a conventional OCT system which provides up to 1 μm axial resolution with a broadband supercontinuum laser source, nsOCT aids in the enhancement of axial resolution to nanoscale order. The characterization of spatial periods between 291 nm and 342 nm, for the wavelength range of 874 nm to 1027 nm, has been possible for different bovine tissues. A difference in the structural patterns in terms of spatial periods was observed between the hard and soft tissues. A definite nanostructural pattern was observed for hard tissues like the bone and burnt skin, whereas, soft tissues, fat, and muscle had an irregular pattern. This work can be further extended towards automated sub-micron level differentiation of healthy and malignant tissues, and also for bone-tissue engineering applications, using Deep Learning algorithms.
|