OPTICAL COHERENCE TOMOGRAPHY IN ONCOLOGICAL IMAGING

The Optical Coherence Tomography (OCT) is an emerging imaging technique with applications in medicine and biomedical optics. OCT is capable of analyzing internal localized microstructures and obtaining high-resolution cross-sectional images by backscattered light echo analyze. With resolutions of 1-15 mu m, one or two orders of magnitude finer than conventional ultrasound, the OCT is improving the small body imaging techniques. The OCT is mostly a near infrared based analysis technique. The design of OCT systems is based on a Michelson interferometer coupled with a low coherence light source. One arm of the interferometer emits a directed beam scanning the sample. OCT imaging engines usually employ time domain detection using a reference delay arm in order to perform the interferometry. The development of high speed diffraction grating scanners enabled OCT systems to achieve imaging speeds of several thousand axial scans per second and also video rate imaging. A generic OCT system uses a circulator to collect phase interference signals. By subtracting the signals, the desired interference signal adds and excess noise from the light source gets cancelled. This configuration is nominated as dual balanced detection and is used in coherent optical communications systems. Considering its ability to in vivo analyze and its capacity to obtaining cross-sectional images, the OCT system can be implemented as a tool used to improve the surgical gesture during tumor removal surgeries. In order to obtain the best results, the OCT needs to be improved with a simple spectroscopic device.