Methodologies on the Enhanced Spatial Resolution of Non-Invasive Optical Brain Imaging: A Review

Optical brain imaging (OBI) has the potential for a bright future thanks to its low cost and portability relative to other biomedical imaging modalities. Temporal and spatial resolutions are considered to be the discriminatory features for selection of biomedical imaging equipment. OBI systems, however, still face the bottleneck of limited spatial resolution. In this study, existing methodologies and designs for enhancement of spatial resolution of OBI are comprehensively summarized. This is the first study reviewing all such techniques, therefore, is beneficial for researchers working in this field. The study presents general overview of principle of OBI followed by pros and cons specifically the challenges in enhancement of spatial resolution. Later, different novel existing methodologies, algorithms design and configurations, phantom related studies presenting spatial resolution enhancement have been discussed. Finally, conclusion and future directions are presented with an idea to enhance the spatial resolution of OBI up to nanoscale.