Imaging may be referred to as the ‘eyes of science’ as it provides scientists with highly informative multi-dimensional and multi-parameter data usually invisible to the naked eye. As instrumentation technologies and genetic engineering advances, it’s possible in modern times to observe and image highly dynamic biochemistry processes. This paper reviews PET (Positron Emission Tomography), MRS (Magnetic Resonance Spectroscopy), MRI (Magnetic Resonance Imaging), CT(Computed Tomography), Ultrasound, Visible light microscopy, BLI (Bioluminescence) and FMT (Fluorescence Mediated Tomography) imaging techniques, highlighting the principles behind the operation of each technique, their major strengths and drawbacks. With the enhancement of the existing techniques and evolution of new ones, the future possibility of refined view of systems invisible to naked human eye is promising. More so is when two or more techniques are combined in biological systems analysis.
Keywords: Optical, Imaging, Microscopy, Resolution, Fluorescence