ABSTRACT
Scanning laser ophthalmoscope (SLO) and confocal scanning laser ophthalmoscope (cSLO) systems have very sharp and focused light sources that enhance contrast and detail and suppress out-of-focus light. These light sources and the versatility of these instruments make them excellent diagnostic tools. They also suppress noise and can be combined with other modalities, like optical coherence tomography. An SLO works by projecting a low-powered slit beam of light onto a series of vertical and horizontal vertical scanning mirrors that sweep across the retina. Light then exits the pupil and is collected by a photomultiplier tube. The slit of light is synchronized with a digital sensor; the image is saved to a computer and then displayed on a monitor. Assessing the quality of an SLO image is no different than assessing the quality of a fundus camera image. There are three basic factors to consider when evaluating a fundus image: evenness of illumination, saturation and focus.
