The vitreous is at the root cause of numerous retinal conditions, including retinal detachment, macular hole, vitreomacular traction and epiretinal membrane. The advent of optical coherence tomography has dramatically increased our understanding of the pathogenesis of these conditions and helped to improve surgical management.
The vitreous fills the space in the eye between the lens and retina, occupying 80% of the internal volume of the globe. It is a transparent, avascular and mostly acellular gel consisting of 99% water, proteins, glycosaminoglycans and small amounts of salts and metabolites.1 It has a denser cortex and more liquid centre. The anterior part of the vitreous is permanently attached to a 4 to 6 mm annulus of retina and ciliary body, and is termed the vitreous base (Figure 1a). Posteriorly, the vitreous is relatively loosely attached, but the adhesion is firmer at the optic disc, at the macula, along blood vessels and over abnormal retinal lesions such as lattice degeneration.2 This is a key concept in understanding the pathogenesis of vitreoretinal interface disorders.