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An understanding of the histology of the retina is essential to consider for complete insight into diseases involving a vital sensory component in the eye. The complexity of the retina, from its precise multi-layered structure to its various cell types and function, will be discussed briefly in this overview. Also, understanding features involving both structure and function will help appreciate the pathophysiology of disorders affecting the retina. Acknowledging the elements in this article may help guide future investigations towards specific therapeutic targets to help prevent, preserve, and treat irreversible vision loss.

Diseases of the retina divide into two categories, those involving the death of photoreceptors (rods and cones) at the outer nuclear layer and those involving cells in the inner retina such as the bipolar and ganglion cells. Diseases of the photoreceptors (rods and cones) are characterizable by their pattern of cellular and visual loss. Retinitis pigmentosa - rods affected first, then cones; peripheral vision loss precedes central loss Leber’s congenital amaurosis - rods affected first, then cones OR both rods and cones; peripheral vision loss precedes central loss Macular degeneration - RPE (retinal pigment epithelium), cones, & rods affected; central vision loss precedes peripheral loss Stargardt disease - RPE, cones, & rods affected; central vision loss precedes peripheral loss Cone-rod dystrophy - cones affected first, then rods; peripheral vision loss precedes central loss Retinoschisis - rods, cones, & bipolar cells affected; both central and peripheral vision loss Congenital stationary night blindness - affects the connection between photoreceptors & bipolar cells, uniform vision loss Diseases of the inner retina: Glaucoma - ganglion cells involved; peripheral vision loss Optic nerve neuropathy - ganglion cells involved; uniform vision loss When viewed using histological methods, retinal pathology can appear structurally disorganized. For example, rosette-like structures can present in diseases of the retina, including retinitis pigmentosa, diabetic retinopathy, and retinoblastoma.[1]