Which condition can lead to a 'cherry red' spot on the retina?

A 'cherry red' spot on the retina is most commonly associated with central retinal artery occlusion (CRAO). This condition occurs when there is a blockage of the central retinal artery, which leads to a sudden loss of blood supply to the retina.

When there is a central retinal artery occlusion, the surrounding retinal tissue becomes ischemic due to lack of blood flow and therefore appears pale. However, the fovea—a small depression in the retina responsible for sharp central vision—retains its blood supply from the choroidal circulation. This results in a distinct contrast: the pale areas surrounding a more intensely colored fovea, creating the appearance of a 'cherry red' spot.

Thus, recognizing the 'cherry red' spot is clinically significant for diagnosing CRAO and initiates urgent management to restore blood flow and prevent permanent vision loss. Understanding the pathophysiological processes that lead to this characteristic finding can help in effectively identifying and treating the underlying condition.