Senescence of the eyes is often demonstrated by the presence of

Senescent cells

The Senescence of the eyes is often demonstrated by the presence of senescence cells. They are forms of cells that are normally capable of replication within mammalian tissues but permanently non-dividing and share features with oncogene-induced senescence. Moreover, the accumulation of senescent cells has been overwhelmingly studied using fibroblasts and has been proposed to act as an ageing mechanism. 

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