If a 55-year-old patient struggles to read small print despite corrective lenses, which mechanism predominantly explains the limitation in their focusing ability?

💡 Explanation

Presbyopia involves the lens losing elasticity and the ciliary muscle weakening. Accommodation insufficiency occurs because the ciliary muscle cannot effectively change the lens's shape for near vision; therefore, near focus becomes difficult. This is accommodation insufficiency, rather than issues directly within the cornea, vitreous humor, or retina.

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