During cataract surgery, a rigid intraocular lens (IOL) replaces the natural lens. Why does this IOL lead to a loss of accommodation, affecting near and far focus?

💡 Explanation

Accommodation requires the ciliary muscle to change the lens shape, altering its refractive power. Because the rigid IOL cannot change shape, the ciliary muscle's contraction cannot adjust focus, therefore, accommodation is lost, rather than other refractive components of the eye failing.

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