What is the term for the loss of the crystalline lens's ability to accommodate?

The term for the loss of the crystalline lens's ability to accommodate is presbyopia. This condition typically occurs as a natural part of aging, often starting in the early to mid-forties. The crystalline lens becomes less flexible over time, making it difficult for individuals to focus on close objects, leading to symptoms like blurred vision when reading or doing other close work.

Myopia refers to nearsightedness, a refractive error where distant objects appear blurry while close objects can be seen clearly, but it doesn't relate to the flexibility of the lens. Hyperopia, or farsightedness, is a condition where distant objects may be seen more clearly than nearby objects, and it also doesn't involve the loss of accommodation due to lens flexibility. Astigmatism is a refractive error caused by an irregular shape of the cornea or lens, leading to distorted or blurred vision, but it does not pertain to the loss of the lens's ability to change shape for focusing.

Understanding presbyopia is crucial for recognizing changes in vision as one ages, and it emphasizes the importance of regular eye examinations to adapt vision correction needs accordingly.