When fitting contact lenses, what is a crucial step to ensuring patient comfort?

Choosing the correct diameter of the contact lens is essential for patient comfort because the diameter affects how well the lens aligns with the surface of the eye. A lens that is too small may not provide adequate coverage, leading to discomfort, while a lens that is too large can cause excessive movement, irritation, or even potential damage to the corneal surface during blinking.

Proper diameter selection ensures that the lens sits comfortably and securely on the eye, allowing for normal eyelid movement without causing friction. This can enhance the overall stability of the lens during wear, thereby contributing to a better vision experience and minimizing any sensations of irritation or foreign body sensation. Moreover, a well-fitted lens diameter can also help in maintaining moisture levels, as it can affect how tears interact with the lens, which is critical for comfort over extended wear periods.

While previous lens history, lens tightness, and fitting over corneal irregularities are important considerations in fitting lenses, they do not directly address the foundational elements of comfort in the same way that selecting the appropriate diameter does.