What is the purpose of a trial lens in fitting?

The purpose of a trial lens in fitting is primarily to evaluate the patient's comfort and vision with a specific lens type before prescribing. This practice allows the practitioner to assess how well the lens fits on the eye, how it feels to the patient, and whether it provides adequate visual acuity. By using trial lenses, the practitioner can ensure that the chosen lens will meet the patient's needs for comfort and vision, leading to a better overall fit and satisfaction once the permanent lenses are prescribed.

Trial lenses allow for real-time feedback from the patient, which is essential for fine-tuning the parameters of the lens, such as curvature, diameter, or prescription strength, to achieve optimal results. This process is crucial in establishing a successful contact lens fitting, helping to avoid potential discomfort or visual issues that could arise if lenses were prescribed without prior testing.

Although the aesthetic match of the lens, durability testing, and comparison of brands are important considerations in the contact lens fitting process, they do not represent the primary purpose of using a trial lens. The main focus is on ensuring the patient can wear the lenses comfortably and effectively before finalizing their prescription.