What does the term 'transposition' refer to in eye care?

The term 'transposition' in eye care specifically refers to the process of changing the measurement of a cylindrical lens from plus to minus or vice versa, while keeping the overall refractive power the same. This is essential for accurately prescribing lenses for patients with astigmatism. During transposition, the values of the sphere, cylinder, and axis are adjusted so that the optical effect remains unchanged, which is crucial for ensuring that the patient receives the correct prescription to enhance their visual acuity. This technique allows for a clearer understanding and representation of a patient’s prescription, helping optometrists and technicians communicate effectively with other eye care professionals or when ordering lenses.

The other options do not accurately capture what transposition entails. Switching the roles of the eyes does not relate to lens prescriptions or optics, adjusting lens curvature pertains to different vision types but does not involve the transposition of cylindrical values, and changing lens color is more about visual comfort or contrast enhancement rather than a refractive manipulation.