Final answer:
LASIK procedure adjusts the power of a myopic patient's eye by altering the cornea. The range of diopters for spectacle lenses needed after LASIK with a ±5.0% uncertainty is from 8.55 D to 9.45 D. The patient was nearsighted before LASIK, as distant vision correction requires a reduction in the eye's power.
Step-by-step explanation:
Vision Correction and LASIK Procedure
When a myopic patient undergoes a LASIK procedure, the goal is to correct their vision by changing the power of their eye. In this case, the power was reduced by 9.00 D. With a ±5.0% uncertainty in the final correction after the LASIK procedure, we can calculate the range of diopters needed for clear prescription lenses. The range can be found by multiplying 9.00 D by 5%, which gives us a variation of ±0.45 D. Therefore, the patient may need spectacle lenses within the range of 8.55 D to 9.45 D.
The person was nearsighted, or myopic, before the procedure, as is evident from the need to reduce the power of the eye. Nearsightedness means the eye has too much focusing power, causing distant objects to appear blurry, so reducing the power is necessary for correction.
If the LASIK correction introduces a fixed percent uncertainty, individuals with greater corrections have a higher absolute range of uncertainty. This could result in a poorer chance of achieving normal distant vision because the room for error is larger.
Concerning presbyopia, even if LASIK corrects for distant vision, the patient may still need reading glasses because presbyopia affects close vision, indicating that separate correction might be necessary for reading or seeing objects at a close distance.
In the case of intraocular lenses for cataract patients, while they can provide clear prescription for distant vision, reading glasses might still be required due to the fixed focusing power of these lenses, lacking the accommodation ability of a natural lens.