Advances in the Surgical Correction of Presbyopia

George O. Waring IV, MD; Duncan E. Berry, BA

Disclosures

Int Ophthalmol Clin. 2013;53(1):129-152. 

In This Article

Presbylasik

Technique and Theory

The idea that corneal multifocality could be achieved by excimer laser ablation is rooted, to a large degree, in the positive corneal aberrations observed in early photorefractive kerectomy patients.[49] Because LASIK is a more controllable technique for corneal multifocality, it is developing as yet another option for the surgical treatment of presbyopia. Three different approaches have been used for creating corneal multifocality using LASIK—transitional multifocality, central presbyLASIK, and peripheral presbyLASIK.[50] Only the latter 2 techniques will be discussed here because of the fact that transitional multifocality has been largely abandoned.[50] On a theoretical level, peripheral and central presbyLASIK differ in the principles upon which each technique is based. Peripheral presbyLASIK depends upon increasing the range of pseudoaccommodation whereas central presbyLASIK essentially creates a bifocal.[50]

In peripheral presbyLASIK, the peripheral cornea is ablated so as to create a negative peripheral asphericity which in turn increases the depth of focus. Thus, the center of the cornea is left for distance, whereas the peripheral cornea is for near. Central presbyLASIK, on the other hand, involves creation of a hyperpositive area for near vision in the central cornea, resulting in a surface which functions in a similar manner to the diffractive multifocal IOLs discussed previously.[50] Several ablation profiles have been created for these techniques, the specifics of which will not be addressed in this article.

Efficacy

For peripheral presbyLASIK, the largest published study included 296 eyes and demonstrated that binocularly, 98% of patients achieved UDVA of 20/20 or better and 100% achieved 20/32 or better; 96% achieved UCNVA of J2 and 99% could read J3 or better.[51] Several other studies have demonstrated similar findings.[52–54] For central presbyLASIK, the results of UCVA are in between 0.8 and 1.0 for distance vision and J2 for near vision in the majority of patients.[50]

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