Optical treatment
Presbyopia can be corrected either optically or surgically. Optically, bifocal and progressive eyeglasses can be prescribed. The latter are spectacles with central correction designed for the far, and then from the center to the inferior periphery, there is an increase in convexity (increase in positive power of the lenses) so they correct the near. This is based on the principle that people usually look down to read at near (newspaper, smartphones), and somehow less (obliquely down) for intermediate (computers), and straight for far (with exceptions, for which the eyeglasses can be tweaked accordingly). Multifocal contact lenses might also be an option in some patients.
Surgical treatment options
Surgically, presbyopia can be corrected using a variety of options, based on the patient's exam, lifestyle, and needs. Monovision LASIK monovision (full or partial): in this procedure, one eye is corrected for distance, and the other for near vision. With both eyes open, the patient sees both for far and for near. The advantages of monovision LASIK is that it is a quick and well-established procedure, and it works for some people with good brain adaptability. The main downsides are reduced depth perception and suboptimal uncorrected night vision. Other options include laser blended vision, a procedure performed in combination with Femto-LASIK. Instead of correcting one eye for near and one for distance, laser blended vision reshapes both corneas, with only a micro-monovision in the non-dominant eye, with an improvement of depth of focus of the eye's optics, to create a seamless transition from far to near vision. It preserves binocular depth perception and is more natural for the brain to adapt to. Popular laser blended vision procedures are PresbyMAX and PresbyOND. It is important to note that some patients might need a minor enhancement over time. Another option is Lens exchange. In this procedure, the eye’s natural lens is replaced with an artificial intraocular lens (IOL) to restore vision at multiple distances. For patients without cataracts, it is known as Clear Lens Exchange (CLE) or refractive Lens Exchange (RLE), and is an elective procedure that removes the aging natural lens and replaces it with a multifocal intraocular lens or an extended-depth of focus lens (EDOF IOL). For patients with early or advanced cataracts, this becomes a cataract surgery with premium IOL, and is the ideal solution to treat the clouded lens, far vision, and presbyopia. Advantages of the Clear Lens Exchange and cataract surgery with premium IOL is that they are a permanent solution, and are ideal for patients with early lens aging or cataracts. The only downsides is that they involve surgery inside the eye, and might cause halos around lights or glare in some low lighting conditions, although the majority of patients tend to adapt to them with time. Additionally, they are not recommended in patients with retinal or corneal diseases.
