Farsightedness (hyperopia) is a common vision condition where people have difficulty focusing on objects up close. This refractive error occurs because the eye is too short from front to back, or the cornea is flatter than it should be. As a result, incoming light rays converge to a focal point behind the retina instead of directly on its surface. Correction involves adding optical power to shift this focal point forward, ensuring the image lands precisely on the retina for clear vision.
Non-Surgical Correction: Eyeglasses and Contact Lenses
The simplest and most widely used method to correct hyperopia involves using external convex lenses, which are thicker in the center than at the edges. These plus-powered lenses work by pre-converging light rays before they enter the eye, compensating for the eye’s insufficient focusing power. This pre-adjustment ensures the image focuses correctly on the retina, eliminating blur.
Eyeglasses offer several lens options depending on the person’s age and visual needs. Younger patients often use single-vision lenses, providing correction across the entire lens surface. As people age, typically after 40, they may also experience presbyopia, requiring multifocal lenses like bifocals, trifocals, or progressive lenses that offer a smooth transition between distance and near vision corrections.
Contact lenses provide a non-spectacle alternative and function the same way, using convex power to adjust the light path. Both soft and rigid gas permeable (RGP) contact lenses are available, including specialized multifocal designs that address both hyperopia and presbyopia.
Laser Refractive Surgery Options
For those seeking a permanent solution, laser refractive surgery modifies the shape of the cornea to change its focusing power. The two primary procedures used for hyperopia correction are Laser-Assisted In Situ Keratomileusis (LASIK) and Photorefractive Keratectomy (PRK). Unlike the procedure for nearsightedness, correcting hyperopia requires the surgeon to steepen the central cornea.
The excimer laser achieves this steepening by using an annular ablation pattern, which removes more tissue from the mid-periphery of the cornea than from the center. This differential removal causes the central cornea to bulge slightly forward, increasing its refractive power and moving the light’s focal point onto the retina. This technique is most effective for low to moderate hyperopia, up to +5.00 diopters (D).
LASIK involves creating a thin flap in the cornea before applying the laser, allowing for a faster visual recovery and less postoperative discomfort. PRK, a surface-based procedure, removes the outermost layer of corneal cells entirely before laser application, leading to a longer, more uncomfortable healing period as the epithelial layer regrows. However, PRK may be a preferred option for individuals with thinner corneas who are not suitable candidates for LASIK.
Intraocular Lens Procedures
When hyperopia is too severe (above +4.00 D) or when corneal laser surgery is unsuitable, a surgeon may recommend placing a lens inside the eye. These intraocular lens (IOL) procedures include Refractive Lens Exchange (RLE) and the implantation of Phakic Intraocular Lenses (pIOLs).
RLE, which is nearly identical to cataract surgery, involves removing the eye’s clear natural lens and replacing it with a synthetic IOL customized for the patient’s hyperopic prescription. This procedure is frequently recommended for older patients, typically over age 40 or 50, because it simultaneously corrects hyperopia and eliminates the possibility of future cataracts.
A Phakic IOL is a different approach, where a corrective lens is implanted without removing the natural lens. This method is often the preferred choice for younger adults with high hyperopia because it preserves the natural lens and the eye’s ability to change focus. Phakic IOLs are placed either in the anterior chamber or the posterior chamber. Both RLE and pIOL implantation offer a stable and predictable correction, often providing better quality of vision for high prescriptions than corneal laser procedures.
Factors Influencing Treatment Selection
The choice among external lenses, corneal laser surgery, and IOL procedures depends on individual factors. The severity of the hyperopia is a primary determinant; lower prescriptions are well-suited for glasses, contacts, or LASIK, while higher powers often require the stability and greater corrective range of an IOL procedure. A patient’s age is also a major consideration, particularly regarding presbyopia and the accommodation capacity of the natural lens. Surgical options are further limited by anatomical factors, such as the thickness and curvature of the cornea, which must be healthy enough to undergo laser reshaping. Lifestyle, occupational needs, cost, recovery time, and willingness to accept surgical risks all contribute to the final, personalized treatment recommendation.