Today’s IOL technologies allow cataract patients to tailor their vision to their individual needs. With tools like InSightVR that let patients experience how different lenses may affect their vision, this guide explains the benefits and trade-offs of each option so you and your doctor can choose the best fit.
Monofocal Lens
A monofocal intraocular lens (IOL) is the most traditional type of lens replacement. It is designed to provide sharp focus at a single, predetermined distance. While most people choose to correct for best distance vision, some may opt for clear near vision instead. Depending on the amount of astigmatism present, patients may require glasses for their best vision at all distances.
- Primary Benefit: remove the cataract to restore vision quality
- Focal point options:
- Myopic: Patients that wish to remain nearsighted after cataract surgery can be targeted for a myopic target and continue to take glasses off to read at the end of the day as they wish.
- Plano: Most commonly, patients choose to target for best distance vision; depending on the amount of astigmatism present on the cornea, patients may be able to see well enough without glasses if comfortable.
- Monovision: targeting one eye for near and the second for distance vision allows for a blended vision and the potential for lessened dependency on glasses. Patients typically trial with contact lenses prior to surgery to determine success with brain adaptation.
- Procedure: It is a traditional, time-tested option for cataract surgery.
Astigmatism-Correcting Lens (Toric)
A Toric IOL is a premium monofocal lens designed specifically for patients with corneal astigmatism, a condition where the cornea is irregularly shaped, this impacts the far majority of the population. The lens has different powers in different meridians, which helps to neutralize the uneven curvature of the cornea.
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- Primary Benefit: Corrects both the cataract and the astigmatism, resulting in improved uncorrected distance vision.
- Focal point: Like a standard monofocal lens, it is typically set for one focal point, meaning glasses are usually required for intermediate (computer) and near (reading) tasks.
- Ideal candidate: patients that are hoping for independence from glasses/contact lenses for distance activities, but are happy to reach for a pair of glasses for near work
Multifocal Lens
A multifocal IOL works like a bifocal or trifocal pair of glasses, having multiple rings or zones of power built into the lens. These different zones allow the eye to focus light from various distances (near, intermediate, and far) simultaneously. The brain learns to select the correct focus automatically.
- Primary Benefit: Significant reduction in or elimination of the need for glasses for most daily activities, offering spectacle independence.
- Education Opportunity: patients may experience visual disturbances such as halos or glare around lights, especially at night, which can diminish over time. There may also be a slight compromise in contrast sensitivity.
Ideal Candidate: Best suited for patients who prioritize being able to see at multiple distances without glasses.
Extended Depth of Focus (EDOF) Lens
EDOF lenses utilize a single, elongated focal point rather than multiple distinct focal points. This stretched focus provides a continuous range of clear vision, primarily from a functional distance out to far distance, with less noticeable visual compromises than some multifocal designs.
- Primary Benefit: Provides a strong range of continuous vision, often covering distance and intermediate tasks (like computer work), while typically having a lower incidence of halos and glare compared to traditional multifocal IOLs.
- Education Opportunity: While offering a great intermediate range, the near vision may not be as sharp as the near vision provided by a dedicated multifocal lens, patients may need reading glasses for fine print.
- Design: The design focuses on merging the far and intermediate focal points to create a smooth, extended zone of clarity.
Monovision
Monovision is a vision correction strategy, not a specific type of lens. It can be achieved with any standard monofocal IOL. The concept relies on the brain adapting to use the distance-corrected eye for tasks far away and the near-corrected eye for reading.
- Primary Benefit: Achieves a functional range of vision without the rings or zones found in multifocal lenses, thus avoiding potential side effects like glare and halos.
- Trade-off: It may result in a slight loss of depth perception, particularly in dim lighting, and some individuals cannot adapt to the difference between the two eyes. A trial with contact lenses is often recommended before surgery.
- Strategy: This approach is a common solution for patients who are good candidates for monofocal IOLs but want to minimize their reliance on reading glasses.
Choosing the right IOL is an important part of achieving your best possible vision after cataract surgery. If you have questions or want help understanding your options with InSightVR, contact us to learn more.