The Vivity lens is an Extended Depth of Focus (EDOF) intraocular lens used during cataract surgery to replace the eye’s natural lens. Unlike traditional lenses that focus at a single point, the Vivity is designed to provide a continuous range of vision from distance to arm’s length. While it represents a significant advance in vision correction, no artificial lens is considered perfect, and patients occasionally report specific visual challenges. Understanding these common complaints and their management is important for setting appropriate expectations and achieving a positive outcome.
Common Visual Disturbances (Dysphotopsia)
The most frequent visual complaints with advanced intraocular lenses are phenomena collectively known as dysphotopsia, which involves unwanted light effects. For the Vivity lens, these often manifest as mild halos, glare, or starbursts, particularly when looking at light sources at night. These light anomalies occur because the lens uses a proprietary non-diffractive design called X-Wave technology to extend the focus of light.
This wavefront-shaping method works by subtly stretching and shifting the light that passes through the lens to create an elongated focal point rather than splitting it into multiple distinct points. Because the light is not split, the incidence and intensity of halos and glare are generally much lower compared to older, diffractive multifocal lenses. Despite the low reported rates, these effects can still be noticeable, especially when driving at night.
A related complaint is a subtle reduction in contrast sensitivity, particularly in low-light conditions. This decrease is a known trade-off for the extended range of focus, affecting the ability to distinguish objects from their background. Patients may perceive this as difficulty discerning details in shadows or during periods of dim illumination. These visual artifacts are a function of the lens’s specialized optics, which prioritizes a broad range of vision.
Limitations in Near Vision Performance
A significant point of patient dissatisfaction arises from the functional limits of the Vivity lens, especially concerning close-up tasks. The lens is highly effective at providing clear distance and intermediate vision, which is ideal for driving and computer use. However, the design compromise means the lens does not deliver the sharp, high-powered near focus of a true multifocal lens.
Patients typically find that while they can read a cell phone screen or a menu without glasses, they may struggle with fine print, such as prescription labels or prolonged book reading. Many patients still require low-powered reading glasses for these very close or sustained activities. The need for glasses for fine print is not a lens defect but an inherent characteristic of its EDOF technology, which sacrifices some near acuity to minimize visual disturbances.
This limitation means the Vivity lens reduces spectacle dependence, but it rarely achieves complete spectacle independence for all tasks. Patients whose primary goal is to never wear glasses for reading small text may find the lens’s near vision performance disappointing. The functional vision provided is best described as “arm’s length” or intermediate, not the sharp, up-close vision a dedicated multifocal lens provides.
Factors Contributing to Patient Dissatisfaction
Not all complaints are directly caused by the lens’s design; many stem from factors related to the patient experience and surgical outcome. These factors can amplify visual complaints or mimic lens-related issues:
- Unrealistic expectations: Patients expecting complete freedom from glasses for all distances may be disappointed by the need for reading aids, often due to insufficient pre-operative counseling.
- Residual refractive error: A slight mismatch between the implanted lens power and the eye’s final needs, such as uncorrected astigmatism or deviation from the target focus, can significantly reduce vision quality and amplify the perception of halos or blur.
- Ocular surface disease: Conditions like dry eye compromise the tear film, scattering light and reducing visual quality, which patients may mistakenly attribute to the lens itself.
- Post-surgical issues: Posterior capsule opacification (PCO), also known as a secondary cataract, can cloud vision and lead to complaints of blur or glare that require separate treatment.
Management and Resolution of Complaints
The primary resolution for most mild visual disturbances is a process called neuroadaptation, where the brain gradually learns to filter out the new visual signals. For Vivity patients, the brain adjusts to the extended depth of focus and minimizes the perception of artifacts like glare over a period of weeks to months. Most patients find that the halos and starbursts become less bothersome as their visual system adapts.
Medical management is often employed to address underlying causes that exacerbate visual issues. Treating dry eye with lubricating drops or anti-inflammatory medication can stabilize the tear film, improving overall optical quality. For patients with persistent night vision issues, doctors may prescribe specific eye drops, such as alpha-2 agonists, to temporarily reduce pupil size, thereby limiting the light-scattering effect of the lens’s edge in low light.
If a small residual refractive error is present, a minor enhancement procedure, like a laser vision correction, can refine the focus and optimize the lens’s performance. If neuroadaptation fails and dissatisfaction remains severe, an intraocular lens exchange is considered as a last resort, involving surgical removal of the Vivity lens and replacement with a different type, typically a standard monofocal lens.