What exactly is cataract?
Cataract is one of the most common ophthalmic conditions, which manifests with aging (age-related cataract). Cataract is the clouding of the natural crystalline lens of the eye located behind the iris. Through this lens, which is normally transparent, light rays pass to be eventually directed to the retina. Over the years, the crystalline lens loses its original composition, clarity, and becomes cloudy, causing vision blurring.
The average age range where cataracts significantly affect vision is between 65 and 75 years, although it doesn’t mean that it cannot appear earlier or later. In rare cases, clouding of the natural crystalline lens may occur from a young age (pediatric cataract).
What are the main symptoms of cataract?
The most common symptoms that appear with cataract and affect patients’ daily activities include:
- cloudy and blurry vision
- reduced color perception (fading)
- decreased contrast sensitivity
- glare or reflections around objects
How is cataract treated?
The only effective treatment for cataract is surgical intervention, with the most prevalent and successful technique being phacoemulsification with ultrasound, performed without general anesthesia.
During the procedure, the cloudy crystalline lens (natural lens) of the eye is fragmented (destroyed), aspirated, and replaced by an artificial implant, called intraocular lens (IOL).
Treatment of presbyopia in combination with cataract surgery
The choice of the intraocular lens (IOL) is based on preoperative biometric diagnostic tests. An IOL, apart from the ordinary monofocal type, can be multifocal or EDoF to address both presbyopia and cataract.
EDoF: Extended Depth of Focus IOLs
Premium next – generation IOLs that predict distant vision (e.g. driving), intermediate vision (e.g. reading items on a supermarket shelf) and close vision up to a certain point – usually for 40 – 50cm (e.g., sewing) in good lighting conditions.
An EDoF lens creates a single elongated focal point to achieve this wide range of focal distances (no disturbances during night driving, no glare, no halos).
Multifocal IOLs
Premium IOLs that offer the ability to focus at all distances (far, intermediate, near) for facing presbyopia. Their functionality is based on the concept of multifocal contact lenses, which divide their optical section into specific zones, usually concentric. The human brain will adapt and “learn” to select the appropriate focus on the object (distance) the patient desires. Most of the time, there is an adaptation period (learning curve). Postoperatively, the patient normally does not need glasses.
Copyrights by Carl Zeiss Meditec AG