For cataract treatment, bet on PREMIUM lenses – get rid of distance glasses as reading glasses

Patients often wonder whether to choose cataract surgery under the National Health Service and accept the standard monofocal lens offered therein, or to seek an alternative procedure in a private facility, and thus the possibility of a maximally individualized selection of implantable lenses.

Until recently, the decision was determined by the waiting time for the procedure. Today, however, one does not have to wait long for cataract surgery in a state facility. However, the fundamental limitation remains the lack of the possibility of individual lens selection.

A reimbursed monofocal lens means for the patient that he will be able to see clearly either up close or far away – for example, he will be able to drive a car without glasses, but will already need them for reading.

In a private clinic, in addition to the absolute medical indications, the individual needs of the patient are always taken into account in the calculation of the implantable lens when planning cataract surgery.

During cataract surgery not only short- or farsightedness, but also astigmatism and presbyopia can be corrected. Thus, when choosing PREMIUM lenses, in addition to cataract removal, the patient can count on very good visual acuity for distance, nearsightedness (35-40 cm) and intermediate distance (60-90 cm).

We divide premium lenses into two main groups:

• Toric lenses

Toric monofocal lenses – in addition to removing cataracts, they allow to eliminate astigmatism, provide sharp vision for either distance or near. Toric monofocal lenses will make reading glasses indispensable to the patient.

Toric multifocal lenses – in addition to the removal of cataracts allow to eliminate astigmatism, provide sharp vision for distance, near and intermediate distances. Multifocal toric lenses allow to eliminate corneal astigmatism, resulting in the fact that the correction of vision defects with glasses will no longer be necessary after surgery.

• Multifocal lenses

In addition to removing cataracts, multifocal (trifocal/multifocal) lenses guarantee the elimination of presbyopia and very good visual acuity for distance, near (35-40 cm) and intermediate distance (60-90 cm).

Among multifocal lenses, we distinguish lenses:

• refractive
• diffraction
• refractive-diffraction

In refractive lenses, the refraction and reflection of light at the border of optical zones causes an increase in higher-order aberrations and undesirable photo-optical phenomena of the glare and halo type, especially intensifying in extremely unfavorable conditions, i.e. with a negligible amount of light, such as when driving at night.

In diffraction lenses, light rays, after passing through a diffraction grating, are deflected and then interfered with, creating an additional wavefront and thus a new image.

Thus, if we have bifocal lenses, two images (far and near) are formed on the retina at the same time, or even three – if we have trifocal lenses (far, near, intermediate distance). The visual system, together with the central nervous system, makes a selection selecting one sharp image and suppressing the other waves – a phenomenon of neuroadaptation occurs, which lasts on average from one to three months, and even longer in some patients.

In refractive-diffractive lenses (also known as pseudo-accommodative lenses), a central diffractive zone allows for near and far vision, while a peripheral refractive zone with breaking power allows for far vision.

• EDOF (extended depth of focus) lenses

EDOF are intraocular lenses with extended depth of field (extended focal length), combining the advantages of monofocal and multifocal lenses. This means that they provide sharp vision over a wide range of distances – from far to intermediate.

EDOF lenses are an excellent choice for people who, due to their active lifestyles, value complete or almost complete freedom from glasses. They enable clear vision of objects at various distances: from far to medium distance (more or less at arm’s length). Importantly, extended depth-of-field lenses reduce the visual side effects usually associated with multifocal lenses, such as the halo effect, and significantly increase the comfort of vision after sunset (less photo-optical interference is experienced) – you can then, for example, drive without problems.

Extended focal length lenses provide a high level of independence from glasses, but the resulting quality of vision is an individual matter and can vary from patient to patient.

All types of PREMIUM lenses can be equipped with UV filters and/or a blue light filter (blue light filter) – then they eliminate the harmful part of the light beam, protect on the retinal pigment epithelium and reduce the risk of developing macular degeneration (AMD), the most common cause of irreversible blindness in patients over 60. year of age.

Both PREMIUM and standard monofocal lenses can have an aspherical design to reduce spherical aberrations. The phenomenon of spherical aberrations is experienced by the patient as a halo effect around light sources or blurring of the image resulting from greater refraction of light waves in the peripheral part of the cornea compared to the central part. Aspheric lenses have a modified optical part so that light rays passing through the peripheral optical part focus in the same place as those passing through the central part.

Such lenses are implanted in people who often drive at night or work in poor lighting conditions.

Modern ophthalmology has high hopes for accommodative lenses. It is an ultra-modern product of advanced biomedical engineering that allows to reproduce the natural mechanisms of eye accommodation in a close-to-natural way. This means acute near vision (reading), intermediate vision (computer work, socializing, glancing at the dashboard of a car), and distance vision (driving, observing distant landscapes).

It is a lens that combines excellent visual acuity with the best possible contrast and realistic color perception. By correcting imaging errors that can be caused by artificial lenses (aberrations), it improves visual perception, especially at dusk or in difficult weather conditions.