Spectacles are
needed for fine tuning to normal vision of 6//6N5
Intra Ocular
Lens or Lenses (IOLs) have two main features.
1. The optic portion, the round part of the IOL, which focuses images on the
retina.
2. Two arm-like structures called haptics which are attached to the edge of the
optic. The haptics help maintain the location of the IOL in the capsular bag of
the original human lens.
The
revolutionary ACRYSOF Restor provides vision at all distances without glasses-
in 90% cases. It can be used only in persons with corneal astigmatism less than
0.75 D Cyl.)
The AcrySof
ReSTOR IOLs is a technological breakthrough that combines the strengths of
apodized diffractive and refractive technologies to give patients a full range
of vision - near through distance - and reduces dependency on reading glasses
or bifocals following cataract surgery. (Apodization is used in telescopes and
microscopes to improve the image quality, but apodization on IOLs is for the
first time!).
Diffraction is the spreading of light when the light passes through
discontinuities (i.e. step heights or edges). Apodization is the gradual
reduction or blending of the step heights to create a smooth transition of
light between the distance, intermediate and near focal points. The AcrySof
ReSTOR IOLs consists of an apodized diffractive optic, at the centre of the
lens. This area consists of 12
concentric rings of gradually decreasing step heights that allocate energy
based on activity and lighting conditions, creating full range of vision from
near to far and everything in between. The step heights range from 1.3 microns
to 0.2 microns. (To appreciate the finesse of this technology: one strand of
human hair is 60 microns thick; an RBC is 7 microns). The step heights are
blended to allow only one wave length of light (i.e. 550mm) to pass through thereby
minimizing scattering of light and hence glare and halos. The outer refractive area of the optic
focuses for distance vision. This means
that the series of tiny steps in that centre area work together to focus light
for near (objects within 16 inches) through distance vision (objects within 7
feet). Refraction is the redirection of light rays as they pass through the
lens. The refractive region of the AcrySof ReSTOR IOL bends light as it passes
through the lens to a focal point on the retina. This outer ring of the AcrySof
ReSTOR IOL surrounds the apodized diffractive region and is dedicated to
focusing light for distance vision.
The newly
designed Alcon ACRYSOF ReSTOR IOL has the same basic shape and identical
material as the Alcon ACRYSOF Single-Piece monofocal IOL. The IOL allows for
near (reading) and intermediate (computer work) vision and distance vision
without glasses in 90% of the cases. You may therefore be more independent of
glasses for daily tasks. The choice of the IOLs depends largely on the needs of
individual patients. If the patient is looking for complete riddance from
glasses, ACRYSOF ReSTOR IOL should be preferred.
90% of the
ReSTOR surgeries done at Roshan
Eye Care
Hospital “NEVER” required
glasses for day to day activities! Glare and halos is minimal compared to other
IOLs. Roshan Eye Care Hospital found that this tiresome
complaint can be minimized, if the Acrysof ReSTOR IOL is perfectly centred in
the bag, in the visual axis.