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Anterior Segment Intraocular Lens
Yellow Intraocular Lenses – To Block or Not to Block
Elfriede Wenzl,
1
Matthias G Wirtitsch
1,2
and Navid Ardjomand
1
1. Department of Ophthalmology, Medical University Graz; 2. Department of Ophthalmology, Hietzing Hospital, Vienna
Abstract
Yellow filters for the eye have been of interest to ophthalmologists and optometrists for the last 30 years. Certain fish species can change
the colour of the cornea in response to the level of illumination and regulate the amount of short-wavelength light reaching the retina. A
positive influence of yellow eye filters on reduction of chromatic aberration has been found in a fish eye model. Blue-light-filter (yellow)
intraocular lenses (IOLs) were introduced for cataract surgery almost 20 years ago. The main advantage of yellow IOLs is thought to be the
reduction of chromatic aberration under photopic conditions and protection of the retina from phototoxic short-wavelength light, especially
in eyes at risk of age-related macular degeneration (AMD). This article highlights the importance of yellow IOLs for cataract surgery in terms
of quality of vision and AMD protection.
Keywords
Age-related macular degeneration (AMD), chromatic aberration, contrast sensitivity, intraocular lens, blue-light filter, yellow
Disclosure: The authors have no conflicts of interest to declare.
Received: 20 October 2009 Accepted: 18 November 2009
Correspondence: Navid Ardjomand, Department of Ophthalmology, Medical University Graz, Auenbruggerplatz 4, A-8036 Graz, Austria.
E: navid.ardjomand@meduni-graz.at
The fact that short-wavelength blue light has a phototoxic effect on the products and waste products that accumulate in the RPE cells with
retina was discovered in the late 1970s.
1–3
It is known that certain fish ageing and deteriorating cellular function.
8
Lipofuscin contains
species change the colour of their corneas in response to the level of different fluorophores, one of which – A2E – most probably originates
illumination and regulate the amount of short-wavelength light reaching from oxidative damage to the photoreceptor outer segments. These
the retina.
4
It was further proposed that this phenomenon might also A2E-laden RPE cells are likely to mediate the formation of reactive
have a positive influence on visual quality by reducing longitudinal oxygen species, which are speculated to be one of the causes of
chromatic aberration.
4–6
This led to the development of yellow-tinted AMD, particularly in response to short-wavelength light.
9–11
intraocular lenses (IOLs) for cataract surgery in the early 1990s.
7
These
IOLs, first developed and produced by Hoya Healthcare Corporation, Animal experiments have shown the induction of apoptotic cell death
Japan, did not become popular until recent years, when Alcon in the US in photoreceptors and RPE cells after exposure to high-dose white
started a big marketing campaign to relaunch these IOLs worldwide. light.
12
The short-wavelength visible blue light with its high-energy
photons has the power to damage the cellular function of
There is no doubt about the importance of ultraviolet (UV) blockers in photoreceptors and RPE cells. It creates reactive oxygen species that
IOLs, but there is still a lot of discussion about the usefulness of damage the DNA and therefore result in apoptotic cell death. Blue
filtering short-wavelength blue light with IOLs. People advocating light is 50–80 times more harmful than green light. However, red light
these IOLs argue that they might protect the retina from phototoxic is unable to induce retinal damage at a certain intensity.
damage and increase visual quality by reducing chromatic aberration.
Surgeons refusing to use the lens are worried about mesopic and The crystalline lens of the ageing human progressively increases
scotopic contrast and colour sensitivity. This article highlights the pros absorption within the short-wavelength spectrum of visible light.
and cons of blue-light-filter yellow IOLs. During its life the lens becomes increasingly yellowish, acting as a
natural protective filter against blue light. During cataract surgery the
Blue-light-filter Intraocular Lenses and crystalline lens is removed and is replaced by an IOL, dramatically
Age-related Macular Degeneration increasing the transmittance of radiation. This is despite the fact that
Cataracts and age-related macular degeneration (AMD) are the most the removal of the cataractous lens leaves the RPE at an age when its
common causes of visual loss after 60 years of age. AMD has a content of blue-sensitive A2E-laden cells is high and will continue to
complicated pathogenesis involving a variety of hereditary and increase over a lifetime.
13
environmental factors. Lipofuscin in post-mitotic cells, such as the
retinal pigment epithelium (RPE) cells, is considered to be a biomarker In vitro and in vivo studies in animals showed a significantly higher
for cellular ageing. It represents incompletely degraded membrane RPE cell death when irradiating with short-wavelength visible light in
© TOUCH BRIEFINGS 2009 77
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