Description:
This is a surgical treatment for age-related macular degeneration.
Age-related macular degeneration is the commonest cause of irreversible blindness in developed countries.
The macula is the part of the retina that provides central vision. Ninety per cent of people with age related macular degeneration have atrophic, or 'dry', macular degeneration, characterised by thinning of the macular retina. The other 10% have neovascular macular degeneration (also known as 'wet' or exudative macular degeneration). This type is characterised by the growth of new vessels in the choroid layer underneath the retina, which can threaten vision if they leak and cause scarring.
The new vessels are described according to whether they can be seen clearly ('classic') or poorly ('occult') on a test called fluoroscein angiography. Occult new vessels probably lie more deeply in the choroid than classic new vessels. New vessels in the foveal part of the choroid (subfoveal vessels) are potentially the most disabling, because the fovea is the central part of the macula, which is responsible for the sharpest vision.
The visual prognosis of wet macular degeneration is poor. Without treatment, 40% of people with occult neovascularisation develop severe visual loss within 2 years. People with neovascularisation in one eye have about a 50% chance of developing a similar lesion in the fellow eye within 5 years.
Macular translocation involves moving the macula so that the fovea lies over a healthier part of the choroid layer beneath it. This may involve making a cut around the whole periphery of the retina and rotating the retina (macular translocation with 360° retinotomy). Another approach is to make a shorter cut in the retina and fold the outer layers of the eye (scleral imbrication) so that the underlying choroid is moved slightly relative to the macula (limited macular translocation).
Alternative treatments include photodynamic therapy.
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