Myopia may be genetic

According to a study carried out in 2004 by the John Hopkins University School of Medicine, Baltimore (USA), 90 out of 100 children in China are myopic. In Canada, myopia afflicts 6% of 6-year-old children and 20% of twelve-year-olds. In Italy, 12 million people are nearsighted.

Mario Stirpe, chairman of the Bietti Foundation, said that 'genetic factors are almost certainly' at the basis of the disorder. As he explained to Repubblica Salute, 'the disorder continues to increase also in Italy, it is very worrying and unexplainable, but we think it may be genetic in origin. But the myopia gene has not yet been isolated so we cannot be certain about this'.

The first signs of myopia appear between the age of 7 and 12 and it continues to worsen until 20 years of age in women and around 22 in men; it then stabilizes or becomes 'pathologic'. The eye lengthens in the most sensitive area of the retina that provides image details and 'causes tissue rarefaction, like a stocking that rips when it is pulled, and this could lead to other pathologies. In a normal eye, for example, senile macular degeneration might develop after the age of 55, with severe myopia it occurs even in the very young'.

According to professor Stirpe, in cases of conjunctivitis or allergy people who are nearsighted should continue to wear glasses even if they use contact lenses; moreover, those who consider laser surgery to treat myopia must be told about the possible disturbances afterwards, like nocturnal flashes and dryness. Stirpe also believes it is inadvisable to correct severe myopia because of the risk of retinal complications.

Stirpe also dismisses old notions such as the belief that myopic women, and highly myopic women in particular, can't breastfeed. 'It isn't true', he said, 'sight doesn't worsen. If it looks as though the birth is going to be difficult and lengthy, a Cesarean section is advisable so as not to run the risk of retinal detachment, the tendency with myopia'.

Lastly, Stirpe said that sight should not be tested shortly after removing contact lenses: the lens modifies the curve of the cornea and this gives false results. It is better to wait at least one day and three days would be even better.

(Source: Repubblica Salute)