Some children say that they have difficulties seeing the classroom board. Does that mean that they have myopia (shortsightedness)?
Not necessarily. Difficulties seeing in the distance may be caused by a lesser known condition referred to as pseudo myopia. Pseudo myopia causes difficulties seeing things clearly in the distance as does myopia. However, unlike myopia, where the distance vision is always blurry, pseudo myopia causes the distance vision to become blurry on occasion (intermittently). A child experiencing symptoms of pseudo myopia may report that the classroom board is easy to see earlier in the school day and less so in the afternoon. Alternatively, they may report that the board is blurry after they have done a bit of reading and it takes a while to become clear.
The presence of pseudo myopia suggests that something is not right with the visual system. Frequently pseudo myopia occurs when the binocular vision system is not functioning optimally. A well-adjusted binocular vision system should focus accurately and efficiently when reading. The eyes should also converge (point in) to look at the text on the page when reading. If the accommodation or convergence is not working as it should binocular vision issues arise. One way the eyes can deal with this binocular vision problem is to create pseudo myopia. The creation of pseudo myopia can reduce the stress on the visual system while the child reads but it creates a new problem; inability to see the board clearly.
Behavioural Optometrists recommend correcting the underlying binocular vision issue in order to eliminate the symptoms caused by pseudo myopia. Treatment usually involves wearing glasses for reading and other near tasks. Taking regular breaks from near tasks and holding reading material at the correct working distance are also important. Vision therapy may also support the binocular vision system by developing accommodation and convergence skills.
Left untreated, pseudo myopia may continue to create challenges seeing things clearly on the classroom board. The child may also experience headaches, near blur or eye strain when performing near tasks for extended periods. Pseudo myopia may also have an adverse effect on concentration, comprehension and fluency when reading. In some instances, a child with pseudo myopia may in time develop myopia (Shortsightedness). This would result in the classroom board appearing blurry all the time.
If you suspect your child may be experiencing symptoms of pseudo myopia the best course of action is to have a comprehensive eye examination including a full binocular vision assessment. Eye examinations should be performed every two to three years while a child is studying, more frequently if symptoms are present.