My friend and colleague was quoted in this news story in the Times Colonist about the link between vision problems and attentional anomalies. If you or your child has suspecyed ADHD, a comprehensive, vision examination that includes the determination of oculomotor, accommodative and vergence abilities (and more!) is essential. You should also ask your eye doctor if they have the assessment tools available (like the TOVA [Test of Variables Attention] to help determine if ADHD or other problems with attention are present.
".....Dr. Patrick Quaid, an expert in double vision, is head of the Guelph Vision Therapy Centre. He says that double vision must be taken seriously because its causes can range from brain tumour, concussion or inflammation of an artery to simple dysfunction of ocular muscles. Fortunately, when adults notice DV, they know something is wrong and demand quick attention.
But Quaid says children with ADHD often get either a delayed diagnosis or no diagnosis of ocular disorder. Doctors treating a child with ADHD rarely consider arranging for an eye examination to detect ocular malfunction.
The most commonly encountered abnormality is “convergence insufficiency,” or difficulty keeping the eyes tuned when reading. These kids’ eyes do not work in unison due to an imbalance of muscle control. Consequently, they see double when reading, frequently lose their place, find reading frustrating and shy away from it, which affects their learning......"- See more at: http://www.timescolonist.com/life/the-doctor-game-children-s-vision-problems-mimic-adhd-1.1305479#sthash.WAEsvPGZ.dpuf