Orthoptics is a profession allied to medicine whose primary remit is the diagnosis and non-medical management of strabismus (squint), amblyopia (lazy eye) and eye movement disorders. The word orthoptics comes from the Greek words ὀρθός orthos, "straight" and ὀπτικός optikοs, "relating to sight" and much of the practice of orthoptists concerns refraction and muscular eye control. Orthoptists are trained professionals who specialize in orthoptic treatment, but generally without any medical qualifications. With specific training, in some countries orthoptists may be involved in monitoring of some forms of eye disease, such as glaucoma, cataract screening and diabetic retinopathy