Pathological myopia is a progressive disease with a hereditary element that causes early degeneration of the vitreous humour and the retina. These eyes are prone to early cataracts, retinal detachment, macular holes and other retinal lesions, which cause severe loss of visual acuity. When this occurs, the eye deviates and is unable to hold steady on objects. Periodic check-ups must be performed to detect such disorders before sight suffers irreversible damage. Once eye deviation has appeared, it can be treated with surgery on the extraocular muscles.