Acute nearsightedness develops in individuals whose ocular axial length is extremely long in relation to the refractive powers of the cornea and the ocular lens. A nearsighted person who requires correction of -6.5D or beyond is generally considered to have acute or high myopia. This type of visual dysfunction requires special spectacles and contact lenses that are powerful refractors of light yet cause a minimal amount of optical disturbance. Contact lenses with at least one aspheric surface, however, tend to provide the best visual clarity for high myopes.
Certain anti-epilectic medications can produce a temporary state of high myopia known as acute transient myopia. Common symptoms of the onset of this type of nearsightedness are blurred vision and pain in or just behind the eyes. An eye specialist might recommend discontinuation of the medication to acute myopes at risk for angle-closure glaucoma.
The shape and consistency of the acute myopic retina is often different from the retina of a person with little or no visual dysfunction. For this reason, retinal ruptures as well as detachment of the retina are more likely to occur in a highly myopic person. Deformation of the retinal macula which surrounds the area of sharpest vision, the fovea, is sometimes seen in an acute myope, resulting in slight distortions in vision.
While hemorrhages of the retina are fairly simply treated with laser procedures, retinal detachment is an acute, vision-threatening condition that must be treated with more sophisticated forms of surgery. The characteristic symptoms of imminent retinal detachment are bright flashes of light followed by darkness that unfurls like a curtain. If these symptoms are experienced, an intensive care eye unit should be visited immediately.