Types Of Cataracts
While most types of cataracts develop as a result of age, there are a variety of other types that can develop, as young as infancy.
Of the age-related types of cataracts, there are three popular types; all of the varieties share the similar symptom of a cloudy, opaque gathering in the lens of the eye that restricts or obscures the range and clarity of vision.
Nuclear Sclerotic Cataracts
Nuclear sclerotic cataracts are by far the most common type of cataract, and almost exclusively develop as a result of aging. In this variety of cataract, there is a slowly increasing buildup of yellow cloudiness around the ‘nucleus,’ or center of the lens.
This cloudiness eventually begins to harden, and the obscuring of vision is so gradual that patients may not even notice the changes. In some cases, patients can notice a slight and temporary improvement in near vision, before all vision drops off significantly.
Cortical cataracts are also age-related, though they are not as common as the nuclear sclerotic varieties. Cortical cataracts begin with the appearance of an opaque white cloudiness in the outer part of the lens. This outmost portion of the lens is referred to as the peripheral section, or the cortex.
This type of cataract spreads, and often looks like the spokes of a wheel that point inward to the center of the lens. These cloudy spokes tend to cause light to scatter.
Posterior Subcapsular Cataracts
Posterior Subcapsular Cataracts (PSCs) are characterized by an opaque cloudiness that develops on the back of the lens, immediately underneath the lens’ outermost layer. This is the third and final type of age-related cataracts.
This generally causes sensitivity to light, obscured near vision and a ‘halo effect’ around bright lights. These cataracts are more common among steroid users and patients with diabetes.
The first kind of non-age related cataract, traumatic cataracts can develop from direct trauma or injury to the lens of the eye. This can stem either from a blunt impact or some kind of piercing, and may not develop immediately.
These cataracts may manifest years after the original traumatic event that caused them, clouding the lens and obscuring vision like other kinds of cataracts. Exposure to certain kinds of chemicals may also influence the development of traumatic cataracts.
Inherited cataracts, also known as congenital cataracts, affect infants when they are born, but may not be significant enough to cause vision loss. Sometimes, abnormal lens development during pregnancy may result in these cataracts. Because these cataracts are often off-center in the lens or are small enough to avoid impairing vision, congenital cataracts sometimes do not need to be removed. Congenital cataracts, even if not removed right away, should be closely monitored so that they do not eventually threaten vision development.
Other than cataracts that form as a result of a traumatic event or those that are genetically inherited, most varieties of cataracts only manifest as a result of aging. While each formative condition is unique, each one results in obscured vision.