Classification Cross-sectional view, showing the position of the human lens Ultrasound scan of a unilateral<unk>  seen in a fetus at twenty weeks of pregnancy<unk> s may be partial or complete, stationary or progressive, hard or soft. The main types of age-related<unk> s are nuclear sclerosis, cortical, and posterior subcapsular. Nuclear sclerosis is the most common type of<unk> , and involves the central or 'nuclear' part of the lens. This eventually becomes hard, or 'sclerotic', due to condensation on the lens nucleus and the deposition of brown pigment within the lens. In its advanced stages, it is called a brunescent<unk> . In early stages, an increase in sclerosis may cause an increase in refractive index of the lens. This causes a myopic shift (lenticular shift) that decreases hyperopia and enables presbyopic patients to see at near without reading glasses. This is only temporary and is called second sight. Cortical<unk> s are due to the lens cortex (outer layer) becoming opaque. They occur when changes in the fluid contained in the periphery of the lens causes fissuring. When these<unk> s are viewed through an ophthalmoscope, or other magnification system, the appearance is similar to white spokes of a wheel. Symptoms often include problems with glare and light scatter at night. Posterior subcapsular<unk> s are cloudy at the back of the lens adjacent to the capsule (or bag) in which the lens sits. Because light becomes more focused toward the back of the lens, they can cause disproportionate symptoms for their size. An immature<unk>  has some transparent protein, but with a mature<unk> , all the lens protein is opaque. In a hypermature or Morgagnian<unk> , the lens proteins have become liquid. Congenital<unk> , which may be detected in adulthood, has a different classification and includes lamellar, polar, and sutural<unk> s.<unk> s can be classified by using the lens opacities classification system LOCS III. In this system,<unk> s are classified based on type as nuclear, cortical, or posterior. The<unk> s are further classified based on severity on a scale from 1 to 5. The LOCS III system is highly reproducible.
Cataract
Ocular hypertension
Glaucoma
Refractive error
Vitreoretinopathy
Oculomotor nerve palsy
Auditory neuropathy
Aberrations of the eye