see "Coat’s Disease"

Coat’s Disease is also called congenital telangiectasia. It is related to type 1 macular telangiectasia, since it involves localized dilations, or aneurysms, of blood vessels throughout the retina. Leber’s Miliary Aneurysm is an interchangeable term for the mildest form of Coat’s Disease; the mild form often involves no vision loss and no exudates. In more severe forms, the aneurysms bleed into the back of the eye, and cholesterol from the leaking blood is left behind on the retinal cells.
Coat’s Disease is similar to type 1 macular telangiectasia because it usually affects only one eye and usually occurs in males. The difference is that Coat’s Disease is present at birth and is very often diagnosed in early childhood. Some researchers have suggested that Coat’s Disease may be caused by a genetic mutation, but this is not known for certain.
Coat’s Disease, in its more severe form, causes a gradual deterioration of vision and often results in retinal detachment. The progression of Coat’s Disease can sometimes be stopped by laser surgery or cryotherapy. These treatments can not be used if the capillaries affected are near the optic nerve, or it Coat’s Disease has progressed too far. Few children with Coat’s Disease are diagnosed at a stage at which surgery or cryotherapy can stop the progression of the disease because they are often too young to explain the symptoms of the disease or describe their vision loss. In addition to retinal detachment, glaucoma, atrophy, or cataracts may occur as Coat’s Disease progresses. Unfortunately, removal of the affected eye may be an eventual outcome.
A diagnosis of Coat’s Disease can be frightening and devastating—for both the child who has received the diagnosis and his parent. It is important for a parent to try to maintain an optimistic attitude and encourage his or her child to adapt to vision loss by relying on— and protecting—the non-Coat’s eye.

Central serous chorioretinopathy (CSC) occurs when fluid collects between the photoreceptor layer and the pigment epithelial layer of the retina. The exact reason for the collection of fluid in the subretinal space is not well understood. It is known that most individuals who develop CSC are young adult males, and many live a high-stress lifestyle. This has lead researchers to believe that there may be a link between CSC and the stress hormones epinephrine and cortisol.
The accumulation of fluid under the retina causes blurriness and distortion in the center of vision. Often, the accumulation of fluid will cause a serous pigment epithelial detachment, causing even more fluid to leak into the subretinal space. Laser photocoagulation is sometimes used if there are areas that are allowing fluid to leak into the space, but it is a controversial treatment. Left untreated, CSC will often resolve itself, and most vision will be restored within six months. Central vision may remain slightly distorted, and night vision may be reduced. People who have experienced CSC should be aware that recurrences sometimes occur.

see "Macular Fibrosis"

The choroid is the nourishing layer of the eye located between the retina and the sclera, and is filled with tiny blood vessels. The choroid supplies the outer layer of the retina with blood. In the womb, the choroid gives rise to all other structures of the eye.  

Cataracts are the opaque, or milky, areas that can form in part or all of the crystaline lens of the eye. They often start with only a slight disturbance of normal vision, often going unnoticed for years, and can slowly increase in opacity until they completely interfere with vision. Some of the early effects of a cataract are a decrease in contrast sensitivity and color intensity, but eventually they also decrease visual acuity.
There are many possible reasons for developing a catartact, including age, excess exposure to ultraviolet light and radiation, physical trauma to the eye, secondary effects of diseases such as diabetes or hypertension, and the side effects of certain drugs such as corticosteroids. There may also be a genetic component to certain forms of cataracts. Cataracts are classified by a number of terms that include: partial, complete, hard, soft, stationary or progressive, nuclear, cortical, mature, and hypermature. They may also be classified as being posterior or anterior, referring to thier location.
Surgery ro remove "mature" cataracts is common and is often performed with only a local anaesthetic on an outpatient basis, allowing the patient to go home the same day. The surgery removes the old lens and replaces it with a plastic one, referred to as an intraocular lens, or IOL. Endophthalmitis and retinal detachment are some of the possible complications of cataract surgery.