Microphthalmia is an eye abnormality that arises before birth. In this condition, one or both eyeballs are abnormally small. In some affected individuals, the eyeball may appear to be completely missing; however, even in these cases some remaining eye tissue is generally present. Such severe microphthalmia should be distinguished from another condition called anophthalmia, in which no eyeball forms at all. However, the terms anophthalmia and severe microphthalmia are often used interchangeably. Microphthalmia may or may not result in significant vision loss.\n\nPeople with microphthalmia may also have a condition called coloboma. Colobomas are missing pieces of tissue in structures that form the eye. They may appear as notches or gaps in the colored part of the eye called the iris; the retina, which is the specialized light-sensitive tissue that lines the back of the eye; the blood vessel layer under the retina called the choroid; or in the optic nerves, which carry information from the eyes to the brain. Colobomas may be present in one or both eyes and, depending on their size and location, can affect a person's vision.\n\nPeople with microphthalmia may also have other eye abnormalities, including clouding of the lens of the eye (cataract) and a narrowed opening of the eye (narrowed palpebral fissure). Additionally, affected individuals may have an abnormality called microcornea, in which the clear front covering of the eye (cornea) is small and abnormally curved.\n\nBetween one-third and one-half of affected individuals have microphthalmia as part of a syndrome that affects other organs and tissues in the body. These forms of the condition are described as syndromic. When microphthalmia occurs by itself, it is described as nonsyndromic or isolated.

Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.

Primary or spontaneous detachment of the retina occurs due to underlying ocular disease and often involves the vitreous as well as the retina. The precipitating event is formation of a retinal tear or hole, which permits fluid to accumulate under the sensory layers of the retina and creates an intraretinal cleavage that destroys the neurosensory process of visual reception. Vitreoretinal degeneration and tear formation are painless phenomena, and in most cases, significant vitreoretinal pathology is found only after detachment of the retina starts to cause loss of vision or visual field. Without surgical intervention, retinal detachment will almost inevitably lead to total blindness (summary by McNiel and McPherson, 1971).

In wound repair, neovascularization (NV) involves the sprouting of new vessels from pre-existent vessels to repair or replace damaged vessels. In the retina, NV is a response to ischemia. The NV adheres to the inner surface of the retina and outer surface of the vitreous. NV are deficient in tight junctions and hence leak plasma into surrounding tissue including the vitreous. Plasma causes the vitreous gel to degenerate, contract, and eventually collapse which pulls on the retina. Since retinal NV is adherent to both retina and vitreous, as the vitreous contracts the NV may be sheared resulting in vitreous hemorrhage or the NV may remain intact and pull the retina with the vitreous resulting in retinal elevation referred to as traction retinal detachment.

A wrinkle of retinal tissue projecting outward from the surface of the retina and visible as a line on fundoscopy.

Diminished clarity of vision.

A severe form of myopia with greater than -6.00 diopters.

An area of the retina that is buckled so that a sector-shaped sheet of retina lies in front of the normal retina. This feature is of congenital onset.

An eye that is more deeply recessed into the plane of the face than is typical.

Reduced depth of the anterior chamber, i.e., the anteroposterior distance between the cornea and the iris is decreased.

A type of retinal exudate located in the subretinal space between the sensory retina and the retinal pigment epithelium.

The presence of an increased number of twists and turns of the retinal blood vessels.

Retinal exudate within the retinal tissue itself.

A small break in the retina.