Pathology

Cornea:

The most common corneal disorders are the following:

  • Bullous Keratopathy - blisters on the front of the cornea (epithilial bullae).

  • Corneal abrasion - a medical condition involving the loss of the surface epithelial layer of the eye's cornea as a result of trauma to the surface of the eye.

  • Corneal dystrophy - a condition in which one or more parts of the cornea lose their normal clarity due to a buildup of cloudy material.

  • Corneal ulcer - an inflammatory or infective condition of the cornea involving disruption of its epithelial layer with involvement of the corneal stroma.

  • Corneal neovascularization - excessive growth of blood vessels from the limbal vascular plexus into the cornea, caused by deprivation of oxygen from the air. (neo=new).

  • Fuchs' dystrophy - Can cause cloudy morning vision that improves as the day goes on. Endothelium layer (responsible for maintaining the amount of fluid in the eye) of the cornea begins to degenerates. Vision declines because of corneal edema and can cause bullous keratopathy.

  • Keratitis - inflammation of the cornea.

  • Keratoconus - a degenerative disease, the cornea thins and changes shape to be more like a cone.

  • Pachymetry - Measures corneal thickness

  • EZ Method - Measures depth of the Anterior Chamber

Pupil/IRIS

A condition called bene dilitatism occurs when the optic nerves are partially damaged. This condition is typified by chronically widened pupils due to the decreased ability of the optic nerves to respond to light. In normal lighting, people afflicted with this condition normally have dilated pupils, and bright lighting can cause pain. At the other end of the spectrum, people with this condition have trouble seeing in darkness. It is necessary for these people to be especially careful when driving at night due to their inability to see objects in their full perspective. This condition is not otherwise dangerous.

Aniridia - Absence of the Iris, usually congenital or from injury.

Iris Hypoplasia - Irregular or under development of the Iris

Persistent Pupillary Membrane - (PPM) Strands of membranes across the pupil.

UVEA

Uveitis is the inflammation of the UVEA

Anterior Chamber

Hyphema, anterior uveitis and glaucoma are three main pathologies in this area

Hyphema: Blood in the anterior chamber that may clear up on it’s own however complications may occur such as Introcular pressure, atrophy of the optic nerve, staining, and loss in accommodation.

Anterior Uveitis: (see Uveitis above)

Glaucoma: Increased pressure (introcular pressure) in the eyes causing damage to the optic nerve, and can lead to blindness. Not associated with symptoms or pain. Exact causes are being researched. Open Angle Glaucoma is the most common (about 90%) in patients.

Eyelids

Pstosis, a weak a droopy eyelid. Generally associated with redness, burning, blurred vision, irregular pupil, photophobia, headaches. Requires urgent treatment.

Keratoconjunctivitis sicca (KCS) or Dry Eyes can be a result of dysfunctional meibomian glands as a result of tears being evaporated or low production of tears. Causes can be linked to CVS (computer vision syndrome, pregnancy, contact lens use, meibomian gland dysfunction, vitamin A deficiency, LASIK, Aging, blood pressure medication, & smoking.

Lens

Cataracts: Opacities that block light and impair vision. Can be caused by age or damage to the lens causing it to become more opaque. Diabetes increases the risk factor for cataracts.

Presbyopia: Age related (usually around age 40). The lens hardens and loses it’s ability to change shape and accommodate on near objects.

Aphakia: Removal of crystalline lens

Ectopia Lentis: Displacement of lens from its normal position.

Choroid

Drusen: Associated with aging, whitish/yellowish buildup between Bruch’s membrane and Retina. Large build up can be a sign of AMD (aged related macular degeneration).

Glaucoma

Two forms - Closed Angle (blockage occurs at the entrance), & Open Angle (blockage occurs on the inside). Blockage of fluid from draining from the eye increases pressure in the eye. The increased pressure of the eye causes damage to the optic nerve. The optic nerve cannot properly function and vision is affected, there are generally no symptoms or pain.

The Narrow Angle is located between the iris and the cornea.

Open Angle Glaucoma is more common, in about 90% of cases. This is when the there is no blockage in the angle, but the eye’s drainage canals become clogged over time. The clogging causes increased build up of fluid and pressure in the eye.

Closed Angle Glaucoma is a medical emergency because vision can be lost within a day. Laser Iridotomy is a surgical procedure that creates a small hole in the iris to release fluid in the eye. The surgery is often recommended by ophthalmologists before closed angle glaucoma is detected as a preventative measure.