Instrument that measures the distance between the top of the cornea lepithelium and the bottom of the cornea l endothelium used as diagnostic testing device measuring for cornea l thickness.
Exam for measuring cornea l thickness.
Non-inflammatory swelling/elevation of the optic nerve often due to increased intracranial pressure or space-occupying tumor.
Used on prescriptions to indicate the distance between the pupils of both eyes.
Pellucid marginal degeneration:
A bilateral, noninflammatory, peripheral corneal thinning disorder, which is characterized by a peripheral band of thinning of the inferior cornea.
Ability to perceive the presence, motion, or color of objects outside the direct line of vision.
Personal Best Vision:
Best possible vision for each individual as corrected.
Phacoemulsification cataract surgery:
removal procedure which involves making a tiny incision, about 1/8″ long. A pen-like instrument, inserted through the opening, is used to emulsify and aspirate the clouded lens material, using gentle sound waves. Then an intraocular lens is inserted into place.
Phacofracture cataract surgery:
Cataract surgery in which the lens is removed through a small incision by “fracturing” it into several small segments, rarely used today.
Phakic Intraocular Lenses (IOLs):
Placed inside the eye without removing the natural lens, and performs much like an internal contact lens.
A common device found in most eye doctor’s offices, with mulitple lenses, used to measure refractive errors. A phoropter calculates the prescription required for corrective lenses.
Focusing of powerful light rays onto tiny spots on the back of the eye, producing heat, which seals retina l tears and cauterizes small blood vessels.
Sensitivity to light.
Microscopic light-sensitive cells that are located in the retina calledrods and cones . There are approximately 7 million cones and 125 million rods
Photo Refractive Keratectomy (PRK):
Surgery in which a small area on the cornea lepithelium (surface cells) is gently polished away. The laser then reshapes the cornea l surface in exactly the same way as for LASIK surgery.
Irritation caused degeneration of the conjunctiva resulting in a thickening and yellowing of the normally thin transparent tissue.
Type of conjunctivitis, commonly seen in children.
The thin membrane in the eye that holds the crystalline lens in place.
The back section of the eye’s interior.
Posterior optical segment:
Part of the eye posterior (behind) to the crystalline lens , including the vitreous, choroid retina and optic nerve.
Posterior Vitreous Detachment (PVD):
Separation of the vitreous body from its attachment from the retina l surface due to shrinkage from degenerative or inflammatory conditions or trauma. An age-related condition.
Surgical procedure that attempts to correct presbyopia.
Inability to maintain a clear image (focus) as objects are moved closer. Presbyopia is due to reduced elasticity of the lens with increasing age.
Amount of vision correction necessary, written in a form that can be utilized during the manufacture of corrective lenses or to configure a laser machine.
Acronym for Photo-Refractive Keratectomy, which is a procedure involving the removal of the surface layer of the cornea ( epithelium ) by gentle scraping and use of a computer-controlled excimer laser to reshape the stroma .
Bifocal or trifocal lenses which appear to be single vision with no distinct lines between the various focal lengths.
Treatment for dry eye in which plugs are inserted into the punctum in order to retain lubricating tears naturally produced by the eye.
The hole in the upper and lower eyelids through which tears exit the eye. In patients with dry eyes, temporary or permanent plugs may be inserted to help keep tears in the eye. Tears flow through the punctum to the nose, which is why people often experience a runny nose when crying.
Black circular opening in the center of iris through which light passes into thecrystalline lens . It changes size in response to how much light is being received by the eye, larger in dim lighting conditions and smaller in brighter lighting conditions.
Constriction and dilation of the pupil due to stimulation by light or accommodation.