Optic nerve and open angle glaucoma

Halos around lights Eye redness If left untreated, glaucoma will eventually cause blindness. Even with treatment, about 15 percent of people with glaucoma become blind in at least one eye within 20 years.

Migraine headaches which may be associated with low tension glaucoma Smoking history: Smoking generally exacerbates optic nerve damage in most forms of glaucoma. After obtaining the history, the eye doctor optometrist or ophthalmologist examines the following: Visual acuity, determined by having you read letters on an eye chart Eye pressure: Tonometry is the measurement of intraocular pressure IOP.

Some instruments test pressure using a puff of air. Other instruments such as contact tonometers are typically used after instilling a numbing drop on the eye. Examination of the front part of the eye: A slit lamp is an upright microscope used by eye doctors to examine the parts of the eye that can be affected by glaucoma, including the cornea, anterior chamber, iris, and lens.

Examination of the optic nerve fundoscopy: Using either an ophthalmoscope or the slit lamp microscope and a lens, the examiner can look through the pupil and see the portion of the optic nerve that is inside the eye and the layers of nerve fibers as they spread out over the retina in the eye the nerve fiber layer.

The examiner is looking for signs of optic neuropathyor thinning atrophy of the nerve tissue. Often the pupils need to be dilated for an adequate view. The optic nerve head is referred to as the disc; within the disc, there is a concave area, which is referred to as the "cup.

The nerve can be viewed using a direct ophthalmoscope, although the 3-D view at the slit lamp or the indirect ophthalmoscope gives a better assessment of the cupping.

A baseline photograph of the optic disc fundus photography may be taken for future reference. Pachymetry or corneal thickness is measured with ultrasound. A thinner cornea is associated with higher risk of glaucoma. Gonioscopy allows the examiner to view the angle of your eye.

This is the area between the peripheral iris and cornea where circulating fluid within the eye aqueous drains back into the bloodstream through a sieve-like structure called the trabecular meshwork.

A gonioscopic lens is a special contact lens with mirrors that permits the examiner to determine if the angles are open as is the case in primary open-angle glaucoma or narrowed, closed, scarred, or damaged as seen in other forms of glaucoma.

The anatomy of the angle can also be visualized using ultrasound or OCT optical coherence tomography. If the eye doctor is concerned that the appearance of the optic nerve suggests possible glaucoma, a nerve fiber analysis NFA can be done with OCT optical coherence tomography.

This measures the topography and thickness of the nerve tissue and is especially useful in determining which regions of the nerve appear most thinned.

Thinning of the nerve tissue is one of the earliest signs of glaucoma. Sequential exams can be compared so any progressive thinning over time can be detected.Mar 12,  · The main clinical features of primary open-angle glaucoma are an open iridocorneal angle and cupping of the optic-nerve head (or optic disk), with corresponding loss of visual field.

Elevated intraocular pressure is not part of the clinical definition because primary open-angle glaucoma can occur when intraocular pressure is normal (typically. Glaucoma is a group of diseases that can damage the eye’s optic nerve and result in vision loss and blindness.

Glaucoma - Wikipedia

Open-angle glaucoma, is the most common form of the disease. Facts About Glaucoma. In open-angle glaucoma, the angle in your eye where the iris meets the cornea is as wide and open as it should be, but the eye’s drainage canals become clogged over time, causing an increase in internal eye pressure and subsequent damage to the optic nerve.

Mar 12,  · Glaucoma is a chronic, degenerative optic neuropathy that can be distinguished from most other forms of acquired optic neuropathy by the characteristic appearance of the optic nerve.

In glaucoma, the neuroretinal rim of the optic nerve becomes . In open-angle glaucoma, the angle in your eye where the iris meets the cornea is as wide and open as it should be, but the eye’s drainage canals become clogged over time, causing an increase in internal eye pressure and subsequent damage to the optic nerve.

Open-angle glaucoma Normally, fluid (aqueous humor) in the eye flows freely through the anterior chamber and exits through the drainage system (trabecular meshwork). If that system is blocked or isn't functioning well, the pressure inside the eye (intraocular pressure) builds, which .