Laser Eye Surgery | Laser Eye Treatment | LaserEyeSurgery.co.uk » Encyclopedia

Wavefront Technology

admin — Fri, 15 Jan 2010 11:46:28 +0000

The cornea even in its natural state is subject to distortions. In corrective laser eye surgery instead of a single sweep across the eye the cornea is split into small individual squares with each in turn being lasered. The result is reduced post-operative aberrations and therefore a higher standard of vision.

Vitreous Detachment

admin — Fri, 15 Jan 2010 11:45:40 +0000

A state where the vitreous pulls away from the retina. Although harmless in itself can cause a retinal tear or detachment. Most commonly found in the aging eye, high myopes and diabetics.

Vitreous

admin — Fri, 15 Jan 2010 11:44:57 +0000

Jelly like substance that fills the eye between the crystalline lens and the retina.

Vitrectomy

admin — Fri, 15 Jan 2010 11:42:49 +0000

Removal of the vitreous in the event of blood or scar tissue causing cloudiness and therefore reducing the vision. Clear fluid is used to refill the eye.

Visual Field

admin — Fri, 15 Jan 2010 11:41:53 +0000

The arc of vision towards the periphery from the centre when the eye is stationary in a forward position.

Visual Acuity (VA)

admin — Fri, 15 Jan 2010 11:41:26 +0000

Term used to refer to the standard of distance vision achieved at a given distance from the object. 6/6 UK 20/20 US is considered to be normal vision in so much that an object can be seen clearly in the distance (either 6 metres or 20 feet) without compromising the near vision.

The higher the second figure the lower the standard of vision eg. 6/9 means that a normal sighted person with 6/6 vision could see the same object at 9 metres while the person with 6/9 vision would have to move forwards to 6 metres.

Uveitis

admin — Fri, 15 Jan 2010 11:40:13 +0000

Inflammation of the uveal tract (iris, ciliary body and choroid) which can be sudden chronic or recurring. Often linked to rheumatoid arthritis and multiple sclerosis. Symptoms include light sensitivity, tearing, redness, blurred vision and pain. Can often be misdiagnosed.

Ultraviolet

admin — Fri, 15 Jan 2010 11:39:14 +0000

Invisible light. Otherwise known as UV. Rays are shorter than violet and longer than X-Rays thus it lies just beyond the violet end of the spectrum. Exposure to either UVA or UVB is harmful to both the eyes and skin. All standard sunglasses should provide protection and are particularly important when in snow or near water.

Ultrasound B Scan

admin — Fri, 15 Jan 2010 11:38:15 +0000

Used to evaluate visually obstructed tissue by reflecting high frequency waves and converting the electrical impulses into bright spots on a background.

Ultrasound A Scan

admin — Fri, 15 Jan 2010 11:37:49 +0000

Used to asses the length of the eyeball and to differentiate between normal and abnormal tissue by reflecting high frequency waves and converting them into electrical impulses.