The macula is responsible for our most highly focused vision: central vision.
The macula is a small yellowish area at the center of the retina, it receives its yellow color from the pigmented antioxidants lutein, zeaxanthin, and meso-zeaxanthin.
Meso-zeaxanthin is most highly concentrated in the epicenter of the macula, zeaxanthin in the mid-periphery, and lutein in the periphery of the retina. The macula’s yellow color absorbs blue to UV light and behaves like protective sunglasses against damaging UV light.
Macular Degeneration (AMD, ARMD) is the gradual breakdown of the macula cells. Such deterioration weakens your ability to read, write, drive, and recognize faces. Peripheral, or side vision isn’t damaged.
If there are any positives to macular degeneration, it is that, treated early-on, it is very responsive to treatment.
The development and progression of macular degeneration rests upon the occurrence of the following pathological changes in the eye.
Oxidative stress – the imbalance between free radicals and protective antioxidants. The retina is especially vulnerable to stress from free radicals. Inability of the retina tissue to have enough oxygen available leads to deterioration of the pigmented layer which protects the retina from UV and blue light damage.
Poor Blood Flow can lead to Angiogenesis – lack of blood flow oxygen leads to development of new extra blood vessels which distort the retina and can rupture and bleed.
Apoptosis – cell death is a natural phenomenon in the body as worn and damaged tissue is removed and replaced. However, in the retina excessive cell death is closely tied to oxidative stress.
Inflammation – the inflammatory response is the body’s attempt to rescue tissue from cell injury. Proteins which are responsible for the immune results are among the constituents of drusen deposits in the retina as AMD develops.
Retinitis pigmentosa comprises a group of inherited disorders, such as Leber’s, in which the rods and cones that make up the photoreceptor cells in the retina are dysfunctional, due to genetic mutations.
About half of retinitis pigmentosa (RP) cases appear to be isolated with no previous family history.
Retinitis pigmentosa is a progressive degenerative disorder of the photoreceptors and/or retinal pigmented epithelium (RPE) that can cause a profound loss of vision. The vast majority of patients are over 45 years old, although the symptoms of RP often appear in childhood, causing difficulty in seeing at night, and requiring longer time in adjusting from dark to light.
Retinitis pigmentosa primarily affects the side (peripheral) vision due to deterioration of the rod photoreceptors, but in later life it can affect the cones, rarely resulting in total blindness, but possibly leading to the state of “legal blindness” by age 40. Most people retain central vision with restricted side vision into their 50s. This is referred to as tunnel vision.