Macular Degeneration related to the age

The macular degeneration related to the age ( DMLA ) is a Maladie of the Rétine caused by a progressive degeneration of the Macula, central part of the retina, which generally appears starting from the 50 years age, and more frequently as from 65 years, causing an important weakening of the visual capacities, without however destroying them.

The French company of ophthalmology defines it as follows: Together of the lesions of the macular area, degenerative, noninflammatory, acquired, occurring on an eye before normal, appearing after the fifty years age and involving a deterioration of the macular function and central vision . 12% of the population between 65 years and 75 years present a DMLA. It is the main cause of Cécité not corrigeable of the elderly in the western world. In France some 1,3 million people would be reached.

One does not know the precise causes of this disease, and one cannot cure it. The existing treatments only make it possible to slow down its evolution.

History

It was described for the first time in 1874.

Risk factors

There are several:

the age: the risk increases significantly as from 50 years,
the Tabagisme,
family Antécédents: if brother or sister reached, the risk is multiplied by 4. 20% of the cases would be family. Several changes on the genes CFH , LOC387715 , as for that coding the C3 protein of the complement seem, in addition, to involve a faster progression of the disease.
the arterial Hypertension increases the risk of approximately a fifth.
the solar exposure would increase the risk appreciably.
the Overweight and bad dietary habits.

Description of the disease

The disease reaches one or the two eyes. The patient complains about:

Fall of the vision which the patient generally allots to his glasses
Déformation of the images
Impossiblité of reading a word in entirety because of a Scotome

There does not exist any painful phenomenon.

Diagnostic means

the clinical interrogation: to see the macular Syndrome
the Fond of eye, observed using a Ophtalmoscope watch of the modifications of mackled: Drusen (in the form of small spots) hearths of hypo or hyperpigmentations…
the Angiographie with fluorescein highlights the néovaisseaux ones (NV), or its consequences (DSR, hemorrhage) and characterizes them (occult or visible)

Néovaisseaux " visibles" , are those highlighted by the angiogaphy at fluorescein, of the néovaisseaux " occultes" , are badly highlighted by this examination, but identified well by the angio the mixed ICG, and forms.

Various types

There exist two forms: the atrophic form and the exsudative form. They can all two coexist on the same eye.

The atrophic form " sèche"

The atrophic form (or " sèche") corresponds to an atrophy of mackled. There exist only preventive medications. This form repésente 50% of the DMLA and the evolution towards the degradation of the vision is, in general, slow. The retinal atrophy saves a long time the center of mackled. Neovaisseaux choroidiens can appear during the evolution. The affection is often bilateral.

The exsudative form " humide"

The exsudative form (or " humide") corresponds to the appearance of néovaisseaux choroïdiens (NVC). The latter are is subepithelial (thus developing under the pigmentary epithelium) and thus known as " occultes" , that is to say know-epithelial and thus known as " visibles". A certain number of atrophic forms evolve/move in exsudative form. The evolution is faster than in the dry forms. In certain cases, treatments allow, as well as possible to stabilize the disease,

Early stages of the macular degeneration

That is to say a hypopigmentation of the retina associated with small white spots on the retina (Drusen). It is rather rare 3,5% between 55 and 64 years (on the basis of patient with dégenerance macular?). There exists a small risk of formations of néo-vessels in 4,7% of the cases.

That is to say a hyperpigmentation due to an accumulation of pigments, even rarer 3,7% between 35 and 64 years (on the basis of patient with dégenerance macular?) This pigmentation is a secondary reaction to any repair of the junction choriorétinienne.

Both are visible by making a retina or a angiography and their appearance require an increased ophthalmologic monitoring.

Treatment

There is no treatment currently known (curative or preventive) concerning the DMLA of form atrophique.
The treatment of the lesions extrafovéolaires of the DMLA néovasculaire is photocoagulation by laser argon or krypton, which once stabilizes them on deux.
The treatment of reference of the lesions rétrofovéolaires of the DMLA néovasculaire is dynamic phototherapy. It does not improve the vision but stabilizes the visual loss, at half of the patients. It consists of the intravenous injection of vertéporfine , photosensitizing, followed application of a red light per laser on the zone to treat.

Preventive medication by supplementation in antioxydants (vitamins, zinc…) proved to be without shown effectiveness.

The use of monoclonal antibodies recombining, targeted against the growth factor endothéliale of the type has, was proposed with certain an effectiveness to slow down the evolution of the exhudative form of the disease. They are primarily the Pegabtamib of sodium, the Ranibizumab and the Bevacizumab. The obstacle remains about it their cost and their mode of administration (regular injections in the eye by way intra-vitréenne).
The bevacizumab tends to being largely used in certain countries, even if there do not exist less direct studies proving its effectiveness, and this, primarily because of its price réduit.
The ranibizumab is more effective than the vertéporfine but with taken sometimes serious undesirable effects (inflammatory and infectious risks local, cerebral vascular accident), justifying its use in 2nd intention, i.e. after failure of a first treatment by vertéporfine

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