الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
r.~cu1ar degenerations can be classified into two
big groups:-
1- Heredo macular degenerations:
A genetically determined group of diseases which
run in families include:-
;~) PrirrtJryretinal degeneI’8.tionjwhere the neuroepithelium
of the retina is the seat of pe,thology
with no evidence of a primary cause in the
choroid. Visual affection develops at various
ages according to the type of the disease. Eye
affection occurs without any a asocLated degeneration
of the C.N.S. such diseases are called collectively,
the tapeto-Retinal Dystrophies.
~) Primary choroidal dystrouhy, where choroidal
elements (choriocapillaris) together with retinal
elements (neuro-and pigment epithelium) are
the seat of the pathology.
Sye aff~ction may occur alone as in sorsby’s
pseudo- inflac)8.t’Jr~,mccuLar atrophy or with
other cerebral and systemic ll13,nifestationsas
lipidosis.
2- Secondary chorioretinal degenerations:
Macular degeneration results from the disturbance
of retinal nutrition secondary to choroidal affection.
In general, the choroid is affected either by
sclerosis of its vessels or by thickning of the inter
capillary connective tissue. Subsequently, !ruch’s
membrane and hence, the chorioretinal barrier and
retinal nutrition are affected.
Senile scler~sis of the choroid may result in
macular degeneration, the condition is either dryas
in senile macular degeneration or exudative as in
senile disciform macular degenerations. Juvenile
disciform macular degeneration is a similar condition
to the senile type but of a different etiology
and better prognosis. In degenerative axial myopia,
chorioretinal atrophy results in macular degeneration
and other retinal degenerations. As the macula is
avascular. the persistant aedema may lead to cystoid
macular degeneralian.
In retinal hypoxia. lipid masses may be deposited
around the macula forming a ring; this ring
with macular degeneration constitutes what is called
circinate macula~ degeneration.
Recently, the abuse of photocoagulation is a
new cause of macular degeneration.