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© 2015 ATHENS EYE HOSPITAL - NIKOLAOS PAPAZOGLOU M.D.
The lack of oxygen which is
caused by ischemia, triggers
a stimulus for the production
of a substance (VEGF) which
initiates the production of new
vessels. These new vessels are
unfortunately pathological
and rupture easily causing
hemorrhaging in the vitreous
resulting in the loss of vision.
The extended dysfunction of
the small vessels leads to isch-
emia. Together with ischemia
appear other dysfunctions as
cotton wool spots (that corre-
spond to areas of damage of
nerve fibers).
The microaneurisms can rup-
ture causing microhemorrhag-
ing. The leakage of fluid causes
edema disorientating the retina
and causing severe damage
to sight. The accumulation of
lipids leads to the formation
of yellow deposits which are
called hard exudates.
The increase of sugar in the
blood, leads to the accumula-
tion of toxic substances that
affect the walls of the small
blood vessels increasing the
permeability and decreasing
their strength. This leads to
leakage of fluid and lipids cre-
ating sac-like microaneurisms.
PROLIFERATIVE DIABETIC RETINOPATHY
NON PROLIFERATIVE DIABETIC RETINOPATHY
NORMAL
Retina
Choroid
Sclera
