0:00
Good day,
my name is Robert Mullins,
and I'm a professor
of Ophthalmology
and Visual Sciences
at the University of Iowa.
Today we're going to talk
about the changes
that occur in the choroid
in aging and in macular disease.
0:15
The choroid has some normal
physiological changes
that occur during aging
that are differentiated
from those
that occur in diseases,
like macular degeneration.
Some of the same events
that occur during normal aging,
however, can occur
to a more profound
extent in diseases,
like age-related
macular degeneration or AMD.
0:36
Age-related
macular degeneration
is a common form of blindness
that affects millions
in the Western world.
And as its name implies,
it is an age-related disease.
It's normally not seen
in individuals
under the age of 55 or 60.
It affects the macular
specific region of the retina
that's responsible
for visual acuity.
The macula itself is about
only the size
of a button on one's shirt,
but in spite of the fact
that it's a small portion
of the retina,
it's responsible for
most of our daily vision.
And it's a degenerative disease
in which the photoreceptor cells
will eventually succumb to loss
through one of
several mechanisms.
We don't completely understand
the pathogenesis
of this disease.
We do know that
there are different phenotypes
or what might be considered
stages including early AMD,
neovascular AMD,
and atrophic AMD.
And these stages
are characterized
by structural feature
called drusen.
1:35
The next few slides will compare
the fundus appearance
on the left,
with the histological
appearance on the right,
of different disease types
in AMD.
And I should say
that the sections
are not collected
from the same photograph
in each case,
as the fundus picture.
However, they do give
a good comparison
of what the histology
looks like in each case.
First is a normal eye,
you can see
the retinal circulation.
The collateral circulation
is masked largely by the RPE.
And histologically,
the ganglion cell layer,
the inner nuclear layer,
the outer nuclear layer
are present.
The RPE is present
as a continuous layer,
and the choriocapillaris,
you can see
as these white openings
that correspond to healthy
viable choriocapillaris vessels.
