1. A Case Study of Aged Macular Degeneration
(AMD)
Lucia Chen
Final project for the Neurobiology of Everyday Life

2. Macula is is an oval-shaped highly pigmented
yellow spot near the center of the retina of
the human eye. It is often defined as having two
or more layers of ganglion cells.
Near its center is the fovea - a small pit that
contains the largest concentration of
cone cells in the eye and is responsible for
central, high resolution vision.The macula also
contains the parafovea and perifovea.

3. What is macular degeneration?
• Age-related macular degeneration (AMD) is a painless eye condition that generally
leads to the gradual loss of central vision but can sometimes cause a rapid reduction in
vision.
• AMD does not affect the
peripheral vision (outer
vision), which means it will
not cause complete
blindness.
• AMD usually affects both
eyes, but the speed at
which it progresses can
vary from eye to eye.

4. Symptoms
Since the macula contain a large concentration of cone cells, which
responsible for acuity of the vision. Impairment in this area will lead to
symptoms such as:
• loss of visual acuity – the ability to
detect fine detail
• loss of contrast sensitivity – the
ability to see less well-defined
objects
• distortion of central vision –
images, writing or faces can
become distorted in the centre
(this is most commonly associated
with wet AMD)

5. Two Types of AMD
• Dry age-related macular degeneration
The layer of tissue underneath the retina start to thicken as people grow older.This means the
retina can no longer exchange nutrients and waste products as efficiently as it used to.
Waste products start to build up in the retina and form small deposits, known as drusens. A build-
up of drusen, combined with a lack of nutrients, causes the light cells in the macula to become
damaged and stop working.
• Wet age-related macular degeneration
Tiny new blood vessels begin to grow underneath the macula, which form as a misguided attempt by
the body to clear away the waste products from the retina. Unfortunately the blood vessels form
in the wrong place and actually cause more harm than good.They can leak blood and fluid into
the eye, which can cause scarring and damage to the macula.
This then causes the more serious symptoms of wet AMD to develop, such as visual distortion and
blind spots.

6. Case Study
The following study is my father, who developed AMD ten years ago at the age of
57. He had been an electric engineer for more than 30 years. One day he found
his vision was reducing gradually and he went to see the doctor. Everything he
saw was blurred and glasses didn’t help. He was diagnosed of macular
degeneration.The doctor said there’s no particular treatment and recovery is not
very likely. He suffered from depression and anxiety for a few months after the
diagnose. Luckily, he is recovering very well in the recent years.

7. Background
My father was born with a mild form of deuteranopia, he also developed low
myopia when he was a teenager. There’s no evidence shows that physiological
deuteranopia and myopia are related to AMD, although degenerative myopia,
which is characterized by high amount of myopia and progressive deterioration as
the patient grow older is related to myopic macular degeneration.There’s also no
family history showing any hereditary eye diseases. In addition, the paternal side of
my family is subject to high risk of high blood pressure. A few members
developed high blood pressure at middle age and two of my father’s brothers died
of stroke at their 40s and 50s.

8. Symptoms
My father first found he had blurred vision at the center of his vision area when
he was 57. He was diagnosed with AMD and his focus area deteriorated
gradually within two years and he had developed a triangular black spot at the
focus area.The black spot is the blood leak from the abnormal blood vessels. I
suspect that is the wet type of AMD. However, according to my father’s self-
report, the black spot did not always exists. It only appeared occasionally or
when he suffered from sleep deprivation.
He also had myodesopsia, which is caused by a natural change in the consistency
and shape of the vitreous humor that occurs with age. In addition, as the vitreous
humour loses it s shape, it may detach itself from the posterior part of the eye.
During detachment, impulses from the retina may cause the person to see flashes
of light.The vitreous humour’s posterior detachment may also cause part of the
retina to be torn (uncommon), causing blood to leak into the vitreous and the
person will see a sudden appearance of dark dots. Therefore, the black spots he
saw might be a result of myodesopia instead of wet AMD.

9. Treatment
Some doctors suggested him to do laser photocoagulation in order to stop the
bleeding from the blood vessels. However, only about 15 out of 100 cases can be
effectively treated with laser photocoagulation surgery since the surgery works
best when the abnormal blood vessels are clustered close together in a specific
area.
While other doctors suggested him to develop good living habits instead of doing
the surgery, since sealing of the abnormal blood vessels also results in damage of
the ganglion cells at the macula. Ganglion cells resides in the macula responsible for
transmitting visual information to several regions in the thalamus, hypothalamus,
and mesencephalon, or midbrain. Damage of the ganglion cells would affect vision
accuracy permanently.
Eventually, my father chose the conservative treatment. He smoked less and slept
more compared with the earlier days in his life. He ate fish instead of chicken or
red meat in most of his meals. He also took medicine to lower blood pressure and
blood sugar. Luckily he didn’t do laser photocoagulation, as it wouldn’t help in
myodesopsia. Leaking vessels in myodesopia are scattered so surgery will not help.

10. Recovery
He recovered very well since 2008. He showed me some drawings to demonstrate his
progress. The drawing was created a few days ago, he photoshopped the drawings to
demonstrate the fuzziness he encountered in the central focus area (the philtrum) since
the onset of the disease. The drawings only provide a rough depiction of his vision, since
our memory is not always reliable, his current visual experience memory might
compensate his memory of in the past.
The lighter shade on the first drawing represents a fuzziness at the central focus from
2004 to 2008.The second drawing reveals a recovery of the central focus from 2009 to
2012, although the fuzziness had not been totally cleared up yet.
1 2

11. Vision from 2012 - 2014
The third drawing shows
his current vision. He
describes that although
there still seems to be a
very thin layer of mist
covering the central focus
area (the philtrum), his
vision is close to full
recovery.
3

12. Causes of macular degeneration
Exactly what triggers the processes that lead to AMD is unclear, but a
number of things are known to increase the risk factors of developing it.
Age
Family history
Smoking
Gender
Ethnicity
My father
Most cases start developing in people aged
50 or over and then rise sharply with age.
Runs in family
People who smoke are up to four times more likely to
develop AMD than those who have never smoked.
Studies have found rates of AMD are highest in
Caucasians and Chinese people, and lower in black
people.
Women are more likely to develop AMD than men,
but this could simply be because women tend to live
longer than men.
57
No family
history
Yes. (more than
20 years)
Chinese

13. Reflection of the course
The course of Neurobiology of Everyday Life is very useful to my study as I’m a
student major in Psychology and my future career planning would be in cognitive
psychology. After taking this course, I’m able to identify the functions of different
areas in the brain and the cell structure of the brain, an example would be the
function of the visual system.
In vertebrate embryonic development, the eyes and the telencephalon (where
neocortex originate from ) are develop from the front part of the neural tube ,
which is also called lamina terminals.Therefore, the eyes are part of the central
nervous system. Since it is the only part of the CNS that can be viewed directly.
Doctors often check the eyes of the patients to detect hemorrhage or other
neurological disorders. It happens that my father has retinal hemorrhage 10 years
ago, so I study his case in detail after I finished the lecture in week 5: Perception
andVision.
Finally, I have to thank Professor Mason for sharing her grandmother’s case in the
lecture so that I can have more understanding of my father’s disease. I will apply
the knowledge I’ve learnt in this course to my future study in cognitive
psychology.