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Hair Loss in Men
1) Causes of Hair
Loss
A) Localized Hair
Loss
B) Male Pattern
Baldness
1) Genes
2) Hormones
3)
Age
2) Assessing Hair
Loss
Norwood
Classification of
Hair Loss
A) Regular Norwood
Classes
B) Type A Variant
Norwood Classes
3) How much hair do
I need?
1)Causes of Hair
Loss
To understand the
different types of
hair loss in women,
and their
management, it is
helpful to divide
the patterns into 2
categories:
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A)Localized Hair
Loss
Localized hair loss
may be sub-divided
into scarring and
non-scarring types.
Alopecia Areata is a
genetic, auto-immune
disease that
typifies the
non-scarring type.
It manifests itself
with the sudden
onset of round
patches of hair loss
associated with
normal skin and can
be treated with
local injections of
Corticosteroids.
Hair Transplantation
is not helpful for
this type of Hair
Loss.
Alopeci Areata
Scarring Alopecia
can be caused by a
variety of medical
or dermatologic
conditions such as
Lupus and Lichen
Planus, local
radiation therapy,
injuries, or from
local medical
problems. Once the
active process of
Alopecia have been
cured, It is usually
amenable to Hair
Transplantation.
Scarring Alopecia
Localized hair loss
that occurs around
the hairline after
face-lift surgery
may be permanent as
can Traction
Alopecia, the hair
loss that occurs
with constant
tugging on the hair.
Both of these
conditions can be
treated with Hair
Transplantation.
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B)Male Pattern
Baldness
The most common type
of baldness in men
is called Male
Pattern Baldness or
more scientifically,
Androgenetic
Alopecia. In
Androgenetic
Alopecia, hair
follicles that are
producing healthy,
terminal hairs begin
to produce thinner,
shorter, more
brittle hairs with
weaker shafts (this
process is called
Miniaturization and
the hairs involved
are called
Miniaturized hairs).
Eventually, these
follicles produce
only fine, almost
invisible, short,
vellus hairs, or
they may die out
altogether.
Androgenetic hair
loss is caused by
the effects of male
hormones on
genetically
susceptible hair
follicles. It is
related to three
interdependent
factors:
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1)Genes
Common baldness
cannot occur without
the presence of
specific inherited
genes. These genes
can be passed on by
either parent. A
gene is a single bit
of chemically
encoded hereditary
instruction that is
located on a
chromosome and
actually represents
a tiny segment of
DNA. Chromosomes
occur in pairs
(humans have 23
pairs), and every
individual gets one
set of chromosomes
from each parent.
The genetics of
androgenetic
alopecia is
complicated and hair
loss is now felt to
involve more than
one gene. When
several genes govern
a trait, it is
called polygenic.
Genes that are
located on the X or
Y-chromosomes are
call sex-linked.
Genes on the other
22 pairs of
chromosomes are
called autosomal. It
is felt that the
genes governing
common baldness are
autosomal. This
means that the
baldness trait can
be inherited from
the mother's side of
the family or the
father's side. The
commonly held notion
that baldness comes
only from the
mother's side of the
family is incorrect,
although for reasons
not fully
understood, the
predisposition
inherited from an
affected mother is
of slightly greater
importance than that
inherited from an
affected father.
The term, "dominant"
means that only one
gene of a pair is
needed for the trait
to show up in the
individual. A
"recessive" gene
means that both
genes need to be
present in order for
the trait to be
expressed. The genes
involved in
androgenetic
alopecia are felt to
be dominant.
Just because a
person has the genes
for baldness,
doesn't mean the
trait will manifest
itself. The ability
of a gene to affect
one's
characteristics,
i.e. be visible in a
particular
individual, is
called "expresivity".
Gene expression is
related to a number
of factors, the
major ones being
hormones and age,
although stress and
other factors can
play a role. To put
it simply, a man
whose father and
uncles are severely
bald may have
minimal hair loss
himself, either
because the baldness
genes have not been
passed on or because
the expression of
the baldness gene
that he did inherit
is limited.
It is of interest
that, to date, none
of the genes for
male pattern
baldness have been
identified. This
suggests that any
kind of genetic
engineering to
prevent common
baldness is still
many years away.
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2)Hormones
Hormones are
biochemical
substances that are
made in various
glands throughout
the body. These
glands secrete their
products directly
into the bloodstream
so that the chemical
they make is spread
throughout the body.
These chemicals are
very powerful; only
minute amounts of
them have profound
effects upon the
body.
The major male sex
hormone is called
testosterone.
Testosterone and
other related
hormones that have
masculinizing
effects are made
primarily in the
testicles,
therefore, the
hormonal levels that
are seen in adults
do not reached
significant levels
until the testicles
develop and enlarge
during puberty. In
fact, these same
hormones are the
cause of many of the
changes that occur
in puberty; change
in the voice, growth
of the beard and
mustache,
development of an
adult aroma in the
sweat, change in the
muscular
development, and
change in the basic
body shape.
These same hormones
that cause acne and
beard growth can
also signal the
beginning of
baldness. The
presence of
androgens;
testosterone, and
its related hormone
DHT, cause some
follicles to regress
and die. In women,
hormones with
androgenic activity
cause hair loss as
well. In addition to
the testicles, the
adrenal glands
located above each
of our kidneys,
produce androgenic
hormones, and this
would be similar in
both sexes. In
females, the ovaries
are an additional
source of hormones
that can affect
hair.
The specific
relationship between
testosterone and
hormonally induced
hair loss was
discovered by a
psychiatrist early
in this century. At
that time,
castration was
commonly performed
on patients with
certain types of
mental illness. The
rationale behind
this procedure was
that it was believed
to be a treatment
for mental illness
at a time when there
were no other forms
of real treatment.
Castration seemed to
have a calming
effect upon many
patients and
castration reduced
the sex drive of
patients who had no
outlet for their
desires. The doctor
noted that the
identical twin
brother of one
patient was
profoundly bald
while the mentally
ill twin had a full
head of hair. The
doctor decided to
determine the effect
of treating his
patient with
testosterone, which
had recently become
available in a
purified form. He
injected his
patient, the hairy
twin, with
testosterone to see
what would happen.
Within weeks, the
hairy twin began to
lose all but his
wreath of permanent
hair, just like his
normal twin. The
doctor, then,
stopped giving the
testosterone to see
whether the process
would be reversed,
but the balding
process continued
and his patient
never regained his
full head of hair.
It was apparent to
him that eliminating
testosterone will
slow, or stop,
further hair loss
once it has begun,
but it will not
revive any dead
follicles.
The hormone felt to
be directly involved
in androgenetic
alopecia is actually
Dihydrotestosterone
(DHT) rather than
testosterone. DHT is
formed by the action
of the enzyme 5-a
reductase on
testosterone. DHT
acts by binding to
special receptor
sites on the cells
of the hair
follicles to cause
the specific changes
associated with
balding. Among other
effects, DHT
decreases the length
of the anagen
(growing) cycle, and
increases the
telogen (resting)
phase, so that with
each new cycle the
hair shaft becomes
progressively
smaller.
It is interesting
that testosterone
effects axillary and
pubic hair, whereas
DHT effects beard
growth, patterned
baldness and the
appearance of hair
in the nose and ears
(something that
older men
experience). Scalp
hair growth,
however, is not
androgen dependent,
only scalp hair loss
depends on
androgens.
In men, 5-a
reductase activity
is higher in the
balding area. This
is the enzyme that
is inhibited by the
hair loss medication
finasteride. Women
have ½ the amount of
5-a reductase
overall as compared
to men, but have
higher levels of the
enzyme aromatase,
especially in their
frontal hairline.
Aromatase decreases
the formation of DHT,
and its presence in
women may help to
explain why the
presentation of hair
loss in women is
different than in
males.
One should keep in
mind that the
presence of the
necessary genes and
hormones are not, in
themselves,
sufficient to cause
baldness. The
reaction also
requires time of
exposure of
susceptible hair
follicles to the
hormone for hair
loss to begin. The
time required for
this to start varies
from one individual
to another and is
related to a
person's genetic
expression and to
the levels of
testosterone in his
bloodstream.
There is another
time factor that is
poorly understood.
Hair loss does not
occur all at once
nor in a steady,
straight-line
progression. Hair
loss is cyclical.
People who are
losing their hair
experience
alternating periods
of slow and rapid
hair loss and even
stability. Many of
the factors that
cause the rate of
loss to speed up or
slow down are
unknown.
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3)Age
The presence of the
necessary genes and
hormones are not
alone sufficient to
cause baldness. Even
after a person has
reached puberty,
susceptible hair
follicles must
continually be
exposed to the
hormone over a
period of time for
hair loss to occur.
The age at which
these effects
finally manifest
themselves varies
from one individual
to another and is
related to a
person's genetic
composition and to
the levels of
testosterone in the
bloodstream.
Hair loss does not
occur all at once,
nor in a steady,
straight-line
progression. People
who are losing their
hair experience
alternating periods
of slow and rapid
hair loss and even
stability. Many of
the factors that
cause the rate of
loss to speed up or
slow down are
unknown, but we do
know that with age,
a person's total
hair volume will
decrease.
Even when there is
no predisposition to
genetic balding, as
a patient ages, some
hairs randomly begin
to miniaturize
(shrink in length
and width) in each
follicular unit. As
a result, each group
will contain both of
full terminal hairs
and miniaturized
hairs (similar to
the very fine hairs
that occur on the
rest of the body and
are clinically
insignificant)
making the area look
less full.
Eventually, the
miniaturized hairs
are lost, and the
actual follicular
units are reduced in
number. In all adult
patients, the entire
scalp undergoes this
aging process so
that even the donor
zone is not truly
permanent, but will
gradually thin, to
some degree, over
time. Fortunately,
in most people, the
donor zone retains
enough permanent
hair that hair
transplantation is a
viable procedure
even for a patient
well into his 70's.
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2)Assessing Hair
Loss
The first step in
making a rational
assessment of the
extent of your hair
loss, is to compare
your present
hairline with the
hairline on a
photograph taken a
few years ago. This
will give you an
approximate idea of
how much hair loss
has occurred and the
rapidity of the
process. The unknown
factor for most men
is the extent of
hair loss in the
crown area. Looking
in a mirror is one
way to appraise the
loss at the back of
your head. The best
way to accurately
assess the hair loss
in this area is to
have a friend take a
Polaroid photo of
the back of your
head. For an
accurate reading,
the picture must be
taken with a flash.
Another way is to
ask your barber or
hairdresser.
A visit to Dr.
Vafaei who is
specialist in hair
restoration is a
worthwhile step. A
thorough history and
examination of the
scalp can reveal the
extent and trend of
the hair loss
process. With the
use of the Hair
Densitometer, a
special magnifying
apparatus, Dr.
Vafaei can measure
the actual degree of
hair loss in various
areas of the scalp.
This has the
advantage of
establishing a
baseline from which
the hair loss can be
graded over time. If
you decide to treat
the process with
minoxidil, a repeat
examination in 6-12
months may show the
effectiveness of the
treatment. Careful
assessment of the
hair loss process is
critical to accurate
prediction of the
rate and extent of
hair loss.
The scientific way
to assess your
degree of baldness
is to compare your
pattern with the
standard patterns
described by Dr.
O'Tar Norwood. They
depict the most
common
configurations of
male pattern
baldness. There are
seven grades of hair
loss in the main
series and five
grades of a
variation called the
"A" series.
Comparing your own
front and back with
these diagrams can
tell you where you
stand now.
Discussion with Dr.
Vafaei can give you
some idea of what is
likely to be in your
future.
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Dr. O'Tar Norwood
Norwood
Classification of
Hair Loss
In 1975, a
dermatologist and
hair transplant
surgeon, Dr. O'Tar
Norwood, building
upon the earlier
work of Hamilton,
developed a
classification of
male pattern hair
loss that is widely
used today. He
divided androgenetic
hair loss in men
into two common
patterns: the
Regular Type,
characterized by
hair loss that
begins in two
different areas (at
the temples and in
the crown) and that
gradually merge into
one; and the less
common Type A, that
is characterized by
"front-to-back" hair
loss. Hair loss that
is not genetic in
origin usually
follows a different
pattern.
Some women also lose
hair according to
the pattern
described by
Norwood, but more
commonly have a
diffuse (thin all
over), rather than
patterned variety
(please see
Hair Loss in Women).
Hair loss tends to
progress over the
years, although the
rate can vary
dramatically from
person to person and
the rate of loss can
vary significantly
over time. For
example, a man may
loose hair rapidly
in his early 40's
and then stabilize
for many years, not
showing a
significant amount
of additional hair
loss until his 60's.
People who become
extensively bald
usually, but not
always, show a
significant amount
of hair loss in
their 20's.
In general, the
pattern of one's
hair loss follows
the specific type
first presented. For
example, a person
who begins as a
Class 3 usually
evolves into a Class
4, then a Class 5,
etc.. A Class 3a
becomes a Class 4a
and then a Class 5a.
Less commonly a
Class 2 may thin
diffusely and
directly evolve into
a Class 6 or 7. We
call this later
process Diffuse
Patterned Alopecia.
Look over the
following diagrams
and their
explanations to see
if you can recognize
your pattern or the
pattern of hair loss
of any male member
of your father's or
mother's side of the
family. The patterns
you see in your
older relatives may
become your pattern
since heredity plays
an important role in
androgenetic
baldness. It is
important to note
the age at which the
family member
reached a specific
pattern. For
example, if your
father is totally
bald, but lost all
of his hair in his
twenties, and you
are 35 with a full
head of hair, his
pattern has little
relevance to
predicting your
future loss.
Once you have
identified your
Norwood Class, view
our
photo galleries
to view before and
after photos of
actual patients.
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A)Regular Norwood
Classes
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B)Type A Variant
Norwood Classes
A)
Frontal recession keeps advancing
backwards
B)
Single area of balding
C)
Eventual extent of balding tends to be
more limited than in
Regular classes
Entire frontal
hairline recedes
Hair loss moves past
this "mid-coronal"
line
Hair loss extends
towards the vertex
Back part of bald
area is narrower
than in the regular
Norwood VI
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3)How much hair do I
need?
Over the past few
years, we have tried
to put a number on
the amount of hair
and grafts any given
person might need.
As we have gained
experience, we have
found that our
patients want more
hair than we had
believed. At our
center, patient
procedures are
planned to ensure
natural looking
results after each
session. However,
some of our patients
elect to undergo
further sessions to
further enhance
their appearance. A
recurring question
is how much hair
does Dr. Vafaei
recommend? The
number of grafts
recommended is
highly dependent on
information we would
gather during a
private consultation
with you, as well as
the characteristics
of the
hair-coarseness,
texture, etc.
The total number of
follicular units
generally
transplanted in the
first session for
specific Norwood
classifications are
listed in the table
below. In general,
the higher the donor
density, the greater
the number of hairs
each follicular unit
will contain. With
low donor density,
little scalp laxity
or poor hair
characteristics,
these numbers may
not be achievable.
The number of grafts
that can be
harvested for any
individual is
limited by the
laxity of the scalp
and the density of
the hair. In some
individuals, it will
be impossible to
safely move 5000 or
more grafts over the
individual's
lifetime, while in
other individuals,
the number of grafts
can reach
significantly above
7000.
|
Norwood
Class |
Follicular
Units |
Total Units
With Crown* |
|
3 |
800-1000 + |
** - |
|
3 Vertex |
800-1000+ |
1100-1300+ |
|
3A |
1300-1600+ |
- |
|
4 |
1100-1400+ |
1500-1800+ |
|
4A |
1700-2100+ |
- |
|
5 |
1500-1800+ |
1900-2500+ |
|
5A |
2200-3000+ |
- |
|
6 |
2000-3200+ |
2800-3800+ |
|
7 |
2000-3500+ |
|
 |
 |
|
Before |
After |
Befor Hair
Transplantation
Surgery
After Hair
Transplantation
Surgery
Befor Hair
Transplantation
Surgery
After Hair
Transplantation
Surgery
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