The Cosmetic Significance of Follicular
Units Vs. Small Minigrafts
All forms of hair restoration surgery involve redistribution
of existing hair follicles. No form of surgery will
provide more hair follicles than those that currently
exist. Therefore the success of hair restoration surgery
for any patient depends on optimizing the cosmetic redistribution
of an inherently limited number of hairs. The goal has
been to find techniques that allow us to achieve both
naturalness and the appearance of density within the
constraints of this limited amount of hair. In an effort
to improve naturalness the trend has been to use smaller
grafts and this has ultimately led to the "follicular
unit" graft and total "follicular unit"
grafting. Most experienced practitioners of hair restoration
surgery agree that the hairline should be a "feathered"
zone, with deliberate irregularities, created using
several hundreds of these 1-2 hair follicular units.
However, there continues to be active debate over the
optimal method of hair transplantation in the central
area behind the hairline. Some believe that density
cannot be achieved using only 1-3 hair follicular units
in this area. They feel that slightly larger 3-5 hair
minigrafts "cut to size" need to be placed
in this central area where they typically will not be
scrutinized as closely for naturalness, but where they
will contribute to an overall increased number of hairs
to achieve the "illusion of density".
With respect to density, in many cases the size of
the scalp area needing coverage is larger than the remaining
donor area. Attempting to achieve "equivalent"
density would rapidly outstrip the available donor follicles.
However, achieving identical density is not necessary
to obtain an excellent cosmetic result as the "illusion
of density" can be achieved with far fewer follicles
than existed pre-hair loss. The resulting cosmetic appearance
is an optical illusion, the appearance of density rather
than actual density.
With respect to naturalness, if the general appearance
of the hair does not reveal an unusual pattern of individual
hairs or groupings of hairs – under any circumstance
(i.e.wind, rain, water sports etc) and at any level
of inspection, the appearance of naturalness has been
achieved, and with fewer than "normal" numbers
The challenge becomes how to redistribute this precious
limited commodity with the least amount of waste and
a high degree of follicle survival, while maintaining
the most uniformly cosmetic results. The debate, in
essence, centers on the comparative advantages and disadvantages
of 1-3 hair "follicular units" vs. 3-5 hair
minigrafts "cut to size, " with respect to
achieving naturalness and density in the central area
behind the hairline.
"Follicular units" are prepared by isolating
naturally occurring groupings of 1-3 hairs and trimming
them of as much epithelium and extra tissue as safely
possible. The minimal amount of epithelium left on these
grafts limits the "pitting" that sometime
occurs when grafts are unintentionally placed too deep.
Because "follicular unit" grafts are smaller
than untrimmed grafts with equivalent amounts of hair
they can fit into small microincisions placed very close
together. These natural groupings combined with their
ability to be placed in close proximity to one another
closely mimic nature, thereby creating the highest degree
of ‘naturalness’ on a consistent basis.
They can be undetectable under close examination.
The controversy over using only follicular units in
the central area has to do with their ability to produce
the" appearance of density". Density is a
function of the number of hairs in an area, not the
size of the graft. Above a certain threshold, the same
amount of hair should produce the same appearance of
density independent of the type of graft used. The problem
with follicular units is not that density can’t
be produced but that density is more difficult to produce.
A number of factors make the successful use of follicular
units more difficult.
First, due to their small size, follicular units are
more fragile than larger grafts. Placing a large number
of these very small grafts in closely approximated microincisions
is technically difficult, increasing the risk of follicular
injury and subsequent poor growth. However, with experience,
skill, and proper placing techniques this problem can
Waste is another problem that can occur when using
"follicular units". Waste is distinctly different
from follicular injury and poor growth. The term "waste"
refers to hair follicles that are lost or discarded
during the trimming process. A given area of donor tissue
has a finite number of hair follicles. Hairs transected
during the donor harvesting and dissection process have
the potential of being discarded. Intrinsically, the
extensive trimming necessary to produce good quality
follicular units increases this risk of waste. Recent
reports state the increased potential for waste associated
with cutting follicular units can be nearly eliminated
with skillful use of the stereoscopic dissecting microscope.
The degree of waste is less with small minigrafts "cut
to size" because these grafts use all of the donor
tissue including the transected hairs. The yield and
quality of the transected hairs found in small minigrafts
has not been established
Finally, because there are less hairs per graft, it
takes a larger number of "follicular units"
to move the same amount of hair to an area as with larger
grafts. This ultimately makes the procedure more labor
intensive, time consuming and costly.
Density can be produced when using follicular units
if the above problems are addressed. However it takes
a lot more effort, time, and skill. The question is:
Is the increased degree of naturalness achievable with
"follicular units" clinically significant
in the central area where grafts are less scrutinized?
Is this degree of increased naturalness worth the risk
and increased effort necessary to produce density with
this type of graft?
SMALL MINIGRAFTS "CUT TO SIZE"
Small minigrafts " cut to size contain an average
of 3-5 hairs per graft. The size of the graft is determined
by the donor density. Grafts can be cut thin and flat
for slits, or more rectangular for punches. It is my
opinion that the most consistently natural 3-5 hair
minigrafts are thin flat grafts for slits because the
hairs line up linearly and there is less chance of compression.
If done properly a thin, flat minigraft placed in appropriate
sized slits can look like 2 follicular units lined up
behind each. These minigrafts, when compared to "follicular
units", are less susceptible to trauma and poor
growth. Also, because not each follicular grouping is
being separated, there are fewer cuts with the dissecting
knife and the risk of transection and waste is inherently
less. Finally, since the same numbers of hair can be
transplanted with fewer grafts, this technique is less
labor intensive, time consuming and costly.
The disadvantage of 3-5 hair minigrafts "cut to
size" is the increased potential to be less natural
and look "grafty". These grafts have an increased
risk for compression, especially if the grafts are not
cut thin and flat or are placed in too small a slit.
This problem is more likely to occur in patients with
high density where grafts cut to size may unintentionally
contain more than 5 hairs. Because these grafts contain
a small piece of epithelium, there is an increased chance
of pitting. If this small piece of epithelium is pushed
below the layer of stratum cornea and stays there, the
body will try to incorporate or encyst it. The former
will result in pitting; the latter in a permanent annoying
bump possibly associated with inflammation and foreign
body reaction. The most effective way to avoid pitting
is to make the incision only as deep as necessary to
incorporate the graft follicle up to, but not including
In conclusion, it is possible to achieve the appearance
of naturalness and density on a consistent basis with
natural follicular groupings called "follicular
units". This method requires greater numbers of
grafts and technical skill in order to achieve cosmetic
density. But once the technical skill to perform this
technique is achieved the look is invariably natural.
The question is: Is the increased degree and consistency
of naturalness produced with follicular units worth
the effort and risk necessary to achieve the appearance
of density, especially in the central area were grafts
are less scrutinized.
Mini grafting in the central area using 3-5 hair grafts
"cut to size" offers the practitioner and
patient a faster, slightly more economical way to achieve
coverage, and if performed skillfully can achieve nearly
the same degree of naturalness as single follicular
groupings. However, the caveats are several, and when
not observed, the results are a step down from the Mercedes
Benz of grafts, the follicular unit.