Hair Transplant Basics:
Method of Harvesting Grafts
There are four common methods of harvesting donor grafts. The original
method, devised by Dr. Orentreich, used a hand punch to cut single grafts
4-mm in size that could contain up to 30 or more hairs. Each punch hole
was separated by small islands of skin. Besides producing very large grafts,
there was hair wastage around the periphery, due to transection and improper
angling of the punch. This method is now rarely used. A second method
utilizes a mechanical punch held in a small hand engine to core out a
number of round grafts of known size. The punch turns at very high speeds;
the torque and heat energy generated by this method will damage the donor
grafts. The donor grafts obtained by the punch methods can be made into
minigrafts by halving or quartering them. The donor area can then be closed
by suturing or can be left open. If the donor sites are not closed, they
develop significant scars. Most doctors have abandoned these techniques.
The third method uses multiple, parallel scalpels attached together on
a handle, called a multi-bladed knife. Multiple thin strips of hair-bearing
donor skin are removed simultaneously and then grafts of the desired size
are cut from the thin strips of tissue produced by the multi-bladed knife.
Using a scalpel does not produce any torque or heat energy; therefore,
no heat or torque damage to the grafts can occur. This method is quick
and simple and still quite popular. Unfortunately, this method can cause
extensive damage to the donor tissue, as it is impossible to line up the
multiple blades parallel to the hair follicles. Because of this there
is unacceptable cutting of individual follicles (transection) and breaking
up of naturally occurring follicular units.
In a fourth method, called single strip harvesting, the donor tissue is
removed as a single strip. The great advantage of this method is that
the tissue is removed from the scalp with the minimal amount of "blind"
cutting. The only blind cutting is the single incision around the periphery
of the donor strip as it is removed. All further dissection can be then
performed by direct visualization using a dissecting stereomicroscope.
This keeps potential damage to follicles at an absolute minimum and allows
preservation of intact naturally occurring follicular units. In order
to perform Follicular Unit Transplantation, single strip harvesting and
stereo-microscopic dissectAppearance of the Donor Area
Unless the back and side hair is extremely short, the donor area will
be covered by hair and will be unnoticeable after surgery. All donor "harvests"
result in a scar, but if done properly, the scars may become, for all
practical purposes, virtually invisible. Not only is it important for
the scar to be closed meticulously, but also the scar must be placed in
the proper position, in the mid-portion of the donor area. Scars that
are place too low have an increased risk of stretching from the movement
of the neck muscles. Scars that are placed very high run the risk of being
visible if there is extensive balding. In addition, the hair that is obtained
from these high incisions may not be permanent.
Re-harvesting the same area is important to keep visible scaring to a
minimum and to keep the donor scar in the mid-portion of the permanent
zone. Some doctors harvest a new area for each surgery. When many surgeries
are done, these patients have a stepladder appearance of the back of the
scalp from the multiple scars. Each scar distorts the hair shafts in either
side of the adjacent skin. This distortion occurs because scars tend to
contract. When contraction occurs, the microscopic structures around the
scar are pulled. If different donor sites are chosen for each hair transplant
procedure, the total area for distortion of the hair follicles becomes
quite extensive. Such distortions can affect the surgeon's ability to
maximize the donor hair supply for more extensive hair transplant restorations
and often limit the surgeon's ability to keep the donor site undetectable.
The following photographs demonstrate the contrast between extensive scarring
associated with multiple procedures, when donor hair is taken from different
areas for each procedure and a properly placed scar repeated from the
same location.
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