What is meant by follicular unit graft size? Many illustrations of hair follicles show a cross sectional diagram consisting of a single hair. But if you have done your research on modern FUE hair transplant techniques, you have probably read that today’s grafts are based on the concept of follicular units. These are naturally occurring clusters of hair follicles.

If you look at photographs of these structures, you will notice that the groupings are encased in what is referred to as a dermal root sheath.

Each hair follicle cluster may consist of anywhere from one , four or even higher numbers of hair. These are referred to as:

single follicle/ graft
double follicle/graft
tertiaries/ triple follicle or graft
quadruple follicle

With more hair follicles , the diameter of the entire follicular unit graft becomes larger. And the size of the grafts would affect the size of the punch needed. For example, larger diameter instruments would be needed for the bigger grafts to avoid damaging the structure. Therefore, it is not uncommon for more than one punch size to be used on the same patient.

How Different Types of Follicular Unit Graft Sizes Are Used in A Hair Transplantation

Throughout the head, different sized follicular units comprise the overall patterning of growth patterns within different regions. Along the outer edge of the hairline, single haired grafts provide a soft and feathery quality. The use of wrong sized grafts (e.g. tertiaries etc.) is what creates a pluggy appearance which most patients are wary of and try to avoid. It should be noted that size of graft varies with location of the scalp or body from which the graft is derived. tertiaries in the nape area would still look finer relative to tertiaries from the middle of the back of the head

Beyond this margin, clusters of follicles progressively increase. Doubles are then used behind the singles. And tertiaries and quadruples are inserted beyond this point to provide the necessary volume in regions such as:

posterior frontal scalp
midscalp
vertex

The creation of a natural looking density will depend to a certain extent on choosing the appropriate sized follicular unit.

Follicular Unit Size As A Possible Explanation For Partial FUE

There is much discussion around a procedure that is being referred to as pFUE or partial FUE. Some people believe that new hair structures are formed by removing tissue from the base of the hair follicle.

A tiny Follicular Unit Extraction punch is used to perform an extraction on a donor hair. And then it is inserted into the recipient area where it seems that a new hair grows.

To the individual who understands a hair follicle to be a single structure which grows a single hair, this phenomenon may seem like a miraculous demonstration of hair multiplication.

However, a more likely explanation is that what was extracted was one or more of the in a large sized follicular unit. For example, a subset of a follicular unit consisting of four hairs may have been removed and inserted into the recipient area. Therefore, hair was not actually multiplied. And what ends up happening as a diminished and depleted looking density in the final outcome.

It is always important for patients to become acquainted with basic concepts used in FUE hair transplantation, such as follicular unit grafts. This will help with the understanding of a more complete picture regarding actual processes at work within an operation, as opposed to the mere acceptance of surface information.