Blind Graft Production: Value at What Cost? (1998)
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Robert M. Bernstein, M.D., New York, New York

Hair Transplant Forum International 1998; 8(6): 28-29.

I was fortunate to catch an early glimpse of the provocative article “Blind Graft Production with Cutting Grates and Multi-bladed Knives” on its way to Dr. Shiell and the Forum. The gauntlet having been tossed, let me be the first to enter the fray. The question at hand is relatively straight forward. When compared to the highly controlled stereo-microscopic dissection of donor tissue harvested as a single strip, do the potential benefits of blind graft production (which use a multi-bladed knife and a cutting grate) more than outweigh their disadvantages and possible risks?

In order to make sense out of the long list of categories used to evaluate the two techniques, I have taken the liberty to organized them into the following groups:

  1. Intrinsic Factors – Factors affecting the surgical outcome that are intrinsic to the techniques discussed and cannot be eliminated.
  2. Extrinsic Factors – Factors that may affect the hair restoration surgery, but ones that can be reasonably modified so as not to significantly impact the outcome.
  3. Economic Factors – Strictly economic issues that have no effect on quality.

1. Intrinsic Factors
Damage to the follicle
Disruption of the follicular unit
Viable hair(s) obtained per graft
Amount of non-hair bearing tissue transplanted
Total recipient wounding
Foreign body reaction
Pseudo-cyst formation
Quality control
Patient variability
Preserving donor supply

2. Extrinsic Factors
Time grafts are out-of-body
Risk of desiccation
Staff training
Staff stress and fatigue

3. Economic Factors
Cost of equipment
Cost of labor
Cost to doctor
Cost to patient

What The Patient Should Do

If I were advising a patient that had to choose between the two hair transplant procedures I would suggest the following:

FIRST: To each of the factors assign a GOOD rating where the technique can clearly or potentially be of benefit, a BAD rating if it may do harm, and disregard those issues that make no difference. (For simplicity, I have assigned each factor a value of 1, although some factors are clearly more important than others.) Then count them all, subtracting the bad from the good.

SECOND: Pick a top-notch surgical hair restoration team that could control the extrinsic factors so that they would have little or no impact upon the surgery.

THIRD: Make a decision taking into account that:

  • This surgery is being performed on your own body.
  • You only have a limited donor supply of hair.
  • You will have to live with the results of the hair transplant procedure (good or bad), for the rest of your life.
  Microscopic Dissection Blind Graft Production
Medical Issues    
Damage to the Follicle GOOD BAD
Disruption of the Follicular Unit GOOD BAD
Viable Hair Obtained Per Graft GOOD BAD
Non-hair Bearing Tissue Used GOOD BAD
Total Recipient Wounding GOOD BAD
Foreign Body Reaction GOOD BAD
Pseudo-cyst Formation GOOD BAD
Ability to Control Quality GOOD BAD
Impact of Patient Variability GOOD BAD
Preserving Donor Supply GOOD BAD
Economic Factors    
Cost to Patient BAD GOOD
TOTAL (good – bad) 9 -9

The Issues
I have eliminated the first three economic factors; Cost of equipment, Cost of labor, and Cost to doctor, since the only factor that really matters to the patient is his cost. All the other economic issues are reflected in this one and are not the patient’s problem.

Extrinsic factors, if not controlled, can play a major role in the outcome of the surgery. Finding a surgical hair restoration team that is properly trained and experienced can minimize these issues. For example, the time that grafts are out of the body can be reduced by utilizing a sufficiently large staff or by taking a donor strip out in sections. Adverse effects can be further minimized or eliminated by proper graft refrigeration. Any risk of desiccation can be easily eliminated by the use of holding solutions and the proper handling of grafts just prior to insertion. In addition, automation may soon make both of these issues moot. A sufficiently large staff that is adequately rotated and working in a comfortable environment will greatly reduce stress. If the patient is diligent in his research, he can pick a surgical team that satisfies these requirements.

The intrinsic factors are the real issue. A 35% incidence in follicular transection that was observed without even using a microscope is, in my opinion, an extraordinary price to pay for a cheaper, faster procedure. It is argued that follicular transection is overestimated when two fragments representing the same follicle are both counted, (this error was not made in these counts) but even if the transection was half that, it would be too much. From my personal experience with a multi-bladed knife with a inter-blade spacing of 3mm, the transection rate was about 20%, and occasionally as high as 35%, so it doesn’t surprise me that transection with blades set at 1mm would easily cause damage in the range of 35% (or even more). In fact, Dr. Rassman, in his own practice, had abandoned using the multi-bladed knife after he had observed the transection rate to be unacceptably high. The fixed blade spacing of the cutting grate used in the next step, would further compound this damage.

Much has been made of Dr. Kim’s studies showing that, under controlled conditions, a portion of transected follicles will grow. What is not often mentioned by those quoting his data, is that the hair that is produced is often finer and more delicate than the undamaged, full thickness terminal hair of intact follicles. Unfortunately for the patient, hair shaft diameter is as important to the final cosmetic outcome of the hair transplant as the absolute number of transplanted hairs.

Another important issue is the fact that multiple blades break up the naturally occurring follicular units. One doesn’t have to do a controlled experiment to understand that a single pass of the multi-bladed knife with blades set 1mm apart will literally decimate follicular units randomly spaced at a density of 1unit/mm2. Again, the fixed spacing of the cutting crate would further divide any follicular units that hadn’t already been broken up with the multi-bladed knife.

Transplanting the whole follicular unit will insure that the greatest cosmetic benefit is obtained from each session. The compact nature of intact follicular units allows them to be placed into very small sites, minimizing recipient wounding. This, in turn, maximizes the amount of hair that can be placed into the cosmetically important areas, while maintaining a totally natural look. Minimal wounding will cause less compromise to the blood supply and produce less scarring. It will enable larger procedures to be performed at one time, and will help preserve the integrity of the recipient bed for future procedures. How much the wounding may be decreased will depend upon the surgical team, but since carefully dissected follicular units contain only about half the volume of the original donor tissue, the total wounding can potentially be cut in half.

The fact that transected follicles may grow under experimental conditions should be of little consolation to the patient who wants to get the maximum benefit from his or her hair transplant procedure. Some hair restoration doctors seem to be flippant about generating hair fragments and consider only whether they will or will not grow. In fact, hair fragments are composed of keratin which can be quite inflammatory and the reaction they incite in the dermis can destroy adjacent follicles. Small hair fragments that do grow may not find their way to the skin surface and can result in pseudo-cyst formation, a locally destructive process. We have all seen this in our practices, and from my experience the incidence is significantly reduced when follicular units are transplanted intact. Bilateral controlled studies would, of course, be helpful to document this for the skeptics.

The ability to control quality is another important issue. It has been argued that quality control is difficult in follicular unit transplantation. That may be true, but to ignore quality all together is certainly not the solution. A team experienced in follicular dissection can consistently generate the highest quality grafts if one puts forth the effort for proper training and continued monitoring. The problem with both multi-bladed knives and cutting grates is that the slightest deviation in alignment can increase the transection significantly and, unlike microscopic dissection which deals with one follicle at a time, there is no way to make fine adjustments along the way.

A final issue is the intrinsic variability of the human scalp from patient to patient, and from one region of the scalp to another. The dissecting microscope is an exquisite instrument for adjusting to this variability. The fixed relationship of the cutting surfaces of the multi-bladed knife and the microtome cannot. Will the doctor performing blind dissection be able to adequately account for this variability in the average patient and will he risk operating on an unwary patient in whom these differences might be profound?

In Perspective
For those of us who embraced follicular unit transplantation at the outset, it could be argued that we might have acted too hasty… before all the evidence was in. But our rationale was that the procedure would improve the quality of our hair transplant. Our critic’s main objection was that it might not be worth the extra effort. If we had been wrong, there was little to lose except time, effort, and unnecessary expense. In this case, when one risks damaging the patient’s donor supply, the patients have much to lose.

The sudden disregard for follicular anatomy exhibited by this “blind grafting technique” runs contrary to much of the progress that has been made in hair restoration surgery over the past 10 years. Hopefully, well-controlled studies will precede the general use of these instruments, so that the extent of damage can be accurately measured.

The “blind grafters” should clearly explain all the pros and cons of this type of dissection to their patients, as well as the limited knowledge we have of this technique so far, in order that their patients have true “informed” consent. Let’s not go back to the days of the old plugs when doctors rarely told their patients all of the short and long-term consequences of their procedures.

Blind graft dissection may indeed have some economic value, but what is the real cost to our patients?

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