Here is the abstract of another presentation that I did at the 2009 ISHRS annual meeting.
Super dense packing (92 grafts/cm2), does it benefit the patients?
For past several years, mega-session with dense packing is the main trend in hair transplant surgery. The graft number and density get more and higher every year.
Does it really benefit the patient in general?
To precisely calculate the growth rate of the transplanted hair, we transplanted hair onto eyebrow instead of the scalp. We transplanted 544 grafts in an area of 6 cm2. The density is 92 grafts/ cm2.
Prior to this case, we usually deliver a density of 40 to 50 grafts/ cm2 on eyebrow transplantation.
We compare the result of the growth rate to find out if super dense packing benefits the patients.
Six months after the 92 grafts/ cm2 eyebrow transplant surgery, we counted 455 hairs. The growth rate is 82%.
We have done about 300 eyebrow cases for the past 15 years and the average growth rate is about 96%.
With the super dense packing technique, we have sacrificed 14% of hair.
To grow 455 grafts with 40 to 50 grafts/ cm2 density, we only need to implant 474 grafts. The last 70 grafts (544-474) were wasted.
In order to achieve 92 grafts/ cm2 density, we have to cut the graft much smaller and instead of making 19G coronal slit, we have to make 20G needle coronal slit.
When we transplant hair onto the scalp, we had the same result. http://hairtransplantion.blogspot.com/2009/08/chubby-vs-skinny-graft.html
In the process of preparing the smaller graft, the technician must trim off all the tissue next to the grafts. Bare graft obviously has lower growth rate.
So far no one knows what the best density for best growth rate is, maybe we never will.
I’m sure that depends on age, health, nutrition, etc. everyone has different limitation. Without knowing the body’s limitation, only looking for higher density is not the patient’s best interest.