HAIR TRANSPLANT FORUM

[drcole]

another factor to consider is dense packing. in a single patient case a density of 10 follicular units per sq. cm, 20 follicular units per sq. cm, 30 fu per sq. cm, and 40 follicualr units per sq cm were compared for yield. the 10 fu/sq. cm group had a yeild of 97.5%, the 20 per sq cm yeild was 92%, the 30 fu per sq. cm was 72% and the 40 fu per sq. cm yeild was 78%. this does not mean that the hairs which did not grow are dead it means that they did not grow during this study. they may have been resting or in telogen and this can be expected. it may be that the higher densities had a more representative populatioin of the donor area and the lower densities contain more anagen hairs. of course one cannot make generalizations from a single patient study.

[FITLocks]

Leone,

I too found this to be a very interesting post by Dr. Cole.

I will make a small point about density and coverage as it relates to your question about whether 40/50 FU/cm2 are "a little".

People notice baldness when their hair no longer blocks the transmission of light to the scalp. At this stage of balding the hair is not necessarily totally gone, rather, it has miniaturized and lost diameter. The hair is so thin that the person looks bald.What this says to me is that the number of FUs may not be as important as hair shaft diameter for achieving coverage. Hair diameter is a big deal!

Also remember that 40 1-hair FUs will look different than 40 3-hair FUs.

If the hair shaft diameter is good and the number of hairs per FU is high, 40-50 can provide great scalp coverage.

[FITLocks]

http://www.forhair.com/hairtransplant/viewtopic.php?t=144

Leone,

Check out this other post by Dr. Cole. It may provide you with some answers aswell.

[forhair]

Hey leone,
Give me a call at 1-800-368-4247 and ask for the webmaster...
I will help you online to upload the photos
My guess is that you trying to upload a large size photos...more then the quota.

[FITLocks]

"but i have to say that i am still confused; because if it is true that the normal density is more than 100 FU per sq/cm i still do not understand how you can have a good coverage with just 40/50 FU"

An average person will not have 100+ in there donor area. 115 FU/cm2 is a normal density in the CROWN. This area of the scalp contains a spiral pattern (the whorl or swirl) of hair growth. Hairs have multiple directions in this area, more so than the frontal area or back of the head. This is not advantageous for coverage! I believe that nature or God has made up for this deficit by placing more hair in this area. So, again, 100+ is not a representative number for the head. 80 probably is.

Concerning coverage and density….

Let's say you have 80 tall trees growing in a small area of land behind your house. Your tree density is 80 trees/area of your property. This means if you step outside you may well bump into a tree trunk with every step! For a bird flying overhead, the ground is imperceptible. All the bird sees is branches and leaves and tree top coverage. If someone cuts down ALL the trees, the "bald" ground will be apparent to you and this bird. If someone chops down 40 trees and leave 40 trees growing, you will notice from the ground. What about the bird? Well, if the tree branches still criss-cross and the leaves still provide shade, the bird may find the ground imperceptible as if 80 trees were still standing. So losses and gains in density are not always apparent to the eyes. Such is the case with hair on the head.


FU's are like trees. Some have branches…2,3, or 4 hairs per FU. If the hairs have a curl or wave, the braches can criss-cross and give nice coverage. Density is related to coverage but they are different concepts. Density is a relationship between a quantity of something (FUs) and area. Coverage is more of a quality.

If you pluck a hair out of your donor area, you will lose density. You will not lose coverage. If you pluck another hair within the same cm2 area, again you lose density but not coverage. If you puck ALL of the hairs, density AND coverage is lost. So, somewhere between 1% and 99% of the original density will provide coverage. Realistically, it is about 50%, more or less.

So, if you have good donor hair with a donor density of 80-100 fu/cm2, a density 40-50 fu/cm2 might provide good coverage in the recipient area.

[forhair]

You have many options...you can send it to me at webmaster@forhair.com
or you can send them through this form : http://www.forhair.com/contact_page.htm
If you want i can then upload them to this forum without your face...

[drcole]

there was an interesting study done a few years ago by Manny Merritt. He began plucking hairs from a normal sqaure cm of scalp. that is a scalp with no hair loss. he plucked over 50% of the hairs from the sq. cm and there was no evidence of hair loss. this suggested that we can get a full look with a density of about 40 to 60% of the original density in most individuals.

the density on the sides of the head, above the ears averages 60 follicular units per sq. cm, but it can be as low as 30 or 40 per sq. cm.

hair loss is a miniturization of hair. as the hair miniturizes, it allows more light to penetrate. gradually, you see the illusion of thinning. the miniturization must reach a critical level and then you appear thin.

the quality of hair from hair restoration is much different than the miniturized hair on top of the head. we do not need to match the original density to acheive the illusion of fullness.

it is a very good question regarding percentages of growth based on density. i typically transplant 40 to 50 per sq. cm in one pass. this makes some look very full, but others need more. could it be that we do not see as high a yeild when we pack more densely? this deserves further study. most likely, it is the quality of hair that controls the result. someone with more three hair natural follicular units will look fuller than someone with more one and two hair natural follicualr units. also, someone with a more coarse hair will look fuller than someone with finer hair.

the study that compared different densities was done in only two patients and they were done at different times. the physicians who did the study do not typically pack as densely. they wanted to show that a higher density achieves a lower yeild. if you want to show a particular result it is much easier to do it in one patient. also, the small sample size of a single box with 10 follcular units probably did not achieve a fair sample of the donor area. this box may have had fewer hairs in telogen or hairs in catagen. thus, more hairs would have grown immediately. a box with 40 follicualr units will give a better overall representation of the donor area. it is perfectly acceptable to acheive a growth yeild of 82% since a large percentage of hairs may be in telogen or catagen at any given time.

[forhair]

He Leon,
I recived your photo...i will let Dr, Cole look at them.
do you also want me to upload them to the forum?

[Patrick]

Very interesting!!!
Fit ,I liked the criss cross effect of leaves...
As we noticed ,dense packing is not synonyme of full coverage effect.There is many other factors as hair caliber,criss cross effect,...
A little observation:it is very difficult (or let say I don't see the reason ) to conduct a study about yield in function of density.
First of all you have to compare the same things.The Fu needs to have the same #of hairs.Then you can say with a 2 hairs fu ,we transplant 10,20,40,50 in the same area(without forgetting that area should be representative of the entire scalp) and then compare the percentage of yield.
Another issue.If I have single hairs,I can place close together 70 to 80 grafts in a square cm.In the same patient if I have fu with 4 to 5 hairs,it's physically impossible to put 70 to 80 units close together.Some physicians ,in order to dense pack,have to fractionate the unit;and we all know that those fractionated grafts are more fragile and less viable than the natural unit.
Last thought:if Ihave a cup and I fill it with beach sand ,I may need a million.If I filled the same cup with stones,I may need a hundred.Which cup is fuller than the other?No one ;they are both full.It's about occupation...(Ah,Ah,Ah...).

[forhair]

This are leone photos as he requested.
I'm inviting the forum members share their thoughts on his photos.

[FITLocks]

Check these shock loss posts out: http://www.forhair.com/hairtransplant/viewtopic.php?t=190

What is your age again Leone?

[FITLocks]

Leone,

Nice to hear that your hair loss has been somewhat slow and stable over the years. This could work in your favor. Your situation would be a bit more delicate if you were 21 instead of 31.

Medication (if appropriate in your case) can work well in coaxing your existing hair to remain in the thinning areas.

“As you can see i have problems in the front of my head,is it my case a good one for FIT/FUE method?”

Most good candidates for HT are good candidates for FIT.