How do doctors know how many graphs the get out of the donor area?

[THINinHOUSTON]

If you want say a 4500 graph procedure..How does the Dr. know how big of a strip to take out?

 

Do they guess the density per sq.cm. do some math and remove a strip with a width and length that adds up?

[THINinHOUSTON]

If you want say a 4500 graph procedure..How does the Dr. know how big of a strip to take out?

 

Do they guess the density per sq.cm. do some math and remove a strip with a width and length that adds up?

[notgoing2gobald]

To the best of my knowledge PRIOR to strip excision they just "eye-ball" it, of course aided by *much* experience; then once the strip is removed they can tell you what your donor density was in terms of grafts per square cm. Im left w/the impression---from H&W at least---that they typically slightly "under-estimate" what they think they are going to be able to get from you, so there is no dissapointment when all is said and done...But, I think their fairly accurate as to the read of your donor.

[Bill - Seemiller]

ThininHouston,

 

There are tools that can give physicians an accurate hair density reading, but I know that many physicians eyeball density based on their experience (as notgoing2gobald said).

 

Then they will estimate the appropriate length and width of the donor strip needed to obtain the approximate number of grafts needed, considering the patient's donor laxity and donor "safe zone".

 

If you take the average donor hair density (approximately 80 FU/sq cm) and multiply it by the width and length of the strip, you have the approximate number of grafts. A strip of 30cm long and 2 inches wide with average donor hair density will yield approximately 4800 donor hair grafts.

 

Bill

[TheHairLossCure]

I don't think that most doctors, at least the ones talked about on this site, are eyeballing donor density prior to donor tissue removal. You need to make donor-density measurements so that the strip yields (approximately) the number of units discussed during the consult/planning process.

[Bill - Seemiller]

don't think that most doctors, at least the ones talked about on this site, are eyeballing donor density prior to donor tissue removal. You need to make donor-density measurements so that the strip yields (approximately) the number of units discussed during the consult/planning process.

 

TheHairLossCure,

 

Can you define this further? I know there are tools that can be used to measure density, but in all 3 hair transplants I've had, I do not recall anyone measuring my donor hair density by any scientific method.

 

Bill

[MORE_HAIR]

Bill,

 

Pretty interesting on how the #'s add up in relation to strip size/length/donor density.

 

My strip size was just about 30cm/12 inches.

My donor density was a bit below Avg.so your numbers add up if my strip width was around an inch.

 

What struck me though was you mean to tell me if the patient that gets the 4500 graphs with avg. density the strip is 2 inches wide...wow !!!

That seems pretty wide when you look at a ruler.

 

Great info...don't read alot about this.

 

Thanks,

 

MH

[Dr. Timothy Carman]

As pointed out by Bill, the amount of donor is related to 1)The length of the donor strip (cm); 2)The density of the hair (Follicles/cm2); and Scalp Laxity (cm) (which ultimately determines the width of the donor in cm). The way Bill calculated in his example addressed these points, but you must remember to keep all measurements in the same units (cm). For the example Bill gave, the yield would actually be 12,000 follicular units (The width of two inches = approx 5 cm). (5cm X 30cm X 80 FU/cm2) (BTW, I'm sure Bill meant 2 cm, not 2 inches)

In assessing the donor, there is an "eyeball" estimation made with respect to the donor density. In general, "normal" density of the donor area is about 100 follicular units/cm2. While there are more formal ways to measure hair density, this step is usually done as an "eyeball estimate" based largely on the surgeons previous experiences, and, at least in our practice, that estimate tends to be very accurate indeed. The donor length available is pretty straight forward; one needs to assess how far forward on the lateral portions of the patient's head the incision can be brought to, and this depends on the density of the hair and whether or not (in the surgeon's opinion) that density is great enough to cover the resulting scar in that area. Those endpoints form the line "A" to "B", which is then measured. Finally, a judgment as to how wide the donor can safely be is made based on the surgeons impression of the laxity the scalp on the sides and back of the head.

And yes, this estimate is usually made as part of the initial consult interview.

 

Timothy Carman, MD

[Jotronic]

I think Bill meant to say 2 cm, not 2 "inches". I hope he meant to say that anyway

 

The problem with measuring donor density is that density in the donor area is rarely if ever consistent from one side to the other. Where one area, say the back, has 90 to 100 fu per cm2 the laterals may be 75 fu per cm2. Eyeballing it is not that hard if you have the experience and in fact becomes second nature after enough time.

[MORE_HAIR]

After thinking about it i really thought 2 inches was a bit much...lol.

 

Even in my case the strip width was far less than an inch.

 

And yes...all the docs I met with "eyeballed it" and all explained how the density differs from back to the laterals.

 

MH

[Bill - Seemiller]

I think Bill meant to say 2 cm, not 2 "inches". I hope he meant to say that anyway

 

Whoops! Good catch Joe. Yes, I meant 2 cm Shew...2 inches would be a WIDE strip!

 

Bill

[whymewhy]

If the strip is 30 cms wide that means it can go up on the sides right? unless you have a pretty big/weird shaped head

 

Bill, your scar goes pretty high up on the sides. This is the 1st time I have actually seen a scar pic, so maybe I am over reacting. But, is that safe? Doesn't that look weird? can you hide it?

[Bill - Seemiller]

whyme,

 

That's correct. A typical strip length is ear to ear in length...some go longer depending on the patient's need for more grafts and personal "safe zone".

 

Bill

[TheHairLossCure]

Can you define this further? I know there are tools that can be used to measure density, but in all 3 hair transplants I've had, I do not recall anyone measuring my donor hair density by any scientific method.

 

I find that odd, but perhaps it is the case. You got some nice hair though I am sure you have seen those charts from Shapiro's office (posted by Janna) were the doc writes in the patient's donor density. Also you may have read accounts from some of Dr. Rose's patients were they refer to specific donor densities. You can cut/clip very small portions of hair (in consults or pre-surgery) and use magnification (like a densitometer) to count hair and follicular units per unit area. If you do it in multiple areas over the donor zone you will get a good picture of the patient's average hair and donor density. From there you can calculate the dimensions of the strip.

 

Now, on the other hand, if you wanted as many grafts as possible in a session, measuring density is not that important. If you pull more tissue you will get more grafts and that is the goal. Just remember, some guys are not going in for as many as possible.