logo   Dr. Bertram Medical Hair Transplant
眉 髮 醫 學 移 植 中 心 ( 香 港 )

( 852 )  3421-1138

 
How Many Grafts Do You Need ?


... We Do Not Guess, We Measure.


Our latest technique of Follicular Unit Transplant uses exclusively Follicular Unit (FU). The total number of graft required for a good result is governed by 2 factors:

  • The AREA of bald area to be transplanted;
  • The DENSITY or the number of graft desired per sq.cm;
Number of Graft   =   Area (sq.cm)    X   Density (FU per sq.cm )



Area to be Transplanted

  Where To Transplant
During the consultation the patient and doctor need to first agree on where to transplant. Obviously the patient may want to fill up every empty spots. However the following factors must be considered :
  • Extent of current hair loss;
  • Potential and extent of future loss;
  • Is patient taking medication to prevent further loss;
  • Level of the re-designed hairline;
  • Quality of donor hair;
  • Amount of available donor hair for the life-time;
  • Budget of the patient.
Priorities
Please be reminded that the purpose of hair transplant is not just to replace lost hair, but to create a visual illusion of not being bald. The most important part is to restore a hairline. Therefore hairline restoration should be the first priority. This is usually the objective of the first transplant session. The empty crown may be left for the subsequent procedure.

If even less donor hair is available, our doctor may suggest to distribute the grafts unevenly, being more on the parted side. His experience and artistic mind will help to achieve your best possible result with the least number of grafts. For example the creation of a widow peak with just 10-20 grafts may make the hairline looks 'lower'.

How We Measure the Area

Marking the to-be-transplanted area   Tracing the area on a plastic sheet

There are many methods to measure the transplanted area. For accuracy we are using the method described by Dr. Chang, which is simple and easy to apply. We first outline the to-be-transplanted areas with an erasable marker, then lay a clear plastic sheet on top of the marked area and trace the outline of the bald area with a fine marker.

Counting the number of squares   The area on plastic sheet

We then transfer the marked wrap onto a metric scale containing boxes of 1 cm2 and count count the actual number of blocks. The result is the area expressed as number of square centimeter.


The Density Issue

  How Much Is Enough?
Just to refresh your memory, the normal density( hair and follicular unit ) are as follows :

  Caucasian Africans Asians
Hair Density 200 / sq.cm 160 / sq.cm 170 / sq.cm
FU Density 100 / sq.cm 60 / sq.cm 90 / sq.cm

The 50 : 30 Rules
The human eyes are not very reliable sensors, especially in counting hair. The eyes cannot tell the differences when the density is above 50%. Consequently 50%, 60%, 70%, 80%, 90%, and 100% of the original density just look the same from a fair distance.
Density of hair and fullness
Appearance of Fullness
The full-head-of-hair look is maintained until approximately 50% of the original hair volume is lost.

  Early Thinning
When the scalp become visible under bright lights or with wet hair. This implies that about 50% of hair have already been lost in a certain area.

Moderate Thinning
When the scalp becomes see through; and the scalp visible in almost all situations. This occurs when the density drops below 30%.

Bald
When density falls below 10%.

Application in Hair Transplant - the Illusion of Density
The same principle can be applied when replacing hair. We only need to replace 50% of the original density to achieve an appearance of fullness.
Spreading the grafts over a large area, with density below 30%, may look too thin for any satisfactory result.

Recommended Density for Hair Transplant
We use FU density to estimating the number of grafts.

  Caucasian Africans Asians
Minimal Density 40 /sq.cm 24 /sq.cm 35 /sq.cm
Moderate Result 45 /sq.cm 30 /sq.cm 40 /sq.cm
Dense Packing 50 /sq.cm 35 /sq.cm 45 /sq.cm

Other Factors to Consider
The appearance of fullness is not just determined by hair density. The following factors must be considered when planning the number of grafts :
  • Diameter of hair shaft;
  • Color contrast between hair and scalp
  • Straight hair, wavy hair, or curly hair
  • Existing hair


Examples
  Example 1 :
An Asian wants to transplant an area of 50 sq.cm at minimal density, the number of grafts required
      = 50 X 35 = 1,750 FU

Example 2 :
A Caucasian wants to transplant an area of 50 sq.cm with dense packing, the number of grafts required
      = 50 X 50 = 2,500 FU


Tips and Reminders
  • Obviously a larger area with higher density would equal more grafts;
  • There is a critical density below which no visual impact will be perceived;
  • For those with a limited budget or donor hair, compromise should be made on area, but not density. Raise the hairline by 1 cm may save hundred of grafts.

    image
Hong Kong Most Qualified   Hong Kong Most Qualified

CONTACT FORM
Your name : (required)


Gender : Male     Female
You are calling from:
Your email : (required)
Confirm your e-mail: (required)
Phone (Optional) :
Comments / Questions:


 
CONTACT INFORMATION



image
image