Hair Transplant Surgery
Step by Step - DA vs. RA

DA = Donor Area
RA = Recipient Area

The first step in evaluating a patient is to analyze the DA x RA ratio, that is, the quantity of hair that the patient has to donate compared to the quantity of hair needed to resolve his or her individual case of hair loss. However, as hair loss evolves, the RA increases and the DA decreases, only stabilizing once hair loss ceases to advance. This is why we must take into consideration that hair loss is progressive when doing this analysis. A serious mistake, made far too often, is to analyze patients as they are in a particular moment, not accounting for the evolution of their hair loss.

For example:

Upon evaluating a young patient (between 20-30 years old) we must remember that hair loss has a tendency of worsening. That is, the RA will increase in size and simultaneously the DA will get smaller as the crown becomes lower.

Therefore any ratio that is determined using a “static” reference as the current situation of the patient will be wrong and destined for failure.

How then do we do a correct evaluation of the DA:RA ratio? First, we take into consideration the family background of hair loss (both the patient’s maternal and paternal sides, up to two generations back).

After, we perform a detailed microscopic evaluation of the DA as well as RA.

All of these considerations, adding the patient’s age, the type of balding and the surgeon’s experience will give us an idea about how the hair loss will progress. Then we are able to indicate with precision the best strategy for your specific case, not only TODAY, but for the REST OF YOUR LIFE.

In older patients (more than 50 years old) or in young patients with advanced, established cases of balding, this evaluation is not so necessary, because as hair loss has practically stabilized, we have a more precise notion of the DA x RA.

Even still, this balance could trick us if we did not have experience.

For example, see the two cases below that appear to be similar, however are not, as the case on the left the DA x RA balance is more positive as the donor area is greater and the bald area smaller.

Obviously the case on the left will have a better result in terms of volume and density than that of the case on the right.

But can the patient on the right have hair transplant surgery? Will it turn out well?

Of course, and to understand how, we suggest you read the topic The Art of Hair Transplant Surgery.