What percentage of patients respond to PRP and Acell injections and what is the optimal concentration of platelets and Acell. I am currently 55 years old.

I think you have summed up the current state of PRP/Acell perfectly. I began using PRP at a roughly 5X concentration in 2010 after visiting Joe Greco, who was the first I know of to report on the benefits of injecting ³activated² PRP using his Harvest system. Prior to my endeavor to use PRP, Joe reported that PRP could increase hair diameter. Although I did not feel his study was scientifically sound, I could rationalize this because I have seen perturbation, which is really a turn on of the inflammatory process, increase hair diameter. Although diameter increase following the natural inflammatory process was rare, it seemed plausible that magnifying the inflammatory process by concentrating platelets could amplify the natural inflammatory process and thus result in greater hair diameter increase.

Joe told me that he was getting a positive response in 75% of his patients. I cannot say what percent we are seeing primarily because I do not see all my patients back within a year¹s time simply because most live out of state.

What I can say is that some report improvement and some do not. Results typically last about one year. No one knows if a repeat injection given annually will continue to promote improved coverage. Some come back annually. Some responders do not.

When Joe told me that he was using an extracellular matrix as a scaffold to improve the release of growth factors, I theorized that we could add Acell to the PRP. I began at low concentrations of 1mg/cc, but have since increased to about 5 mg/cc. I¹m not sure that it adds any benefit. It may. It may not. Based on what I was doing, others began using Acell with PRP. Some use much higher concentrations of Acell today.

In 2012 I began using the Angel system to make PRP primarily because I wanted a 6X concentration of PRP and I wanted a low white cell count. The white cells increase the risk of post surgery swelling. I also wanted a 1x concentration for a topical spray to promote healing and prevent infection due to the high white cell count in the 1x topical spray. Later I told Dr. Cooley about the Angel system and he adopted it.

I have some positive results by photograph and some more interesting positive responses using cross sectional trichometry, which is a measure of the surface area of 4 sq cm of hair. Carlos Puig is currently doing a study evaluating the response of females to PRP and ACell injections. So Šstay tuned for those results.

At your age of 55, a hair transplant is probably ok, but I never encourage anyone who is comfortable with nothing or with medical therapy to do a surgical procedure.

What I can tell you about PRP and Acell is that there is no formula that works in all patients. I tell patients who don¹t respond that there is no need to do a second treatment. When someone does respond, I tell that person it may be worthwhile to do another treatment. I believe that most who spin their own PRP inexpensively probably are making a 1x concentration that most likely has a very limited benefit. The cost of PRP is really due to the equipment you have to buy to spin the PRP.

I think you have hit the nail on the head. What we need is some controlled trials. I would love to see this happen in the next year. In the mean time, stay tuned and wait for more specific protocols.