Platelet rich plasma (PRP), also termed autologous platelet gel, plasma rich in growth factors (PRGF), platelet concentrate (PC), is essentially an increased concentration of autologous platelets suspended in a small amount of plasma after centrifugation. Basically, patient’s blood is collected and centrifuged at varying speeds until it separates into 3 layers: platelet poor plasma (PPP), PRP, and red blood cells. Usually 2 spins are used. The first spin (“Hard spin”) separates the platelet poor plasma (PPP) from the red fraction and platelet rich plasma (PRP). The second spin (“Soft spin”) separates the red fraction from the PRP. The material with the highest specific gravity (PRP) will be deposited at the bottom of the tube. The whole process takes approximately 12 minutes and produces a platelet concentration of 3–5x that of native plasma.
Platelets play a fundamental role in hemostasis and are a natural source of growth factors. Growth factors, stored within platelet α-granules, include platelet derived growth factor (PDGF), insulin like growth factor (IGF), vascular endothelial growth factor (VEGF), platelet derived angiogenic factor (PDAF), and transforming growth factor beta (TGF-β). The release of these growth factors is triggered by the activation of platelets that can be initiated by a variety of substances or stimuli such as thrombin, calcium chloride, or collagen. Growth factors are involved in key stages of wound healing and regenerative processes including chemotaxis, proliferation, differentiation, and angiogenesis. According to the definition of PRP, it may be assumed that these growth factors are present at increased concentrations in PRP. In addition to growth factors (GFs), platelets release numerous other substances (e.g., fibronectin, vitronectin, sphingosine 1-phosphate, etc…) that are important in wound healing. An advantage of PRP over the use of single recombinant human growth factor delivery is the release of multiple growth factors and differentiation factors upon platelet activation. Recently, the morphologic and molecular configuration of PRP was reported, it showed PRP is a fibrin framework over platelets that has the potential to support regenerative matrix.
The rationale for using PRP in soft and hard augmentation are to accelerate vascularization of the graft, improve soft tissue healing, reduce post operative morbidity, and enhance bone regeneration. Advantages of using an autologous PRP include no risk of cross reactivity, immune reaction or disease transmission. In addition, the use of PRP improves handling of particulate graft materials and easier packing into a grafting site, thus facilitating space maintenance and potential bone regeneration.
Since PRP contains several GFs (e.g., PDGF, VEGF, etc…) that are capable to stimulate angiogenesis and increase fibroblast cell differentiation, using PRP to promote healing of all types of musculoskeletal injuries and soft tissue healing including hair loss, has been proposed and used successfully by many practitioners in the regenerative medicine field.
PRP for HAIR LOSS
PRP injection is a simple, cost effective and feasible treatment option for androgenic alopecia, with high overall patient satisfaction.
Hair loss has a significant influence on psychological distress and is associated with low self-esteem and depression. Treatment options for androgenic alopecia are very limited and include topical minoxidil and oral finasteride (FDA approved) either alone or in combination.[6,7] However, there are several reported side effects such as headache and increase in other body hairs for minoxidil[6] whereas loss of libido has been reported with oral finasteride. Finasteride also interferes with genital development in a male fetus and is contraindicated in pregnant women and those likely to become pregnant.[7,8]
PRP has already attracted attention in plastic surgery, orthopaedic surgery and cardiac surgery because of its potential use in skin rejuvenating effects, rapid healing, reduced infection, decreased chance of hypertrophic keloids and scars.[9,10] Growth factors are known to activate the proliferative phase and transdifferentiation of hair and stem cells and produce new follicular units. bFGF is reported to promote the in vitro proliferation of papilla cells, and thereby plays a key role in elongating hair shaft.[11]
We prepared PRP by double spin method, in which blood cell layers were manually separated. Activation of platelets through coagulation triggers the secretion of various growth factors, which produce mitogenic effects in various cell types. Activated PRP promotes the proliferation of dermal papillary cells and prevents their apoptosis.
In our study, the hair pull test became negative after four sessions of PRP. This finding is comparable with the study conducted by Besti et al.[12] This study also observed significant improvement in hair volume and coverage in global pictures, but according to our study, only moderate improvement in hair volume and coverage was observed.[12]
Uebel et al. observed a significant improvement in hair density and stimulation of growth when follicular units were pre-treated with platelet plasma growth factors before their implantation. There was a significant difference in the yield of follicular units on comparing the experimental with the control areas of the scalp. The areas treated with platelet plasma growth factors demonstrated a yield of 18.7 follicular units per cm2 whereas the control areas yielded 16.4 follicular units per cm2, an increase in follicular density of 15.1 percent.[4]
Pre Treatment Photograph
Post Treatment Photograph
