Comparison of the Efficacy Between Regional Nerve Block and Ring Block as Local Anesthetic Techniques for Platelet-Rich Plasma Treatment.

Introduction Platelet-rich plasma (PRP), a solution of concentrated platelets, has been widely used to promote wound repair and tissue regeneration. In the treatment of pattern hair loss, platelets in PRP secrete an abundance of growth factors, including platelet-derived growth factor (PDGF), fibroblast growth factor(FGF), and many more, which stimulate and increase signaling molecules and accelerate cell proliferation. In the PRP treatment for hair regrowth, the supratrochlear nerve (STN) block and supraorbital nerve (SON) block are given to anesthetize the scalp up to the vertex except for the temporal region. The ring block is the common local anesthetic technique used by infiltrating local anesthetic agents around the target area. The primary objectives were to compare the pain and anesthetic success rates produced by regional nerve blocks and ring blocks. Materials and methods A sample size of 100 patients undergoing PRP treatment for hair regrowth were taken as the subjects for the study. Patients were allotted into two groups by randomization. Group 1 was given regional nerve blocks as the anesthetic technique used for local anesthesia, and group 2 was given ring blocks. In the study group, STN and SON blocks as the regional nerve blocks were given 2% lignocaine with 1:80000 adrenaline to anesthetize the area, and the PRP was injected from the anterior hairline up to the vertex of the scalp, not involving the occipital and temporal regions. In the control group, a ring block was given for the same procedure. Participants from both groups were assessed for the pain and analgesia caused by ring block and regional nerve blocks using the visual analog scale (VAS). Results A mean rank of 30.28 was observed for the regional nerve block technique, and a mean rank of 70.72 was observed for the ring block technique. A p-value of 0.00 that is <0.05 was observed, which shows there is a significant difference in the pain and the analgesia experienced by the subjects between the two groups, during and three hours after the procedure. Conclusion PRP is one of the most commonly used treatments for hair regrowth. The ring block is the common local anesthetic technique used for producing anesthesia, while regional nerve blocks are more effective in producing local anesthesia. This study proves that STN and SON blocks are better anesthetic techniques than the ring block technique for PRP treatment in hair growth.