A Comparative Clinical and Histologic Study of Hair Transplantation Using Er:YAG, Er:YAG/CO2, and Standard Punch Techniques

BACKGROUND: This study compares the effects of Er:YAG laser alone, Er:YAG/CO2 laser at 5 W (low power), Er:YAG/CO2 at 10 W (high power), and standard punch techniques in 10 men with androgenetic alopecia. OBJECTIVE: To study the clinical and histologic features of hair transplantation with recipient graft defects created by a new hybrid Er:YAG and CO2 laser. METHODS: Ten male patients (mean age 34 y) with Norwood IV-VI androgenetic alopecia had hair replacement surgery with the recipient sites divided into four quadrants comparing cold stell, erbium, combined erbium low-power CO2, and combined erbium high-power CO2 technologies. Hair growth, intraoperative procedure, lateral thermal damage, and patient satisfaction were compared, utilizing each of the four stated technologies. RESULTS: The addition of CO2 laser at both low and high power settings resulted in improved hemostasis when compared with standard punch or Er:YAG laser alone. The mean hair counts were similar for the Er:YAG laser, Er:YAG/CO2 (5 W) laser, and standard punch at both 3 and 6 months after treatment. Lateral thermal damage was not significantly increased by the addition of low-power CO2 to Er:YAG. The addition of high-power CO2 (10 W) laser resulted in slightly lower mean hair counts at 3 months, but significantly decreased at 6 months (P =.05). Also, high-power CO2 laser caused significantly increased lateral damage. There were no detectable differences in hsp70 expression among the groups. CONCLUSION: The addition of 5 W CO2 laser to Er:YAG laser results in better hemostasis than Er:YAG laser alone, while not significantly diminishing mean hair counts or inducing increased lateral thermal damage.