A comparative clinical and histologic study of hair transplantation using Er : YAG,, Er : YAG/C0(2), and standard punch techniques

Background. This study compares the effects of Er:YAG laser alone, Er:YAG/C O2 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 transplant ation with recipient graft defects created by a new hybrid Er:YAG and CO2 l aser. Methods. Ten male patients (mean age 34 y) with Norwood IV-Vl 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, intraoperat ive procedure, lateral thermal damage, and patient satisfaction were compar ed, utilizing each of the four stated technologies. Results. The addition of CO2 laser at both low and high power settings resu lted in improved hemostasis when compared with standard punch or Er:YAG las er alone. The mean hair counts were similar for the Er:YAG laser, Er:YAG/CO 2 (5 W) laser, and standard punch at both 3 and 6 months after treatment. L ateral thermal damage was not significantly increased by the addition of lo w-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 decrease d at 6 months (P=.05). Also, high-power CO2 laser caused significantly incr eased lateral damage. There were no detectable differences in hsp70 express ion 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 me an hair, counts or inducing increased lateral thermal damage.