Deep Cooling Characteristics of Multi-Pulsed Cryogen Spray: A New Technology to Assist Laser Lipolysis

•Multi-pulsed cryogen spray (MCS) was proposed to assist laser lipolysis.•MCS can improve deep cooling efficiency and reduce the usage of cryogen.•The optimal duty cycle of 0.039 obtained good cooling effect without frostbite.•Spatial heat transfer has a large inhomogeneity with short pulse duration.•Optimal parameters were recommended to get ideal cooling effect without frostbite.