Laser surgical device and surgical method thereof

A laser device having a cooling system, the device comprising:

• a laser module configured to irradiates a laser to a target including a blood vessel;
• a sensor configured to detect a temperature of a surface corresponding to the target;
• a cooling module comprising:
• an inlet configured to receive a refrigerant;
• a nozzle configured to spray the refrigerant;
• a conduit configured to provide at least part of a flow path from the inlet to the nozzle for the refrigerant;
• a valve configured to control a flow of the refrigerant in the flow path;
• a refrigerant condition controller arranged between the inlet and the nozzle and configured to provide a heat to the refrigerant before the refrigerant is sprayed by the nozzle;
• and
• a controller configured to:
• control the valve of the cooling module to spray a refrigerant to the surface,
• control the refrigerant condition controller to provide a heat to the refrigerant before being sprayed based on a desired temperature and the detected temperature by the sensor, and
• control the laser module to irradiate the laser while the cooling module is controlled to spray the refrigerant,
• wherein the laser module is controlled to irradiate the laser from a first time point to a second time point, and
• wherein, before the first time point, the desired temperature is set to be out of a critical temperature range that corresponds to a temperature range causing vasoconstriction.