The Basics of Laser (4)

What is photochemical effect of laser?

The main concept of photochemistry concerns a certain molecule which functions as a photosensitizer. With the existence of photosensitizer in a particular cell (e.g. cancer cell), the cell becomes sensitive to the damage caused by the photon absorption from a certain wavelength. The effect is selective and does not damage normal cells.

What is selective photothermolysis effect?

It is the thermal lytic effect resulted by light pulse which is selectively absorbed by pigmented target such as melanin and hemoglobin. Recent research showed that this effect enables cancer therapy with combination of selective nanophotothermolysis using primary and secondary antibodies, and gold nanoparticles. Laser radiation will form bubbles on the cancer cells’ wall and cause selective damage to the cancer cells.

What are the safety issues to be concerned in the use of laser?

A laser surgeon has medical, legal, and ethical responsibilities. He/she has to acquire information regarding basic laser knowledge, how to operate laser equipments, the indications, and contraindication of laser (“If you don’t need a laser,don’t use one but if you need it use it properly”). It is important to follow instructions from the manufacturers and laser safety officer at laser-applied institutions. Always use goggles (laser safety eyewear), smoke evacuator, warning sign on operating room entries, and laser safety doorlock.

How should laser be properly used?

Mind the buttons and facilities provided in the laser machine (main switch, safety keyswitch, standby/ready switch, emergency off switch, power regulator, mode regulator, frequency/pulse regulator, time regulator, fluence calculator). Turn on the main switch, then the safety keyswitch. Set the necessary parameter, use adequate protections, change standby to ready, direct the handpiece to the target, step on the footswitch after the direction is set correctly. Keep laser in vertical position against tissue surface and keep the movement so that the speed is constant. Release the step on footswitch after it is done. Repeat necessary procedures. Afterwards, turn off all switches in reverse sequence.