HPD-PDT SOME TECHNICAL CONSIDERATION

HPD is abbreviation of Hematoporphyrin Derivative
It is a name of a photosensitizer,a chemical compound which will be sensitized and reacted to light.
The pathological cells which retain photosensitizer molecules will be dead due to direct cytotoxic process.
The bloodvessels nurturing the cancer will be shut down.
The necrotic cancer will stimulate the immunity of cancer patient.

The laser:

The machine generates the red visible laser light with a wavelength of 630 nm.The deviation of output wavelength is +/- 5 nm.
The output power of each way (of 3 ways) is from 100 mW to 1000 mw( 1 W),continuously adjustable.
The instability of output power is less or the same of +/- 10 %
The semiconductor laser beam,as the output power is less than 1 Watt,it may lead to three-degree burns on;ly in the situation of focusing or less than 10 mm distance to light extraction end
in using flat-head fiber.

Safety conduct

-Do not look directly at laser beam and its reflex.The visible red light is harmful to eyes.
-All field operator should wear protective glasses
-The protective glasses are specific in its optical density to the laser wavelength which provide enough protection to radiation of 630 nm laser beam
-Patient should wear protective glasses or putting mask on patient's face
-The exposed parts of patient's body should be covered with cloth cover
-Possible explosive matters should be forbidden (alcohol,gasoline,organic solvent.)
-Clothing,gauze and other flammable substances should be removed from the optical path
-A fire extingusher should be placed in the laser area
-Reliable grounding is very important to operation
-Warning labels should be placed to make personsaware of laser operation