Patients with vitiligo and psoriasis have been to the hospital several times, and they may have heard of "308" to a greater or lesser extent. From time to time, I will hear from patients who have undergone hospital phototherapy together how good and fast the effect of 308 on the affected area is. I asked the doctor again, and after the doctor's brief description, I found that 308 seemed to be really good. But what exactly is 308? What are the categories of 308? What are their characteristics? It is believed that many patients are not very clear.But that's okay, let's do a big doxxing of 308 today!
1. What is 308 and what are the categories
At present, the "308" used in the dermatology department of the hospital to treat psoriasis and vitiligo refers to ultraviolet light with a peak of 308nm. In fact, there is more than one kind of 308, because there are many kinds of light sources that can emit the 308nm band, such as the rapidly developing 308LED light, as well as the earlier 308 excimer laser and 308 excimer light.
Next, we analyze the characteristics of 308 LED light, 308 excimer laser and 308 excimer light.
2. Analysis of the characteristics of 308LED
(1) 308LED principle
LED (Light Emitting Diode) is a semiconductor electronic component that converts electrical energy into light energy. LEDs made of different materials emit different wavelengths of light, and UVB LEDs made of aluminum gallium nitride (AlGaN), a next-generation semiconductor material, emit ultraviolet light with a peak wavelength of 308nm.
(2) Features of 308LED
As a new type of light source, it has many distinctive advantages, including: (1) 308LED light source is single and pure, and does not contain other wavelength stray light, which means that the light source can treat the affected area and improve the treatment efficiency; (2) The output intensity of 308LED is high, which can meet the clinical demand for high-dose treatment of local skin lesions and accelerate the treatment process; (3) The service life of LED is super long, up to more than ten times that of the previous two generations of light sources, and at the same time, the maintenance cost is low. In the 308 therapeutic field, it is a more economical treatment. (4) The power supply mode is low-voltage DC, and the safety is guaranteed.
(3) The development trend of 308LED
LED technology has developed rapidly in the field of visible light lighting and has been widely recognized by the public, making businesses see the prospect of its application in the deep ultraviolet band for disease treatment. Experts in science and technology and medical circles predict that UV-LED is bound to have a broader future, which is the trend of 308nm phototherapy.
3.Analysis of the characteristics of 308 excimer laser
(1) 308 excimer laser principle
Compared with 308LED, 308 excimer laser may be more familiar to patients. It is emitted by a laser filled with a gas mixture of xenon chloride (XeCl).
(2) Characteristics of 308 excimer laser
It is characterized by a single wavelength and high intensity. However, lasers are more expensive and have higher equipment costs; At the same time, although the laser has a long service life, the gas filled in the laser needs to be filled regularly, and the maintenance cost is high, so for patients, the single treatment price of 308 excimer laser is higher, and the economic burden will be heavier.
(3) The development trend of 308 excimer laser
The laser machine can only be operated by professionals in hospitals, and cannot be used at home.
4. Analysis of 308 excimer light characteristics
(1) 308 excimer light principle
308 excimer light is emitted from a lamp filled with a mixture of XeCl gas. Although there is only one word difference between 308 excimer light and 308 excimer laser, there is still a difference between the two.
(2) Characteristics of 308 excimer laser
Although it is not a single wavelength, the spectrum is narrow and the output intensity is high, which can meet the clinical needs of high-dose treatment of local skin lesions. Its light source is generally characterized by a short service life, and its output intensity will gradually decay with the extension of the use time, and the lamp needs to be replaced regularly, so the equipment maintenance cost is relatively high, and the economic pressure on patients is still greater.
Many patients are unable to go to the hospital for phototherapy on time due to various reasons, so for patients who cannot guarantee regular phototherapy treatment, doctors will generally recommend that they choose the home 308 phototherapy device and carry out home phototherapy under the guidance of the doctor.
So, what are the things to pay attention to when using the home 308 light therapy device?
1. Do not expose to sunlight after exposure
Although phototherapy is used to treat vitiligo through ultraviolet radiation, patients should still be careful not to let the vitiligo bask in the sun after irradiation, otherwise it may cause blistering in the vitiligo area and aggravate the condition of vitiligo.
2. Don't touch the water immediately after the light
If you take a shower and touch the water immediately after irradiation, it will affect the absorption of light by the skin, which will affect the normal effect of phototherapy. It is recommended that vitiligo patients take a bath after 6 hours of phototherapy, or rub the white patches exposed to the light, so as to ensure the continuity of the light effect, maintain the effect of light, and increase the treatment effect of vitiligo.
3. Avoid blindly pursuing large doses
Many friends think that the redder the light, the better, so they increase the dose to find the skin very red. In fact, the longer the light is illuminated, the more red the better. Generally, it is advisable to redness for 48~72 hours after one treatment, and 2~3 times a week is the best.
Blisters, redness, swelling, and pain on the skin after irradiation indicate that the phototherapy dose is too large, at this time, the phototherapy should be stopped immediately, some scald cream can be applied, and after the symptoms improve, the dose should be adjusted to continue phototherapy, and the dose should be reduced
4. Do not interrupt the illumination at will
Vitiligo light exposure should have a certain degree of continuity, and it is important not to stop phototherapy without authorization if it is intermittent or does not see any effect in the near future. Some friends are too anxious during phototherapy, and they stop illuminating after a few times without effect. It usually takes 1-2 courses (20 sessions per session) to assess the efficacy. It takes a while for the proliferation of melanocytes and the production, movement, and aggregation of melanin to form pigment islands, and it is impossible to see immediate results after a few exposures. Therefore, everyone should not be anxious, it is necessary to insist on phototherapy.
Some patients feel that their skin has turned dark after being reddened by irradiation, and they are worried that they will not be able to return to normal skin color and do not want to take irradiation. In fact, the light turns black, which means that there is melanin production in the white patches, which means that the treatment has an effect, and at this time, we must adhere to the treatment in order to achieve the best effect. Darkened skin will slowly recover after stopping the light, so there is no need to worry about this problem.
In short, long-term treatment should be considered for chronic diseases, and short-term curative effects should not be pursued one-sidedly, let alone interrupted at will and given up halfway.
References:
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3.Ibuchi Y, Ozaki S, Inoue Y, Saeki H, Funasaka Y. Excimer Laser Penetrates Deeper into Hair Follicles and Activates More Melanocyte Lineage Cells than Excimer Light. J Nippon Med Sch. 2025;92(1):52-60. doi: 10.1272/jnms.JNMS.2025_92-110. PMID: 40058836.
4.Goldstein NB, Koster MI, Hoaglin LG, Spoelstra NS, Kechris KJ, Robinson SE, Robinson WA, Roop DR, Norris DA, Birlea SA. Narrow Band Ultraviolet B Treatment for Human Vitiligo Is Associated with Proliferation, Migration, and Differentiation of Melanocyte Precursors. J Invest Dermatol. 2015 Aug;135(8):2068-2076. doi: 10.1038/jid.2015.126. Epub 2015 Mar 30. PMID: 25822579; PMCID: PMC4683025.
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