Acne, also known as brucellosis and acne, is one of the most common diseases in dermatology, with a fairly high incidence, and more than 80% of patients may have suffered from it. It is a chronic skin disease of the follicular sebaceous glands that eventually tends to manifest itself as clogged hair follicles and can develop into inflammatory papules, pustules, nodules, cysts, acne, formation of pigmentation marks, enlarged pores, and even scars and other skin damage. Properly controlling the development of acne can have a significant impact on the final outcome, but the obvious inflammation at the lesion in some patients may make it easier for serious side effects such as scars to form. There are many acne treatment options, such as conventional medications (retinoids, antibiotics, etc.), fruit acids, lasers (IPL, PDL, etc.), physical therapy (needle picking, hormone injections, etc.) and photodynamic therapy. Photodynamic therapy is a relatively new method for patients with moderate to severe acne.
PhotodynamicTherapy (PDT), also known as light irradiation therapy or photochemotherapy, is a new technology that uses photodynamic reactions for disease diagnosis and treatment based on the interaction of light, photosensitizers and oxygen. The physical therapy of acne. Successful treatment with photodynamic therapy requires the following three elements: first, a photosensitizer, i.e., a photodynamic therapy drug; second, molecular oxygen; and third, a light source, i.e., an LED light source device, currently clinically adopted as 633 nm red light or 417 nm blue light. As a therapeutic drug 5-amino-4-ketovaleric acid hydrochloride (5-ALA) itself is not a photosensitizer, after topical application, it is transformed into a strong photosensitive substance protoporphyrin IX (PpIX) in the body, and after illumination with specific wavelengths, a photochemical reaction occurs to achieve therapeutic effects. PDT treatment for acne is a multi-pathway treatment that targets the four major causes of acne, firstly, it can directly kill Propionibacterium acnes; secondly, it can target the sebaceous glands, inhibit sebum activity and reduce sebum secretion; thirdly, red light has anti-inflammatory and restorative effects; another point is that it can act on keratin-forming cells to reduce hair follicle obstruction.
The first relevant study was conducted, namely the 5% ALA red light photodynamic 4-week treatment protocol. The drug concentration is 5%, the light source is 635nm red light, and the equipment is Omena’s equipment. The application method was to apply the configured 5% ALA gel externally to half of the face and seal the package for one hour away from light. The treatment is given once a week for 4 consecutive sessions. The test side was treated with 5% ALA + red light and the control side was treated with red light alone. The efficacy was evaluated at the second week after the end of the treatment. The results of the clinical study showed that the efficacy of photodynamic therapy was significantly better than that of red light alone. The overall rate = cured + effective + effective. The total effective rate of the ALA photodynamic group was 81,49%, while that of the red light alone group was only 51,85%, with a statistically significant difference between the two groups. Another clinical study of domestic physicians used 10% ALA red light PDT to treat moderate to severe acne, sealed packets for 3 hours, once every 2 weeks, with a course of 1 to 3 times designed according to the patient’s condition, and the control group used oral isotretinoin orally, 10 mg twice daily, and the efficacy was evaluated at the 2nd/4th/6th weeks after treatment. The results of the study showed that 10% ALA-red light PDT was significantly more effective than oral isotretinoin in the treatment of acne. The overall effectiveness of the photodynamic group was higher than that of the oral isotretinoin group when evaluated at weeks 2, 4 and 6 after treatment. Therefore, ALA photodynamic therapy can replace oral isotretinoin and can be the treatment of choice for moderate to severe acne.
The operation process of photodynamic therapy for acne can be briefly divided into the following steps: drug preparation, dressing, package sealing and light exposure.
1.Drug preparation: 5% of 5-ALA
2.Light source and wavelength: LED photodynamic therapy instrument red light 633nm±10nm
3.Sealing time: 0,5-2h (1-1,5h recommended)
4.Lighting time: 20min
5, light dose (energy density): 72-126J/cm26, light distance: 10-375px7, the course of treatment and the number of treatment: 3 times a course of treatment8, treatment interval: the recommended treatment interval of 7-14 days, should not exceed 4 weeks Indications.
1. Cases of acne that are not effective with traditional treatment methods or cannot be controlled.
2. Acne cases in which antibiotic treatment is not appropriate.
3, acne cases that cannot tolerate the stimulation of topical medications.
4, more severe cases of acne.
5, acne cases with liver or kidney function impairment.
6.Severe acne cases that are prone to scar formation causing cosmetic problems.
Contraindications.
1, Patients with skin light allergy to the wavelength range around 632, 8nm.
2.Persons with porphyria or known allergy to porphyrins.
3, Patients with known hypersensitivity to any component of topical aminoketovaleric acid hydrochloride solution.
4, pregnant and lactating women.
5, those taking photosensitizing drugs.
6, patients with photosensitive diseases, such as SLE, chronic photosensitive dermatitis, etc.
Some treatment reactions may occur during photodynamic therapy, and these reactions have often occurred in the past with photochemotherapy. For example, there may be slight stinging in the process of phototherapy, erythema and swelling in the treatment area, transient acne aggravation, and pigmentation and dry skin may occur in a very small number of patients, but these treatment reactions do not require special treatment and can be relieved by themselves.