Narrowband UVB phototherapy
What is narrowband UVB phototherapy?
Narrowband UVB is the most common form of phototherapy used to treat skin diseases. It is especially useful in the treatment of psoriasis but can also be used in the treatment of many other skin conditions. For example severe atopic eczema not responding to conventional topical treatment, vitiligo, pruritus without rash, lichen planus, polymorphous light eruption, early cutaneous T-cell lymphoma and dermographism.
“Narrowband” refers to a specific wavelength of ultraviolet B (UV) radiation, 311 to 312 nm. This wavelength is a small component of natural sunlight. It is safer, faster and more effective than “broadband UVB”, a broadband source of light 290 to 320 nm.
Compared with broadband UVB:
- Exposure times are shorter but of higher intensity.
- The course of treatment is shorter.
- It is more likely to clear the skin condition.
- Longer periods of remission occur before it reappears
What are the side effects and risks of narrowband UVB?
Narrow-band UVB can result in burning, just like sunlight and broadband UVB. As the dose is deliberately increased throughout the course to achieve faster and more complete response, it is usual that most patients will experience a mild sunburn at least once during the phototherapy course. Frequent emollients should be applied to burned skin, and if recommended by the therapist, topical steroids. It sometimes provokes polymorphous light eruption.
Long term exposure to ultraviolet radiation ultimately causes skin ageing and skin cancers. Nevertheless, the cumulative scientific information over decades of use and research shows there is no, or negligible increased risk of skin cancer with narrowband UVB phototherapy in humans. In theory, less UV exposure occurs because the patient is only exposed to therapeutic wavelengths. Research also show that it is no more risky than broadband UVB and probably less risky than photochemotherapy (PUVA).
What does narrowband UVB treatment involve?
Patients attend for phototherapy two to five times weekly, for a course usually lasting 6-10 weeks. After completion of the course, and if the condition being treated is cleared, the treatment can be stopped. However, the treatment can be recommenced if the skin condition relapses.
For whole-body treatment, the patient is placed in a specially designed cabinet containing fluorescent light tubes. The patient stands in the centre of the cabinet, undressed except for underwear, and wears protective goggles. Usually the whole body is exposed to the UVB for a short time (seconds to minutes). The dose of UV is tailored to the patient’s condition, skin type, response to treatment and other factors, and carefully monitored by the phototherapy staff under the supervision of dermatologist.
Shorter bulbs can be used for localised UVB treatment, eg of hands and feet or a small body region.
The amount of UV is carefully monitored by the phototherapy staff. A number of protocols exist depending on the individual’s skin type, age, skin condition and other factors.
Both full body, hand and feet narrowband UV phototherapy are currently available at Pymble Dermatology
Waldmann UV 7002 is the new therapy system with higher safety profile, more efficient and ensure maximum patient comfort. This unit is installed at our practice to ensure patients receive the best UV treatment.
What is the result of narrowband UVB?
The skin may remain pale or turn slightly pink after each treatment. Do inform the therapist if you experience any discomfort. Patches generally become thinner after a few treatments. The response of the treatment can be variable but most patients with psoriasis require 15 to 25 treatments to clear.