Vitiligo is a common acquired hypopigmentary skin disease with an incidence rate of about 0.5% - 2%. It can occur at any age, but is slightly more common in young adults, with equal incidence in males and females. The exact cause of vitiligo is unknown, but it is generally believed to be related to genetic, autoimmune, and neurochemical factors.
What is Wood's Lamp?
Wood's lamp is a commonly used tool in dermatology that emits ultraviolet light with a wavelength of about 365 nm. Under Wood's lamp illumination, depigmented areas of vitiligo exhibit a bright white fluorescence due to the absence of melanin, which allows for easier reflection and transmission of ultraviolet light. Wood's lamp is easy to operate, provides quick results, and is a non-invasive diagnostic method. It is widely used in the diagnosis and treatment of vitiligo and other skin diseases.
How Does Wood's Lamp Help Detect Vitiligo?
When examining a patient with vitiligo using a Wood's lamp, the skin should be in a dark environment. The distance between the Wood's lamp and the skin should be about 5 - 10 centimeters. The doctor will observe the skin lesions under the light. If the lesion exhibits a bright white fluorescence, it is highly likely to be vitiligo. Wood's lamp can detect subtle changes in skin pigmentation that are not easily visible to the naked eye. This helps in the early diagnosis of vitiligo, especially in cases where the lesions are not obvious. It can also be used to monitor the progression of the disease and evaluate the effectiveness of treatment.
What's the difference between IBOOLO Woods Lamp?
IBOOLO currently offers two Wood's lamps, the DE-215 and the DE-315. The DE-215 is composed of 15 white LED lights and 5 UV lights at 365nm, providing two distinct lighting modes: a white light mode and a UV mode. The DE-315, on the other hand, consists of 10 UV lights at 365nm and 10 UV lights at 405nm, offering two different UV modes. The white light is primarily used to examine the surface texture of the skin. The 365nm UV light is mainly utilized to observe fungal skin lesions as well as pigment loss conditions similar to vitiligo. The 405nm UV light is predominantly employed for ALA fluorescence imaging of BCC and AK.
What are the Dermatoscopic Features of Vitiligo?
Vitiligo appears as white, structureless areas under dermatoscopy, representing hypopigmentation with a typical glowing appearance. Other features include perilesional and perifollicular hyperpigmentation, pigmentation networks, and leucotrichia. These features help distinguish vitiligo from other hypopigmentary disorders. The presence of islands of pigment, erythema, or telangiectasias in the center of the lesion suggests repigmentation. At the periphery of the lesion, unstable vitiligo often shows a diffuse border, trichrome pattern, micro-Koebner/comet tail phenomenon, satellite lesions, or a tapioca sago pattern. In contrast, stable lesions more frequently present with clear borders and trichromes. Pigmented lesions commonly exhibit sharp borders and marginal or perilesional hyperpigmentation.
Can IBOOLO Dermoscopy Detect Vitiligo?
Both the IBOOLO DE-3100 Pro and DE-4100 Pro are equipped with four 365nm UV lights, so they both have UV light functionality. Moreover, compared to Wood's lamp, the advantage of the dermatoscope lies in its relatively higher magnification, which provides clearer enlargement of skin lesions. For instance, the magnification of the two IBOOLO Wood's lamps is 4.5X, while the IBOOLO dermatoscope achieves a magnification of 10X.
However, if you only need to use the UV light function to observe skin lesions, Wood's lamp is the best choice. If you also need to observe other types of light, such as polarized or non-polarized light, then a dermatoscope would be a good option.
How Can Dermatoscopy Help Avoid Misdiagnosis?
Dermatoscopy can differentiate vitiligo from other hypopigmentary disorders such as pityriasis alba, pityriasis versicolor, idiopathic guttate hypomelanosis, and achromic nevi. For example:
Pityriasis Alba: Exhibits white structureless areas without a glow, a faint pigment network, and superficial white scales.
Pityriasis Versicolor: Also shows white structureless areas without a glow, with prominent scales in the skin lines that separate into lines when the lesion is stretched.
Idiopathic Guttate Hypomelanosis: While it shows a similar glow to vitiligo, the white areas are clearly demarcated from normal skin and have amoeboid, petaloid, feathery, and nebuloid morphological variants.
Achromic Nevi: Characterized by white structureless areas with a faint pigment network in the background. The glow is absent due to the presence of the pigment network, and white areas may extend peripherally.
What is the Role of Wood's Lamp in Clinical Management?
Wood's lamp is highly valuable for early detection of vitiligo, especially in areas where lesions are not easily visible to the naked eye. It can also be used to monitor the effectiveness of treatments like phototherapy and drug therapy. Additionally, Wood's lamp can guide biopsy or pigment transplantation procedures by helping to determine the optimal site for these interventions.