| What is dermatoscopy? | • Dermoscopy (dermatoscopy), is an essential tool for dermatologists, plastic surgeons, general practitioners attempting early diagnosis of melanoma
• Using dermoscopy to evaluate pigmented lesions, the abnormal structural features of melanoma can be identified, borderline lesions may be closely observed and benign lesions can be confidently diagnosed without the need for biopsy
• Dermoscopy is also increasingly useful in diagnosis of non-pigmented skin lesions and inflammatory dermatoses |
| How is mechanism of action of dermatoscopy? | Dermoscopy requirements include a high quality lens for 10 to 14-times magnification and a lighting system
This enables visualization of subsurface structures and patterns
Hand-held devices are usually lightweight and battery-powered
Fluid immersion and polarized systems are available |
| How is effectiveness of dermatoscopy? | • It is estimated that dermoscopy can detect 92% of melanomas immediately because of typical features
• The remaining 8% do not have identifying features and are diagnosed because of change in an atypical lesion
• Structural change can be detected in superficial melanomas within 3 to 6 months |
| How is whole body photography? | • Surveillance of patients at risk for melanomas is greatly aided by the use of high quality images of the entire integument. It is particularly useful for those with atypical nevi or many moles
• New lesions can be identified by careful comparison with older images. Lesions that are of concern can be kept under review, reducing unnecessary excisions if they are stable
• Significant change in size or shape of individual lesions should be examined by dermoscopy and may prompt biopsy
By dermoscopy, the pigmentation of the lesion is
evaluated in terms of color(s):
black, dark brown, tan, grey, steel blue, purple, white, yellow and red |
| What are the 3 checkpoints of dermatoscopy? | • The dermoscopy 3-point checklist for early detection of skin cancer is fairly easy to learn and has a high sensitivity for melanoma. The 3-point checklist has been designed to allow non-experts not to miss detection of melanomas
• Asymmetry: asymmetry of color and structure in one or two perpendicular axes
• Atypical network: pigment network with irregular holes and thick lines
• Blue-white structures: any type of blue and/or white color, i.e. combination of blue-white veil and regression structures |
| What are types of lesions according to finding on dermatoscopy? | Benign: Symmetrical, uniform network, no blue-white structures , Mild asymmetry of structure, no network, no blue-white structures
Melanoma: Marked asymmetry of structure, network is ok, subtle greyish blue structure, Mild asymmetry of structure, broad dark grey network which has blue-grey veil
Blue-white structures can refer to any type of blue Blue-white structures can refer to any type of and/or white |
| How does dysplastic nevus appear on dermatoscopy? | Atypical naevus
Dysplastic naevus is a histological description of a particular kind of melanocytic naevus
•Size > 5 mm diameter
•Ill-defined or blurred borders
•Irregular margin resulting in an unusual shape
•Varying shades of colour (mostly pink, tan, brown, black)
•Flat and bumpy components |
| How is lentigo maligna on dermatoscopy? | Type of melanoma in situ
Precursor to lentigo malignant melanoma
Lentigo maligna is also known as Hutchinson melanotic freckle |
