DermNet provides Google Translate, a free machine translation service. Note that this may not provide an exact translation in all languages


Teledermatology for suspected skin cancers

Basic dermatoscopy

Created 2017.

There are many systems and algorithms.  

  • Conventional pattern analysis with morphological terminology has been shown to be very accurate. But it’s complicated, and takes a long time to learn. 
  • Modified pattern analysis described by Harald Kittler uses descriptive terminology and is easy to learn, but sometimes clumsy.
  • Compare "yellow dot surrounded by skin-coloured circle surrounded by unfocussed curved thick red lines and sometimes angulated brown lines" (descriptive method) with "strawberry pattern" (morphological method).
  • People who have learned both methods tend to use a combination of morphological and descriptive terms.

Modified pattern recognition


  • Skin lesions are made up of basic dermatoscopic elements.
  • The elements group together to form patterns.
  • These terms describe pigment/melanin and blood/blood vessels.

The 3 most basic elements are:

  • Lines
  • Clods
  • Structureless zones (no lines or clods)

Other elements are:

  • Dots (smaller than clods)
  • Circles (joined-up lines)
  • Pseudopods (clod on the end of a line)

Colours in dermatoscopy:

  • Melanin: black, dark brown, light brown/tan, grey, blue from superficial epidermis to deep dermis
  • Keratin: white, yellow
  • Blood: reddish black, red, purple, blue

Arrangements of lines include:

  • Network / reticular pattern
  • Lattice pattern
  • Radial pattern
  • Parallel pattern
  • Curved parallel lines

Structures can be:

  • Peripheral
  • Central
  • Scattered
  • Grouped

A benign skin lesion has symmetrical structures and patterns

  • Its shape may or may not be symmetrical
  • It is made up of elements forming 1, 2 or 3 patterns
  • It usually has only 1 or 2 colours

A malignant skin lesion rarely has symmetrical structures or patterns

  • It includes ≥ 2 elements / patterns, usually ≥ 3
  • These are distributed irregularly
  • Often there are ≥ 5 colours
  • Destructive lesions can lose lines and clods
  • Grey and white structures often  represent regression and/or scarring

See smartphone apps to check your skin.
[Sponsored content]


Related information

On DermNet NZ

Sign up to the newsletter